This section is designed to help you, the Customer understand Off-road buggies & what is involved.

• Q/ Which buggy design is right for me?
  A/
  There are a few factors involved with choosing a buggy for yourself.
  
  1/ Are you going to make the buggy yourself from scratch?
  2/ What is my $$$ budget?
  3/ Where am I going to drive the buggy?
  4/ What type of performance am I looking for?
  5/ What skills do you have?
  
  If your welding & fabrication skills are lacking, but your mechanical skills are OK you could either look at convincing a friend to help you weld the chassis or purchase a complete chassis or kitset.
  
  If you are a complete novice & you want to make the buggy yourself from the ground up, the best bet is to pick a simple buggy as a first project.
  This way you are not spending too much money & you get to learn how things work.
  There is no point taking on too big a project & never finishing it.
  
  If you have money but no time, purchasing a rolling kitset will save you a lot of time & ensure a good quality buggy.
  
  Remember, performance costs money. The more work you can perform yourself the cheaper your project will be.
   
• Q/ Can I purchase plans for the buggies shown on this web site?
  A/
  Yes, you can purchase the plans for each buggy listed in the “Buggies Menu”.
  All plans can be purchased online through our secure ordering facility with a credit card.
   
• Q/ What skills do I require to build my own buggy?
  A/
  If you are going to build the whole buggy yourself to the plans & make most of your own parts you require general engineering skills.
  
  That means you need to know how to cut material to specified sizes, drill holes to the drawings & set up & fabricate the chassis & parts.
  
  To stick the whole project together you are also going to need to know how to weld.
  
  General mechanical knowledge is also required in setting up the motor & associated parts.
  Most parts are available from The Edge Products, so if you get stuck, you can purchase the required part.
   
• Q/ Can the Edge send me the parts I need if I get stuck?
  A/
  Yes, The Edge freight parts all over the world every second day, (Mondays, Wednesdays & Fridays).
  Most small parts, (including suspension arms, shock absorbers etc) are sent through the Postal system via Air mail.
  
  Parts can be ordered on this web site through our secure ordering system.
  
  Larger items like chassis frames & complete kitsets have to go sea freight if you are outside of Australia.
  
   
• Q/ How long does it take for plans & parts to get to me?
  A/
  All plans are sent Air Mail, this takes around 5-10 days to most destinations around the world.
  If parts are being sent via Air Mail it takes around 7 to 10 days.
  Sea freight of large items can be 12-40 days depending on your location.
  IE: New Zealand is 10 days, United Kingdom 26 days, USA 35 days.
   
• Q/ Are the Edge kitsets ready to drive?
  A/
  No, all of The Edge kitsets are supplied in un-painted form.
  Some of the smaller buggies come with the motor & transmission & all these kits require is painting & assembly.
  
  Kitsets sush as the Sidewinder, Piranha & Hypersprint require you, the builder to purchase your own secondhand motorcycle motor.
  
  You then have to install & make your own motor mounts, set the motor up with radiator, gear change, wiring & exhausts.
  The final phase is to paint & assemble the buggy ready to drive.
   
• Q/ What tools or equipment do I need to construct my own buggy?
  A/
  If you are going to make most of the parts yourself to the plans you will require most of the following tools.
  • Welder, either a Mig or Arc welder.
  • Grinder
  • Drill or drill press
  • General hand tools like spanners, screwdrivers, hammer, hacksaw, drill bits etc.
  • Bench vice
  • A flat bench to work from, can be made from sheets of chipboard or plywood. Used as a flat surface to layout & fabricate the chassis & major parts.
   
• Q/ Can I jump an Edge buggy?
  A/
  Yes you can jump an Edge buggy.
  But the higher you jump the harder the landing will be.
  Also the higher you jump the more likely you are to inflict serious damage on the buggy & yourself!
  
  A Sidewinder will not jump as well as a Piranha or Hypersprint.
  Because the Sidewinder has a one piece swing arm rear, both wheels travel up & down together.
  That means the Sidewinder will see more stress in the rear axle if landing on one rear wheel.
  Landing on one rear wheel is trying to twist the rear suspension.
  
  A buggy with independent rear suspension like the Piranha or Hypersprint can absorb these impacts with greater ease as each wheel can absorb the impact independently.
  
  Watch the Crusties movies & you will see their biggest jumps always have a decent down ramp for a landing.
  
  On the sand dunes this is generally the downside of a large dune face.
  
  The reason being is that you contact the down ramp first with your rear wheels, your still going downhill so the suspension compresses gradually & the machine will slowly flatten until the front makes contact.
  
  This is the smart way to jump.
  
  The dumb way?..... Check out Seth in the Crusties video’s, he lands on the flat & snaps the bike in two & wipes himself out.
  
  That’s even worse in a buggy as all of the buggies weight slams into the ground, bang, all at once the suspension compresses, can bottom out & suddenly you have broken a suspension arm, mounting point or shock & your teeth are jammed into the top of your skull.
  
  Anybody who really expects to do this & get away with it has either invested a couple of grand on each shock, (minimum) or is related to Seth.
  
  So.....there’s a right way & a wrong way.
  Anyone who rides Super cross or Moto X will tell you that you have to get that down ramp just right.
  In a buggy times that advice by 10, its even more important because your packing allot more weight, & when your airborne, man your committed, you can't jump out!!.
   
• Q/ What does CAD mean?, I see The Edge advertise the plans are CAD drawn, what does this mean & how does it help me?
  A/
  CAD means Computer Aided design.
  
  The Edge have employed this system of buggy design for many years & it has helped greatly in designing an accurate & precise buggy.
  
  The System we use is called “Solidworks” which is one of the engineering industries premier design programs.
  
  A very powerful computer workstation is employed to help “Solidworks” generate the complex parts in quick time.
  
  All parts are fully generated on the computer in 3D, so the part is 100% accurate in size & shape & actually looks “real” on the screen.
  
  Parts are then put together on the computer into an assembly, an example of an assembly can be a brake caliper which is made out of many parts such as pistons, seals, alloy body, mounting bracket etc.
  
  All of the parts that make up this caliper are individually drawn, during the assembly of the parts that make up the finished caliper it becomes obvious if the parts fit together or not.
  This means faults are ironed out of design long before a drawing ever reaches the factory floor.
  
  This caliper may then become part of a “sub-assembly” which may include items such as wheel hub, bearings, stub axles & disc rotors.
  
  The chassis is also created as parts, each tube is a part & can be assembled & dismantled on the computer screen.
  
  The whole buggy then becomes one big assembly, which is made up of parts & sub-assemblies.
  
  Obviously the designer needs to know what he or she is doing to create a new design on the computer.
  The Edge Products have been manufacturing Offroad Buggies since 1989 so there is a great deal of knowledge & skill to draw on to create that new innovative Buggy.
  
  What this all means to you, the buggy builder is that the plans generated by this sophisticated CAD program are extremely detailed, accurate & show many 3D views.
  This removes a lot of the guess work, parts are shown in 3D views which are real to the eye, this makes the job at hand easier to visualize.
  
  Detailed plans make your job much easier & gives you the confidence to make the buggy accurately without the guesswork.
   
• Q/ Can I make my chassis out of Aluminium?
  A/
  All Edge chassis & parts are made out of Mild Steel for ease of manufacture & to keep the costs reasonably cheap.
  
  Yes it’s possible to make a buggy chassis from Aluminium.
  
  But Aluminium has characteristics that make it much more difficult to work with compared to mild Steel.
  
  Welding a heat treated alloy anneals the heat affected area.
  So the strength of the welded area becomes the same as that material in annealed condition.
  This means the welded area becomes softer than the rest of the bar work.
  
  Unless you heat treat the whole chassis it’s going to be very weak.
  
  Without heat treating the chassis welds & the surrounding area will be soft & prone to failure.
  To beef up the structure to combat this lack of strength will add weight.
  
  There are very few Aluminium alloys that are suitable for the welding task.
  The high tensile 7000 series alloys are not suited to welding.
  This is the reason that many of the early aluminium tubbed race cars were riveted.
  By riveting sheet aluminium you can then use the tensile grades of this alloy.
  Only the 6000 series Aluminiums are weldable, 6061 being the most suitable.
  Ultimate tensile strength around 45ksi, but falls off to 24ksi when welded, heat treating will bring it back up to 45ksi.
  
  As a guide aluminium would have to be 1.44 the thickness of steel to achieve the same bending stiffness.
  But the aluminium would only be .48 of the weight even though its thicker.
  So there is a good weight advantage.
  
  When welding aluminium allot of effort has to be put into creating a stiffer joint.
  Gusseting corners, extra bracing to create more stiffness.
  Aluminium does not tolerate flexing at weld joints, it cracks.
  This is because Aluminium fatigues very quickly.
  You can flex steel all day long & it will withstand this stress.
  Aluminium will fatigue & fail with only 1/3rd the amount of cycles compared to steel.
  So there needs to be extra wall thickness in the tube as well as care not to have undercuts at the weld.
  
  Corrosion is another factor.
  When an object is pushed close to its mechanical limit it only takes the slightest amount of corrosion to bring it to the point of failure.
  
  Aluminium needs to be protected from the elements as it corrodes quickly.
  
  When all said & done you need to be skilled in the art of Aluminium fabrication.
  You need to understand its advantages & disadvantages to be successful in achieving a good strong structure.
   
• Q/ What type of paint do I use on my buggy chassis & parts?
  A/
  By far the best surface finish for a buggy chassis is powder coating.
  
  We have had hundreds of buggies powder coated at The Edge & if it’s applied correctly you will not find a more durable finish.
  
  I have seen buggies painted in two pack & although the finish was excellent the durability did not match powder coat.
  Two pack tends to be more brittle & chips easier from corners.
  
  If a chassis is sandblasted, pre-heated & powder coated it will have a very tough, chip resistant, (within reason) good finish.
  
  To increase resistance to corrosion there are things you can do before powder coating such as zinc plating, (small parts) or metal etching primers.
  
  I have never found a need for these pre treatments if the quality of the application is good.
  
  Sandblasting is an absolute must & I also feel the same about pre-heating the chassis before the powder is applied.
  
  Sandblasting takes off all scale, paint & rust & brings the chassis back to an even fine grained surface.
  
  The grainy surface helps the powder coat resin "key" onto the metal surface.
  
  The powder coat must be applied soon after sandblasting so rust does not get a chance to form on the metal surface.
  
  It’s best to use a powder coating company that has both of these facilities in house.
  
  Stress greatly that the sandblasted chassis must be blown down in every nook & cranny before powder coating, with an air gun that has a water trap!!
  
  The idea behind pre-heating the chassis is I have found that the heavier plate material obviously needs more time to get to temperature than the thinner tube material.
  
  If pre-heating is not done the powder coat bond on the heavier material tends to be not as good as the thinner material.
  
  Plug up any threaded holes with old bolts.
  
  Male threads can be covered with rubber tube such as old fuel; oil & radiator hose as long as the hose is a snug fit & clean.
  Don't use plastic as it will melt at oven temperatures & make a mess.
   
• Q/ What are the advantages of Double “A” arm suspension compared to single arm?
  A/
  The Double A arm rear suspension will be a little more expensive as there are more components.
  
  One of the advantages in a double A arm is it allows the wheels to droop, (sag downwards) when the buggy is unloaded.
  
  This means in situations of hard cornering the inside wheel will stay put on the ground when the vehicle has some body roll.
  
  The amount of droop depends on the design, but the idea is to keep the wheel either upright or slightly into negative camber.
  
  You never want a situation of positive camber as the wheel could tuck under.
  
  Droop also keeps the wheels under traction on bumps & hollows.
  
  Double A arm also has the advantage to be able to design the suspension to control the amount of negative camber during suspension movement.
  
  Negative camber is good for a buggy, it aids in stability.
  
  Single arm suspension moves through an arc & progressively goes further into negative camber.
  Progressive camber change is also good, but with a single arm there is going to be a limit to suspension travel as the wheel will start to become horizontal.
  
  Double A can be designed to have the amount of camber you want for the job at hand.
  It’s also a stronger setup, the pivot points are spread over a larger area.
  
  This aids in absorbing torque reactions from the drive shafts & spreading suspension forces into different areas of the chassis structure.
   
• Q/ What’s negative camber & how does it help my buggy?
  A/
  Negative camber is the wheel leaning inwards at the top.
  
  That means if you viewed a buggy from above that has negative camber, the top of the wheels would be closer together than where the tyre touches the ground.
  
  The reason behind Negative Camber is to create more stability in corners.
  
  If you throw your buggy into a corner at a decent speed the suspension on the outside of the buggy will compress.
  That means, turning into a left hand corner the right side of the chassis will become lower to the ground.
  This is because weight is being thrown outwards by centrifugal force.
  This is called body roll.
  The chassis, (body) is throwing weight onto the outside suspension & compressing the shocks & springs.
  
  In a buggy with a suspension design that allowed the wheels to travel up & down parallel to the chassis it would mean the bottom of the wheel would tuck under during body roll.
  
  This could cause the tyre to peal from the rim or the rim itself to buckle under load.
  The result could be the buggy rolling over & damaged wheels.
  
  If the suspension was designed to progressively arc the wheels into Negative camber the outside wheel in a corner would remain relatively upright in relation to the ground.
  This would increase the traction available with less tyre & rim distortion.
  
  Another practical advantage of Negative camber is a buggy landing from a jump.
  It is hard to control a buggies attitude when its airborne, often one end of the buggy can drop or one corner can drop in flight.
  This means the buggy will land at a very crooked angle instead of landing flat on all four wheels.
  If you imagine the front right wheel landing first as the buggy contacts the ground the buggy is exerting all of its weight & forward motion onto one wheel.
  
  Again, if the suspension is designed to travel up & down in its motion parallel to the chassis this wheel can tuck under.
  This situation will certainly cause a great deal of damage to the wheel & suspension components & could result in the buggy rolling over.
  
  At best the buggy may survive the landing but great stress could have been induced into the wheel & suspension causing it to later fail.
  
  If in this situation the suspension was designed to again travel through its motion & progressively arc inwards into Negative Camber the wheel will remain fairly upright in relation to the ground.
  With this feature the buggy is more likely to keep moving forward & safely land onto all four wheels.
  
  How much negative camber depends on the total suspension travel available.
  A good guide is 1 degree per 50mm of wheel travel.
   
• Q/ Can I use a brake bias valve in my buggy & use a hand brake to get the tail sideways in corners?
  A/
  Brake bias was designed for circuits, a track where you know every corner like the back of your hand.
  
  So you know that corner “A” needs a number “2” setting on the bias lever & corner “D” needs a number “4” setting on the bias lever.
  
  In that situation it works well.
  
  If you have never been around a certain corner, you don't know how tight its going to be or the surface conditions, how then do you know what bias setting to choose?.
  
  You can't.
  
  Independent front & rear brakes, just like a motor cycle gives you infinite control, at a micro seconds notice.
  
  I have thrown buggies into corners at some hell speeds with my left foot on both front & rear brake pedals together, washing off the speed very nicely, then the front starts to lock & I instantly rock my foot to the left, I am now on the rear only & using the rear to step out the tail.
  
  During this whole process my right foot is on the gas feathering the throttle & controlling speed & the attitude of the buggy in a controlled drift.
  
  Gearshift & clutch are both on one lever & require only one hand to operate; I have two hands free because I don't need a hand brake!
  
  If in this situation if my front & rear brakes were interconnected I would have had no choice but to totally get off the brakes because the front was locking up, keeping on the brakes I would have no steering at all & under steer rapidly towards the outside of the corner.
  
  I would have then been traveling too fast going into the corner with no way to wash off more speed, I would have also had to grab for that handbrake to try & get the rear to step out & point me into the corner.
  
  It would have been a mess & I would be in the trees.
  
  The reason why the rally cars don't run twin brake pedals is that CAMS rules do not allow it.
  The rules are based on cars & that they must have a duel braking circuit on one pedal.
  
  We overcame this on the Ballistic buggy.
  We fitted our twin brake pedals but with an extra feature.
  When the front pedal is applied it also applies the rear.
  But when the rear pedal is applied it only operates the rear, not the front.
  
  This way we have more controllable brakes but also comply to the rule book.
   
• Q/ What type of disc brake rotors do I use on my buggy?
  A/
  Car discs are cast iron, bike discs are usually steel or stainless steel.
  
  Car discs are totally different, you skim the surface to get rid of the hard skin that builds up & to make the disc flat again.
  
  Cast iron car discs are also very heavy which would add excessive weight to a motorcycle engine powered buggy.
  
  The Edge buggies run discs like a motorcycle.
  
  Making a disc out of steel means that the steel has that "Hot worked" scale on the surface.
  This scale is real hard, so hard that brake pads will not penertrate this scale & the pads tend to slide on the hard surface without getting a good bite.
  
  So it feels like fade is happening, but it isn't.
  Its that the pad cannot get a good bite & slow the disc down.
  After all, brakes are about increasing the friction, not decreasing it.
  
  If you bead blast the disc it takes off that layer of scale & brings the disc back to bare steel, now the pads will grip the surface instead of just skidding over that hard layer.
  
  Instead of bead blasting you can also have the discs zinc plated.
  
  The first process in zinc plating is to acid dip the part, this removes the scale.
  
  Then the disc is zinc plated which puts a fine layer of zinc on the surface, it actually etches into the surface, not sit on the top like Chrome plating.
  
  There is no layer to flake off.
  Same as nuts & bolts, they are also zinc plated.
  The brake pad will quickly wear off the zinc in the pad area, back to bare steel, but leave the rest of the disc in a corrosive free state.
  
  Its rare to see a buggy cook its brakes, the vehicle is simply not heavy enough to do that & offroad use does not put as many demands on brakes as a street vehicle would.
  
  We sell a new twin piston caliper which works real well, (CAL032).
  The first time I tested it the rotor turned blue & the brakes faded in about 2 minutes.
  
  That was the brake pads.
  
  So I changed the pads to English made EBC brand that are Kevlar based.
  
  Wow what a difference, no excessive heat build up & you could lock the back wheels with just a tap of the pedal.
  
  No fade either as there was less heat build up.
  
  So I went straight ahead & ordered a big batch of EBC pads.
  
  You will see all aftermarket discs for Moto X bikes are also zinc plated steel.
   
• Q/ Why does the Hypersprint have pushrod suspension?
  A/
  Pushrod suspension was first developed for Formula one race cars.
  
  On a blacktrack race car like a Formula one car they have very little movement in the suspension & shocks.
  Most of their design logic is to improve aerodynamics & a small amount of un-sprung weight reduction.
  
  For offroad use, (as far as I am aware The Edge is the only company to explore pushrod on an offroader) we are after different things.
  
  * Reduced shock weight, we can use a shorter stiffer shock & use the lever advantage of the bellcrank to obtain suspension travel.
  * Reduced shock stroke, this means less heat generated within the shock, thus less fade.
  * Shocks mounted lengthways in the chassis. Modeling & FEA has indicated at least 40% of the suspension energy is transmitted lengthways into the chassis; this means the chassis is prone to 40% less twisting force.
  Since 90% of all force & energy on the chassis comes from the wheels hitting large bumps this then reduces chassis twist greatly.
  * Rising rate can be built into the design.
  
  The pushrods & bellcranks handle the load fine.
  The Hypersprints rear springs are up around the 480 lb mark.
  
  Its my opinion only, but I think for offroad use pushrod is the future.
  If you have ever picked up an offroad racing shock, you will see what I mean in regards to weight.
  That weight is not good for the buggies overall weight, & also terrible for un-sprung weight & suspension performance.
  Also those real long shocks suffer badly from shock fade due to the huge stroke.
   
• Q/ Do Edge buggies have a differential?
  A/
  No, none of The Edge buggies have a differential.
  
  As far as a buggy is concerned a diff has some good & bad points.
  
  Good points are that its easier to steer into corners at low speeds & you can install cutting brakes to get you around those really tight corners.
  
  (Cutting brakes are a system of one disc brake per rear wheel operated by individual levers, one lever for each rear wheel)
  
  Bad points with a diff is that traction is very compromised.
  
  As with most diff’s, all the power ends up going to the wheel that has already broken traction.
  
  That means you will spend a lot of time trying to dig your buggy out of the sand when its bogged up to its axles.
  
  Its possible to correct the poor traction a diff creates with cutting brakes but which wheel is spinning?, you can't see what’s happening behind you & even if you could, trying to react that quickly when your doing 120-140 kph through a corner is near impossible.
   
• Q/ How do I mount the motor in my Buggy?
  A/
  Here are a couple of examples in fitting a motor to your buggy.
  
  Fitting a Yamaha TRX/TDM into a Piranha or Hypersprint.
  
  The Yamaha TRX/TDM850 is an easy fit in the Piranha as it’s a very compact motor.
  Main consideration is lining up the chain.
  First drop the motor into an approximate position, wrap a chain around the two sprockets so you can see if the chain will foul on anything.
  This will give you an indication as to go up or down or forward & back with the motor for ideal position.
  Make sure the word "YAMAHA" on the side cover is horizontal.
  Pack the motor up with scrap steel or timber wedges to the ideal position.
  Take the chain off & use a straight edge across the motor & rear axle sprocket to line up the sprockets.
  Keep in mind the two sprockets may be slightly different thicknesses.
  You need to square the motor to the frame, you may be able to work off the machined face under the motors sprocket cover.
  Pick the most simple mount once the motor is solid & in position & tack weld that in first.
  Then go around the motor & make the other mounts.
  You may have to make some of the mounts removable, keeping in mind the best direction to get the motor in & out of the chassis.
  To make a removable mount you can manufacture a matching pair of rectangular flange plates from flat bar.
  One is drilled & tapped & welded to the chassis, the other has matching clearance holes & is part of your removable mount.
  Plates of 1" x 1/4", (25x6mm) flat bar around 2", (50mm) long, with a hole in each end where they will bolt together.
  
  Fitting a Kawasaki KLX650 into a Sidewinder
  
  The easiest way is to sit the motor on the chassis in approx the right position.
  
  The main thing you are trying to achieve with a Sidewinder is lining up the centre of the engines output sprocket with the centre of the rear swing arm pivot point.
  
  Take note of the difference in height between the motor output sprocket centre & the suspension arm pivot centre.
  
  Let’s say as an example its 40mm.
  
  Then look at the area of the chassis that is stopping the motor going downwards by 40-45mm.
  
  Keep in mind the motor has to drop 40mm & what area of the motor will foul on the chassis once it’s dropped down 40mm.
  
  Isolate this area of the chassis & cut it out.
  
  Now you can position the motor exactly where you want it.
  
  Pack the motor into the correct position & take time to get the motor straight & square in the chassis, make sure it’s not going to move.
  
  Now pick the mount that’s going to be easiest to make.
  You can't make any rear mounts because you have cut out that section of the chassis so have a look at the lower front of the motor’s crankcase.
  
  If you fabricate the mount & tack weld it in place so its reasonably strong, now you don't have to be quiet as careful with working around the motor, its now part mounted & unlikely to move around.
  
  Pick the second mount to make.
  The KLX has a mount on the front & back of the cylinder, the rear mount is closer to the chassis top frame so this is a good second mount to make.
  It may be a good idea to make this mount a bolt on part so it’s easier to get the motor in & out.
  
  Once you have the second mount secure & well tacked in you can remove all the packing pieces that were propping up the motor.
  
  Now you can look at repairing the section of the chassis you cut out & re-box it around the motor.
  Once this is done you can make the lower rear mount & that’s it.
  
  Keep in mind at all times that you will need to be able to un-bolt the motor & it should easily lift out.
   
• Q/ What type of motor is best for the Sidewinder?
  A/
  The Sidewinder design uses a motorcycle motor mounted along side the driver, generally on the right side of the chassis.
  
  The reason for the side mounted design is to have the motors output sprocket line up with the rear suspension swing arm pivot point.
  This means that when the suspension arm arcs up & down the chain will remain a constant tension.
  
  A side mounted motor will un-balance a buggy if the motor is either too heavy or the motor is positioned too far away from the chassis centre line.
  
  With this in mind a single cylinder motor is the lightest design.
  
  So what type of single cylinder motor suits the Sidewinder best?
  
  Four stroke single cylinder trail bike motors are the most user friendly in terms of good power to weight ratio & lots of low end torque.
  Most modern trail bike motors are also fitted with electric start, this is a big bonus to the driver as once you are strapped into your buggy the last thing you want to do is un-buckle & climb out to kick the motor over again.
  
  Two stroke Moto X bike motors are very powerful & light weight.
  This type of motor in 500cc form produces a very powerful buggy, but the negative side is the intense vibration, lack of electric start & the temperamental nature of the two stroke motor.
  
  The best models of motorcycle engine are as follows:
  This is a sample of motors that are available in the secondhand market.
  
  KLX650 Kawasaki
  KLR650 Kawasaki
  KLR600 Kawasaki
  DR650 Suzuki
  DR600 Suzuki
  XT600 Yamaha
  XT500 Yamaha
  SR600 Yamaha
  SRX660 Yamaha
  660 Yamaha Raptor
  XL600 Honda
  XR600 Honda
  XR650 Honda
  NX650 Honda
  FT500 Honda
   
• Q/ What type of motors are best for the Piranha or Hypersprint?
  A/
  The Piranha / Hypersprint designs use a motorcycle motor mounted behind the driver, commonly termed as mid mounted.
  
  The rear central mounting of the motor creates a well balanced buggy with very good handling characteristics.
  
  The best suited motors being a motorcycle chain drive type, water cooled with anything from one to four cylinders.
  A motor with electric start is important as access to a kick start is limited.
  
  Air cooled motors can also be used with care taken to divert air to the motors head & cylinders with the aid of scoops as well as a suitable oil cooler installed.
  
  Motorcycle motors in the range of 500cc up to 1100cc are suitable.
  The following is a general list of available motors, most coming from road bikes.
  There are many more suitable models not included here.
  
  VTR1000 Honda
  CBR900 Honda
  CBR1000 Honda
  NX650 Honda
  XR650 Honda
  GSX750 Suzuki
  GSX1100 Suzuki
  TL1000 Suzuki
  Suzuki 1200 Bandit
  FZ750 Yamaha
  FZ1000 Yamaha
  TRX850 Yamaha
  TDM850 Yamaha
  RSV1000 Aprilia
  ZXR750 Kawasaki
  ZZR1100 Kawasaki
  KLX650 Kawasaki
  KLR650 Kawasaki
   
• Q/ I see a lot of talk about using motors with lots of low end torque, why is this ?
  A/
  Torque is a matter of leverage, acceleration of mass & the motors resistance to the mass slowing down.
  For example, a motor with a long stroke has more leverage because of the crankshafts offset. The distance from the crank center to the big end is the amount of leverage. The bigger this offset, (the stroke) the more torque a motor will have.
  This is because when you increase the offset it also has to be counter balanced to make sure the motor is balanced & runs smooth. This also means that a larger stroke offset will have increased mass, (weight) compared with a short stroke motor.
  This increased mass rotating at a larger diameter than a short stroke crank has more inertia, the mass at a larger diameter has more centrifugal force & inertia which means its hard to slow it down. Now combine this with a heavy flywheel & you end up with a crankshaft assembly that is hard to stop.
  This would be the combined mass of the crank, flywheel, con rods & pistons. But, because this rotating assembly is heavy, it also takes longer to accelerate. That is why a short stroke motor, ( large bore & short stroke) picks up its revs very quickly.
  But a short stroke motor is also very easy to slow down, it does not have the leverage of the long stroke crank & the weight in the rotating assembly.
  Now the higher you can rev a motor the more fuel you will consume over that given time. This equals more power.
  So a short stroke revy motor will consume more fuel at high revs & produce more power than a motor of the same capacity with a very long stroke & small pistons.
  Look at an F1 car, its 3 litres in capacity, very short stroke & revs in excess of 18,000 rpm. BUT, some drivers have problems on race starts because the motors have very little low rpm torque.
  This means they have to rev the motor to increase power & torque to increase the rotating mass to a higher rpm, thus more leverage to get the car moving.
  You will find that super short stroke revy motors have a very narrow usable power band. That is, the motor is really only useable within a certain rev range. Like a two-stroke motor that has a narrow power band, outside of this rev range it wants to stall.
  This brings us to the relationship between horsepower & torque.
  Horsepower is a product of RPM & torque combined. The higher the RPM the higher the inertia of the rotating mass, so the higher the RPM the harder it is to stop or slow down the motor.
  So look at the two types of motor. A long stroke motor of High Mass that only revs to a low rpm can have high torque at low RPM.
  A short stroke motor that revs to high RPM can have high torque because the motor is consuming a large amount of fuel at the high revs & producing power.
  So we can see that a short stroke revy motor generally will not have any torque at low rpm, it does not have the mass or leverage to keep it going.
  
  A long stoke motor will take longer to build up its revs & it will not rev as high but it will have more torque at low revs because the mass is greater & harder to slow down.
  As far as motorcycle motors are concerned look at a KLR600 Kawasaki, it’s a single cylinder motor with a big bore & a long stroke.
  Compare this to a Kawasaki ZZR600, a four cylinder motor of small bores & short stroke. The KLR600 will take longer to pick up its revs & will only rev to around 7,000 rpm. The ZZR600 will pick up its revs quickly & rev out to an easy 12,000-RPM. The KLR600 is good for about 50 hp, the ZZR600 around 100hp.
  But the KLR600 has a broad spread of torque from low rpm right up to its 7,000 rpm. You do not have to keep working up & down the gearbox to keep the vehicle moving.
  The ZZR600 has high power & torque, but only when its revving high & consuming all of that fuel.
  If the revs drop, so does the torque. The KLR600 you can dump the clutch at an idle, the motors rotating mass is keeping the momentum moving, so it’s hard to stall.
  The ZZR600 has to be revved to take off, it has little rotating mass so you need to increase the RPM to increase the torque.
  Now both motors are great, but for different uses.
  The ZZR600 has twice the power, but to use that power it has to be revved. Offroad driving is different to on road driving.
  On the street traction is easy to come by, so the ZZR600 can be used right across its rev range.
  But take that motor off road into a boggy situation & the load on the motor increases. To take off you need the torque to get the weight of the vehicle moving, so you give the ZZR a good rev so it won't stall, but that makes the rear wheels spin faster & you start digging a trench.
  If you have very wide tyres & lots of floatation you may get out of that trench & get moving.
  The KLR will take off at low rpm without spinning the wheels, you are getting positive traction & you start to accelerate, you are moving through the boggy sand fast because the torque is hooking up & the lack of rpm is preventing the wheels from spinning.
  As soon as you get some speed up you can roll on more revs as you have some momentum now. The ZZR is still stuck in its trench, it can't climb out of it because as soon as you back off the revs to stop the wheels spinning the motor wants to stall & you slow down. The ZZR600 would be more usable with lower gearing, this will increase the torque as the lower gearing is increasing the leverage. But its power delivery is still at a high rpm & the power band is narrow, so you have to work the gears up & down hard to keep it in this power range, you are thrashing the motor hard.
  
  What is great for the street is not always great for offroad, two totally different situations that require different solutions.
  
  Horsepower = TORQUE x RPM divided by 5252
  TORQUE = Horsepower x 5252 divided by RPM
   
• Q/ Is the operating temperature of my motor a real problem?
  A/
  Keeping a motorcycle motor at the correct operating temperature is important to the life of the engine.
  
  If the motor runs too hot, excessive RPM is what will kill the motor as temperature will soar higher & the oil will loose its lubrication properties.
  
  Combined with thermal expansion of pistons, rings etc.
  
  In this situation the edges of the piston crown can start to melt, combined with any carbon deposits glowing; this leads to a pre-ignition situation.
  
  Pre-ignition is then a concern as the temperature ignites the air/fuel mix before the piston reaches top dead centre.
  Pre-ignition tries to turn the motor backwards but the combined mass of the moving parts keeps the motor moving in the correct direction.
  
  So there becomes an opposing force which stresses the internals.
  Pre-ignition, (detonation) will kill a motor quickly.
  
  This is often a bigger concern for two stroke motors than four strokes.
  
  A motor rising in temperature too quickly can be for a few reasons:
  
  Low oil level resulting in poor lubrication & excessive friction.
  
  Poor oil quality or oil that’s very old.
  Lack of cooling to the motor if its air cooled or in the case of a water cooled motor, the radiator may be too small or lack a suitable size fan.
  
  Blocked radiator creating a lack of coolant flow to cool the engine.
  
  Low coolant level.
  
  Over revving or pulling excessive revs for a period of time.
  
  The motor running too lean, (not enough fuel or too much air).
   
• Q/ When I fit a motorcycle motor to my buggy, is the motorcycle radiator big enough?
  A/
  If you live in a cool climate you may find the motorcycle radiator sufficient to keep your motor cool.
  By a cool climate I mean no more than 27 degrees C, which is around 80 degrees F.
  
  A small car radiator works very well on motorcycle powered buggies.
  A radiator from a car with a capacity of around 1000cc up to 1600cc.
  A radiator with dimensions of around 350x350mm, (that’s around 14”x14”).
  
  Most late model cars have aluminium radiators which are nice & compact & are very lightweight.
  Often the radiator is mounted in the car on rubber mounts.
  It’s a good idea to retain the rubber mounting as this helps isolate the radiator from vibration.
  Most modern radiators have built in electric thermo fans; this is also a good feature that should be retained.
  
  Retain the motors thermostat & let the thermostat control the heat.
  This way the motor can not run too cold & as long as the radiator is a sufficient size, the motor will not run too hot either.
  
  When mounting the radiator care must be taken in its location.
  If mounted high try & keep it away from the drivers head.
  If the radiator is punctured with a stone or branch it could spray the driver with hot fluid.
  
  A radiator mounted sideways alongside the motor works well.
  Because you are using a car radiator the capacity to cool is very good, combined with an integrated fan air flow will still be sufficient to keep the motor cool.
  
  Always make sure that the top of the radiator is a little higher than the motors cylinder head.
  This allows air bubbles to form in the top tank of the radiator instead of the cylinder head.
  If air bubble became trapped in the cylinder head hot spots can form & cause severe overheating.
  
  Try & retain an overflow coolant bottle.
  A siphon overflow bottle system helps retain coolant & recycle the coolant back to the radiator once the system cools down.
   
• Q/ How do you keep an air cooled motor cool if fitted to a Piranha or Hypersprint..
  A/
  Keeping an air cooled motor cool when installed in the rear of a buggy.
  
  It is possible to keep an air cooled motors temperature down when installed behind the driver’s seat.
  It will never be as ideal as a water cooled motor but as long as the ambient air temperature is not too high it can be made to work.
  
  First modification of benefit is to fit an oil cooler.
  If you install an oil cooler you can use a car Auto transmission type.
  The best location is in the air flow away from sticks & branches that the buggy may brush up against.
  Also mounted away from stones the wheels may flick up.
  
  A car type thermo fan mounted in front of the engines cylinders is good for air flow at slow speeds.
  
  Air scoops ducting air to the motors cylinders helps keep the motor cool at high speeds.
  
  If the carburettors are re-jetted for more fuel flow this will also help keep the motors temperature down.
  
  Try not to run an air cooled motor on days where the ambient temperature is above 35 degrees C.
   
• Q/ Which side of the radiator do I mount the fan?
  A/
  Fans work much better sucking rather than blowing.
  
  If you mount a fan on the front of a radiator it will suck cool air, but then the air hits the radiator core & try’s to bounce back.
  The air is then trying to reverse its direction & slows the fan down.
  Very little of the air actually makes it through the core.
  
  This causes cavitation of the fan & a severe lack of cooling capability.
  With the fan on the back of the radiator the air is sucked through the core, the resistance the core offers loads the fan but no cavitation occurs because the air is then dumped to atmosphere.
  So the fan on the back side of the radiator is drawing air right through the core.
  Most radiator cores are multiple stacked, ie: two core, three core etc.
  This means the entire core has air flow passing over its surface.
   
• Q/ How do I install an oil tank to my Dry sump motor?
  A/
  Installing a dry sump oil tank.
  
  Preferred construction would be in Aluminium, although steel is OK.
  
  Volume of the oil capacity is not that critical as long as it’s as much, or more than the original bike.
  
  I would advise 4 litres as the extra oil will help keep the air cooled motor cool.
  (Just make sure you give the motor at least a minute or so to warm up before driving).
  
  Oil tank shape.
  A tall narrow tank is better than a long flat tank.
  Reason being is that you always want the outlet pipe to be covered with oil, so the motor receives a constant oil supply.
  The tank needs an outlet at the bottom which is normally a fitting that will accept a 3/8 to 1/2" oil hose.
  Another fitting at the top of the tank of the same size, this is the oil return line.
  
  A filling point on the top of the tank, a screw on cap is fine.
  
  A vent tube on the top of the tank of at least 1/4".
  
  (Yamahas run this vent to the rocker cover).
  
  Make sure you check the oil connections in the workshop manual.
  It’s important to get the connections the right way around as supply to the oil pump pressure system must come from the bottom of the tank.
  
  If you install an oil cooler you can use a car Auto transmission type.
  The best location is in the air flow away from sticks & branches that the buggy may brush up against.
  Also mounted away from stones the wheels may flick up.
  
  The oil cooler is best installed on the return line that feeds back to the top of the tank.
  This way it does not upset oil flow to the motors pressure system.
   
• Q/ What type of Fuel pump should I use on my Motorcycle powered buggy?
  A/
  Most motorcycle engines have a fuel tank mounted above the motor.
  This means the fuel supply to the carburetor is gravity feed.
  
  The needle & seat within the carburetors float bowl controls the amount of fuel that flows into the carburetor filling the float bowl.
  This needle & seat can generally only sustain 2-3 psi of fuel pressure before it will leak & allow too much fuel to enter the bowl.
  Over pressure causes the bowl to overflow & fuel then spills out of the carburetor.
  
  So the idea is to install a pump of very low pressure.
  
  There are two methods that work best.
  
  Method 1.
  
  A Vacuum pump.
  
  A Vacuum pump is a device driven by intake manifold vacuum supplied to a diaphragm within the pump.
  The Diaphragm pulses up & down & fuel flow into & out of the pump is controlled by simple inlet & outlet reed valves.
  This system is simple, cheap & requires no electrical power.
  As long as dirt is kept out of the pump the Vacuum pump will supply hundreds of hours of reliable service.
  
  The Vacuum pump has three main connections.
  Fuel feed in.
  Fuel feed out.
  Vacuum connection.
  The Vacuum connection goes to anywhere in the inlet manifold between the carburettors butterfly or slide & the cylinder head inlet valve.
  
  Some motorcycle carburettors have a vacuum port; this port is generally used on the motorcycle being connected to the fuel tank on/off tap.
  When the motor is turned over the vacuum produced opens the fuel tap.
  So this connection is a good port to attach the Vacuum pumps vacuum hose.
  
  The Vacuum pump is best mounted close to the motor.
  The fuel hose from the fuel tank is best fitted with a hand primer bulb; this is used to prime the vacuum pump.
  (same as used on outboard motors)
  After the primer bulb fit an inline fuel filter to prevent dirt entering the vacuum pump & carburetor.
  The then the fuel line is connected to the vacuum pump.
  
  Vacuum pumps come in two sizes.
  14 litres per hour & 35 litres per hour.
  The 14 litre pump is suited to single cylinder four strokes.
  The 35 litre pump is suited to two strokes & multi cylinder motors.
  
  Method 2
  Use a low pressure electric fuel pump to supply fuel from the main fuel tank via a fuel pressure regulator then to the carburetors.
  
  A pump of around 2 to 4 psi.
  
  A fuel filter should be installed between the main fuel tank & the electric fuel pump.
  
  Method 3
  
  Use a low pressure electric fuel pump to supply fuel from the main fuel tank to a small gravity feed tank above the motor.
  
  An aftermarket electric low pressure pump designed for a carbureted car is suitable in the region of 2 to 4 psi.
  
  The gravity feed tank only needs to be approximately one litre in capacity.
  The fuel pump continuously tops up the gravity feed tank as the fuel is used.
  
  The gravity feed tank needs an inlet fitting, (around a º” tail fitting) in the top of the tank.
  An outlet fitting of the same size in the bottom of the tank to feed the carburetor.
  An overflow fitting of between a ½” to 5/8” tail which is positioned æ the way up the side of the gravity tank.
  Onto this fits a hose which returns in a continuous downhill route to the top of the main fuel tank.
  A vent fitting on top of the gravity feed tank of around a º” tail.
  
  The main fuel tank must also be vented.
  
  Again a fuel filter should be installed between the main fuel tank & the electric pump.
  Another fuel filter between the gravity tank & the carburetors.
   
• Q/ Can I convert a kick start bike motor into electric start?, I have heard that The Edge have done this before?
  A/
  Yes we did fit an electric starter to a YZ490 powered Sidewinder, a very tricky job.
  
  We used a starter motor from an XJ650 Yamaha, we modified a small 35-1 15 tooth sprocket to fit the starter & chain drove the kick start shaft.
  
  As much reduction as possible is required between the starter & the kick start shaft to increase the torque.
  
  Mountings for the starter must be solid.
  You need to pull the side case off the bike motor & grind the stops from the kick start shaft & remove the return spring.
  
  But even with all of this there was way too much compression on the big single & we had to install a de-compression system to the head.
  
  I put the head on the mill & machined off a cooling fin & bored a hole into the combustion chamber, then screwed in a DT360 Yamaha de-compression valve which I had as a hand operated de-compression via a cable.
  
  Then it worked OK!!.
  But a YZ490 is a violent motor on the best of days!.
  
  Michael Steinocher installed an electric start to the RZ350 in his Sidewinder.
  Seeing the problems we had with the bike starter motor & its lack of torque he went for a high torque car starter from a Toyota Hilux Diesel.
  (Michael is an Auto sparky).
  But you need to make sure the direction of rotation of the starter motor suits the direction of rotation of the kick start mechanism on the bike motor.
  
  The main difference between a diesel starter & a petrol engine starter is the windings.
  Starter motors or petrol engines have small diameter copper wire, diesel starters have a large section flat copper wire.
  
  Michaels system worked a treat, he did not need a decompression valve, but then again the RZ being a twin does not have a great deal of compression per revolution as its a 180 degree crank.
   
• Q/ Why do most of The Edge buggy designs use square section tubing instead of round?
  A/
  Square section tubing is much easier to work with.
  It can be cut to size & the frame can be easily fabricated on a flat surface.
  
  In most lower chassis applications square section creates a much stiffer structure.
  
  Forming complex shapes from round tube is difficult.
  Not only do you need a pipe bender but achieving bends of the correct angle & distance with no twist is very difficult for a novice builder.
   
• Q/ What is Castor angle?
  A/
  Like most things to do with steering & suspension, they are driven by each other.
  That is, the individual design has certain requirements as to how its set up.
  Castor is important, especially on a buggy with a solid rear axle, (no diff).
  
  Castor is the angle which the kingpin is swept backwards. So looking from a plan view, (top) you would see the top of the kingpin further rearward that the bottom.
  
  As an example:
  With Castor, when you steer left the wheel not only steers but the wheel also sweeps downward.
  This causes the left front corner of the chassis to rise, thus throwing weight onto the opposite right rear wheel.
  That’s good because the right rear wheel is now getting more traction which steers you into the corner.
  
  One of the compromises is it requires more effort from the driver to steer the more Castor angle you use.
  
  This is because the action of turning the steering wheel is actually jacking up that front corner of the chassis.
  
  The heavier the buggy, or the heavier the front of the buggy the heavier the steering effort will be.
  
  In designing the Ballistic we opted for only 6 degrees Castor, (this is around what you would find on an average street car).
  This is because of the buggies weight & the forward seating position which increases the front end weight.
  We did not want power steering to be used.
  We achieved light steering & reducing bump steer by using more camber, the steering axis is dead in the middle of the wheels contact patch.
  Some would say that decreases the sensitivity the driver has, but for an offroad buggy steering inputs can be violent, & when racing for a long period that causes fatigue in your arms.
  
  On a light weight buggy more Castor can be used.
  This can be handy if you don't have a lot of power to get the rear end steeping out in corners.
  We go as high a 14 degrees on a 300kg buggy.
  But lots of Castor is terrible in reverse.
  Drag cars have lots of Castor, just watch a drag racer backing up after a burnout, if he's not careful he will find it difficult keeping it in a straight line.
  
  The front wheels tend to "fall over".
  Again another compromise in design, Castor is great as a “tool” to increase steering effort, but going fast in reverse can be very hairy indeed!
   
• Q/ Do Shock Absorbers really absorb shock?
  A/
  The Shock Absorber does not absorb energy, it dissipates this energy at a controlled rate.
  Distance & time is the rate of control.
  
  When you test a spring to find out its spring rate you are basically compressing it on top of a set of scales.
  The method is compressing the spring exactly one inch & measuring the force in pounds.
  
  Example: If you put a Piranha rear spring in a press & put some scales under the spring.
  Compress the spring by 1 inch.
  The scales will read 176 lb.
  
  The very nature of what we are doing here is getting a reading of how much tension this spring has, its also telling us that its transferring 176 lb of force to whatever is on the other side of the spring, in this case scales, in the case of real world installation its the buggy chassis.
  
  Keep compressing the spring & the tension increases.
  So if it was sitting on the scales you would see the load increase, same on the buggy, the spring is feeding this energy into the chassis.
  
  The spring is not absorbing energy, its transferring it at the rate it’s being compressed.
  
  So, in the case of the Piranha, compress the rear shock 1 inch & you have 176 lb of force at the top rear shock mount.
  This energy IS BEING TRANSFERED INTO THE CHASSIS.
  The damper only controls the rate of compression & rebound, so the spring does not compress too violently & does not snap back on rebound to violently.
  If the suspension had no damper it would become a pogo stick.
  
  Nothing in this system absorbs energy, all of the energy is being transferred into the chassis & some into the suspension arms & pivot points.
   
• Q/ What are the specifications of The Edge Shocks?
  A/
  The following details the specifications of The Edge Products shocks.
  
  Shock 390
  390mm eye to eye
  Spring wire 13mm
  Spring length 240mm
  Spring diameter 92mm OD.
  Number of Coils = 10
  Top eye is 1/2" rod end.
  Bottom eye is 12mm, 32mm wide Urathane bush.
  Shock stroke 90mm
  Shaft diameter = 15mm
  Body diameter = 54mm
  Spring rate 400lb
  
  Shock 465
  465mm eye to eye
  Spring wire 12mm
  Spring length 260mm
  Spring diameter 90mm OD.
  Number of Coils = 13
  Top eye is 1/2" rod end.
  Bottom eye is 1/2", 37mm wide Urathane bush.
  Shock stroke 110mm
  Shaft diameter = 15mm
  Body diameter = 54mm
  Spring rate 200lb
  
  Shock 750 R
  750mm eye to eye
  Spring wire 12mm
  Spring length 360mm
  Spring diameter 90mm OD.
  Number of Coils = 15
  Top eye is 1/2" rod end.
  Bottom eye is 1/2" rod end
  Shock stroke 190mm
  Shaft diameter = 22mm
  Body diameter = 44mm
  Spring rate 176lb
   
• Q/ Can I fit 25” ATV tyres to my Sidewinder?
  A/
  Fitting 25" tyres to a Sidewinder is going to do a few things.
  
  It will raise the centre of gravity; the buggy will be higher off the ground & less stable.
  
  Even compensating with the gearing, (fitting a 60 tooth sprocket to the axle instead of a 50) the 25" tyre will achieve more traction.
  It’s important with a Sidewinder to keep the rear wheels spinning in corners so it slides & does not hook up & want to roll over.
  
  That’s very difficult with a 25" tyre.
  
  The larger the diameter of the tyre, the larger the contact patch on the ground.
  This means that a 25” tyre will have much more traction than a 22” tyre.
  
  There is more profile to the 25" tyre, combined with a swing arm rear the tyre is more likely than a 22" tyre to tuck under, this can create instability.
  
  The extra diameter will also place extra leverage on the rear swing arm.
  
  If the rear ride height is not compensated for with the shock mounting position, a jacked up rear will cancel out a few degrees of the front steering castor angle & upset the steering, as with front to rear balance.
   
• Q/ Why do most buggies have skinny front wheels?
  A/
  Skinny front wheels are for dirt & gravel roads.
  The idea is to penetrate that surface layer of dirt & get traction on the firm ground underneath.
  
  Same as you see on a Rally car, they never run really wide tyres in the dirt.
  Wide tyres in the dirt can be like aquaplaning your car in wet conditions, you tend to float on that surface layer.
  When floating on that surface layer, you not only lose traction to drive you forwards, but you also lose your steering which tends to create understeer.
  
  In the sand you want a wider tyre to achieve floatation, because underneath that sand on a beach or sand dune, is just more sand!
  So the idea in sand is to stay on top.
   
• Q/ How fast will my buggy go, & how do I work it out?
  A/
  The buggies gearing & what it means to top speed.
  
  The following is an example of a CBR1000 Honda motor installed in a buggy.
  
  In the following we are assuming the motor tops out at 10,000 RPM, this is conservative considering the design of most modern motorcycle engines that are designed to rev very high.
  
  10,000 RPM divided by the primary reduction of 1.786:1 = 5599.10 RPM.
  
  (Primary reduction is the gear drive between the crankshaft & gearbox).
  
  5th gear, (and there are actually 6 gears) is 1.174:1 ratio.
  
  5599.10 RPM divided by 1.174:1 = 4769.16 RPM.
  
  Your final chain drive is 17-60 teeth, that’s a 3.529:1 ratio.
  
  4769.16 RPM divided by 3.529:1 = 1351.41 RPM.
  
  This is the speed of your rear axle.
  
  The 25x12.5x9" Bearclaw tyre has an actual circumference of 2050mm, (2.05m) at 8 psi.
  
  1351.41 RPM x 2.05m = 2770.39 metres per minute.
  
  X by 60 gives metres per hour = 166223.4.
  
  Divide by 1000 gives KPH = 166.223 KPH.
  
  Now that’s in 5th gear & it’s not an overdrive gear either.
  
  That’s not allowing for the fact that you can still shift up to 6th gear, & also not allowing for tyre growth which will also increase your speed.
  
  If for some reason you could not achieve 10,000 RPM, (and you WILL achieve it) because of wind resistance or its getting scary, lets say you only got to 8,000 RPM.
  
  You will still be doing 132 kph, (in 5th gear).
  
  There is not that much of a difference between bikes on gearing.
  Smaller bikes tend not to be geared as tall as they don't have the torque.
  
  I made a comment on the Customers buggy page that we had to fit a wing to our prototype Hypersprint because it was spinning its rear wheels at high speed.
  
  Believe it!!!
  There is that much power on tap.
  
  Once you get your bum in this machine its going to blow your socks off!!.
  So be very careful, these buggies are serious machines & should be treated with respect!
   
• Q/ What about Sprocket ratios, how do I work them out?
  A/
  Sprocket ratios.
  
  Tooth size V Ratio
  13-50 = 3.846:1
  14-50 = 3.571:1
  15-50 = 3.333:1
  16-50 = 3.125:1
  17-50 = 2.941:1
  
  13-60 = 4.615:1
  14-60 = 4.285:1
  15-60 = 4.000:1
  16-60 = 3.750:1
  17-60 = 3.529:1
  
  Example 50 divided by 13 = 3.846:1.
  
  Example: a 13-50 sprocket ratio means 13 tooth sprocket on the motor & a 50 tooth sprocket on the rear axle.
  
  This means the rear axle is rotating 3.846 times slower than the motor sprocket.
  
  A 13-50 ratio is considered a “low” ratio compared to a 17-50 ratio which is considered “tall” or “high”.
  
  Lower gearing such as a 13-50 ratio will have quicker take off acceleration & a lower top speed.
  
  Taller gearing such as a 17-50 ratio will have a slower take off acceleration & a higher top speed.
  
  As a general rule always look towards lower gearing as this will give an increase in low end torque & make the buggy easier to drive in boggy situations.
   
• Q/ Can I use a vee belt drive on my Go Kart?
  A/
  Belts are not a good idea on an offroad Kart for transmission of power to the rear wheel as you can not achieve enough reduction.
  
  When using a chain drive on the Raven or Fun Kart III these Go Karts have a 6.83:1 reduction.
  That’s a 12 tooth motor sprocket driving an 82 tooth axle sprocket.
  
  The 12 tooth sprocket is very small, (around 25mm diameter) but that’s OK because chain drive is positive drive, it can not slip.
  
  If you tried to reproduce this drive with a belt & pulley system the small pulley will be much too small.
  
  Vee belts & pulleys rely on surface friction, a small vee pulley can not transmit the power & torque without slipping.
  
  So you have to go to a bigger pulley, that means the secondary pulley, (axle pulley) has to be bigger as well to maintain the 6.83:1 reduction, (or thereabouts).
  
  So if you went to a 75mm diameter primary pulley on the motor, the secondary pulley would be 512mm diameter.
  That’s the size of a 20" tyre.
  Obviously this is much too large to be practical.
   
• Q/ How do I make my own extractors to suit a four cylinder motor ?
  
  A/The easiest way is to make the pipes four into one.
  
  Making the header tubes & the 4 into 1 collector larger than the standard exhaust system can be an advantage to increase flow & power.
  
  Because most four cylinder motors are mounted in the chassis offset to the right, (because of lining up the chain drive) this leaves more room on the left side of the buggy to exit the exhausts out.
  So the 4 into 1 collector sits on the left side of the motor around the same height as the engines cylinders.
  
  If you have the original exhaust system, retain the clamp flanges & the machined sections that fit into the exhaust port.
  
  Cut the pipes around 30 to 40mm out from the exhaust ports so you have four short stubs sticking out of the motor.
  
  What we then do is choose an exhaust tube the next size up that slides neatly over the original pipe diameter.
  
  You have the short stub pipes sticking out of the exhaust ports & you will also need a 4 into 1 collector, (some muffler shops sell these collectors).
  
  Using a piece of scrap flat bar you can fix the 4 into 1 collector into the correct position by tack welding, (or bolting) the scrap material to the collector & to the chassis.
  
  Now it’s a matter of joining the exhaust ports to the collector.
  
  Preferably what you want to do is keep all the exhaust tubes the same length, (tuned exhaust).
  This can be challenging as the exhaust port on the right side of the buggy is further away from the collector than the left side port.
  
  This means that the right side needs to take the straightest path to the collector, the port on the left side will need to travel slightly to the right & then switch back to the left to try & make all pipes of equal length.
  This will be the same for the middle two cylinders; each will have to switch back a certain amount to achieve equal pipe lengths.
  
  (A good idea here is to study pictures of race car exhausts, this gives a good insight into how the experts have laid out the pipes & achieved equal length pipes).
  
  Keep in mind that certain size tubing has a certain radius to its bends; often it’s not possible to have an ultra tight bend on say a 1 º” pipe.
  
  A good way of working out the pipe length is to use some thick wire.
  Bend the wire to the shape of the longest pipe, running the wire at the imaginary centre line.
  Bend a second wire exactly the same & cut to the same length.
  Now straighten this second wire out.
  This is the length that all of the pipes need to be.
  So now make sure you have 4 pieces of wire all the same length.
  You can now use these wires to create each length of exhaust tubing; each wire represents the path that each pipe will travel.
  Each wire is bent allowing for the correct exhaust bend radius & also must clear the other wires by at least the pipe diameter.
  Each wire follows the centerline of each pipe.
  
  Once you have four wires all bent to the correct shape & that travel from each exhaust port to the 4 into 1 collector you can now look at reproducing these wires into actual pipes.
  
  Two different methods of making the pipes can be used.
  
  1/ Make the pipes from readily available mandrel bends, i.e.: 45 degree, 90 degree bends etc.
  2/ Take your wires to an exhaust shop & have them bend each length from one continuous length of tube.
  
  You can make the system from mandrel bends purchased from an Exhaust / muffler shop.
  Example: buying some 45 degree, 90 degree, 180 degree & straight sections.
  
  Make sure you buy a few extra bends as the process can be tricky & mistakes can easily be made.
  Each bend should flow into the next, try & avoid sharp corners so there are no distinct corners in the system to interrupt flow.
  A Mig welder is very useful for tack welding each bend together; at least two tack welds are required per join.
  
  Keep in mind that you have to un-bolt the system from the motor once completed & that you have enough clearance to remove the finished product.
  Also make sure that you can get easy access to the exhaust flange nuts & studs that hold the system to the cylinder head, that no pipes are in the way of a socket or spanner.
  
  Before removing it’s a good idea to tack weld a piece of flat bar across all four ports.
  This is to hold the system firm & solid so the heat of welding will not distort & twist the pipes.
  
  Once the system is made from port to collector, remove the system from the buggy/motor & fully weld.
  The best form of welding is gas welding with an oxy acetylene torch.
  This gives small very neat tidy welds.
  
  After the collector a suitable size exhaust tube can be used from the collector up to the muffler location.
   
• Q/ How do I set up my pedals? Can I use a foot clutch?
  
  A/ Yes you can use a foot clutch, but a hand clutch is much easier & easier to use as well as much easier to set up. In this case the hand clutch is a motorcycle clutch lever mounted on the gearshift lever.
  
  You need to operate the throttle & the rear brake together when going fast into a corner.
  With your right foot on the throttle & your left foot on the rear brake pedal a foot clutch then becomes very difficult to use.
  
  Feathering the throttle in the corner keeps the rear wheels hanging out & sliding, tapping the rear brake is what initiates the slide, using the rear brake sets you up for the corner.
  
  Sometimes you continue to tap the rear brake in the corner if the corner gets tighter, while still feathering the throttle.
  
  In corners you stay away from the front brake, period, no exceptions.
  Using the front brakes in a corner will lock up the front wheels & you will understeer to the outside of the corner, out of control.
  
  If your revs drop too much you can simply fan the clutch, (hand clutch).
  If you have a foot clutch you can't do this & still control brakes & throttle.
  
  Also with a foot clutch you cannot do a hill start unless you install a hand brake.
  
  Perfect set up for pedals, (from hundreds of hours driving various buggies) is from left to right.
  Rear brake
  Front brake
  Throttle pedal.
  
  Clutch on the shift lever.
  
  Often the clutch is only used to start, stop & sometimes to get the revs up.
  This is because motorcycle motors have a constant mesh transmission, you can shift gears without the use of the clutch.
  
  
   

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