We are a small team of motor mechanics and auto electricians working together to give the best customer service we can. 162-164 Newell st Bungalow.
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Make sure to use good quality wheel bearings with the extra clearance rating of C3 in the part number. They have less friction, especially when hot and particles like dirt and water etc get in, will not cause as much friction in them.
Also check your chain for any drag from guides, rollers, etc. Especially small sixe bikes as this robs power.
What a ripper! The fastest 50 made for racing so far.
The suspension is extremely good and the handing of this bike is great.
The bike comes std with Vforce reeds, a full circle racing type performance crankshaft and a insert type 2 piece cylinder head and adjustable ignition timing. The cooling system on this engine is very well designed, engine works well in sand as well as long tracks and also the ignition stator and housing is cooled really well to stop failures.
Best mods- HGS exhaust, reduce squish clearance, adjust slipper clutch tighter (70-80) use a good engine tachometer and adjust clutch engagement speed 8500rpm to 9500 for racing.
The suspension and handling is very good. The engine needs more power to compete in racing. The primary compression ratio needs to be changed, using stuffing to enhance the flow from the crankcases into the cylinder. The engine needs a better crankshaft , a full circle type race crankshaft. The powervalve is not adjustable in any way, except modifiying it , trial and error. The Carby is old fashioned round slide, and is not close to the engine induction. Comes std with Vforce reeds which is great.
Best mods – HGS exhaust works well. Crankcase stuffing required. Use the KTM type 24mm carby, and best to bore to 26mm, need to modify intake rubber boots and air cleaner boot.
The engine power is too high in the rev range for MX, ok for flat track.
Suspension,linkage change required as well as revalve and springs required for racing MX. The bike is now well out dated for racing, although very reliable and cheap to race. A great club level bike to learn skills , power needs to moved to get more bottom end for MX. Cylinder and head work required. The KTM sx65 is alot faster as the bike has a powervalve and better suspension. HGS exhaust and a vforce reed valve are the best mods for the engine, and with cylinder and head work the engine is very good for mx or flat track.
The basic bike is still a little behind the KTM sx85 in stock form but mods are easy to do on the bike.
Fitting the HGS or VH exhaust with the VHM cylinder head and special insert developed by BUD racing, the engine really performs well. Some jetting and needle changes are required for racing. Vforce reeds work better then the boysen rad valve.
Changing the suspension springs, a new linkage, and revalve to suit rider weight, the bike performs very well. The conrod weight is very heavy and needs to be reduced for top level racing. After the mods are done for racing you have a very solid bike that gives very little trouble. Overall this is probably the best mx or flat track bike as the performance is good and ongoing costs for racing can be low. This bike has much better brakes,throttle set up, rear suspension than the Ktm sx85.
Things to watch- run oil ratio at 30-1 for racing. Crankshaft oil seals wear if using some race fuels and you have to split the cases to replace them. The 2 ring piston is only good for trail riding or enduro but you can remove 1 ring for racing. The Vertex coated piston is better for racing. Overall bike weight is higher than the ktm, the gearbox is heavier than the ktm. There are areas on the bike you can reduce weight. ( gear tumbling works well for racing on the kx85) long term we will see more of KX85 on the racing seen.
Primary compression is correct (stock). HGS Exhaust, VFORCE Reeds. Reed Valve Spacer. VHM Head (stock jetting).
410main jet at 25-30deg- 420,-440 below 25deg standard needle and settings clip 3or4 and std pilot. mixture air screw 1.5
Note. This 125cc engine is very well designed and makes very good power for a 125cc.engine. Be carefull of different exhausts and silencers as different lengh can effect flow and can result in bad piston detonation (destroying piston tops) Some exhausts dont pull enough heat from the piston crown. We have found the HGS controls the temperature very well ,as in Holland they race alot in sand. You can check temperature readings at the spark plug on the Dyno when testing on maximum run up and constant/steady load- rpm. Also its best to have the piston cryogen treated, using a different brand can be better, we use Vertex, they are a little heavier than the std piston, but seem to last .
Yamaha 85s, lower the barrel to 30thou squish, raise compression with EHR head, don’t machine std head. Machine upper exhaust port upwards 15thou. Make the flywheel heavier with add on weights. We do a lot of work on crankcases to increase flow that gives more torque, we have EHR working on new parts for this engine. Scalvini Exhaust is great! Rear Swing Arm is too short for SHOCKY to function well. Hinson clutch is best on this engine.
Best Mods: VFORCE HGS – Barrell mods. VHM Head.
Fit the Scalvini Exhaust or HGS. Close squish to 28thou. Mods to cases etc. The RM85 doesn’t need a lot of work to improve it compared to other 85s.
Best Mods: RM85 use Powerband Linkage, Springs, Revalve. VFORCE reeds. HGS/Scalvini New 28mm carby.
Makes better power, use the JD jetting kit, changing the crankshaft mainbearings to one piece C4 rated bearings adds more power and more revs.
Fitting the VH exhaust, Vforce reeds, JD jetting kit, the 2017 is the fasted 250cc engine/bike available and easy to race, very little vibrations and easy to maintain.
The bike is lighter, better balanced , handles well and the air forks work well!
Unfortunately the engine power is less aggressive than the earlier 250s, but the engine is much smoother with almost no vibrations. For racing bests mods are ,fitting the Keihin 38mm sx125 carby will wake up the engine ( need to mod the intake boot) and the HGS or VH exhausts both add usable power. The exhaust port has some casting marks that need removing and the cylinder transfer ports have some lips that need removing. Vforce reeds are available.This bike will be easier to race in longer races, but a little slower than the 2013-2016 models in the engine department.
This bike is the best 250cc 2 stroke made so far ! Pulls like a 4 stroke and doesnt need to rev high ! Short shift or rev it, the engine is great.
Suspension requires work for mx, forks need to be better.
Best engine mods- VH pipe makes this bike a monster! Vforce reeds, VHM head, mod your own carby, boring and a much better needle, or buy a sx125 38mm carby, and fit the better needle and powervalve spring.
This bike is ideal for the club racer or the pro, but for long races the rider must be fit to hang onto the intense constance power delivery .
2017-2020
MODS- VH exhaust, VHM head and the VHM Piston work well. Vortex/get ignition with special maps.
This new lighter / slimmer bike is very good. The engine is all new, the lighter engine likes to be in the higher RPM. Piston squish clearance is a little too wide for racing. Early problems of crankcases cracking around the main bearing should almost be gone now. Checking-adjusting the crankshaft end float is wise when the engine is apart, some are too tight. The powervalve design does require more power now to drive it, and also can cause the power to drop off, and the rider may feel this. We have been using hard coating (nitriding) to have make the levers smooth.
Regular cleaning and greasing of the powervalve flap and rollers is required or they will stick in one position with some loss of power (best to do this before every race meeting!) KTM have made the powervalve very easy to get to, the linkages can be modified for better performance. Stock jetting is almost perfect. Using the older 2012- 2016 ktm sx125 Keihin carby on the 2017-2020 produces more power. The 2017 mikuni carb is jetted too rich and can be hard to keep tuned. Heavier riders may need to adjust gearing and do a few mods to make sure the engine stays in the higher RPM, as the revs drops the engine slows quickly.
Best mods- VH special exhausts, VHM cylinder head and the Vortex/get ignition with the special mapping works well, change the carby and intake boot on the 2017 best for racing. Carb boring works well. Using the VHM or the Vertex racing piston ( single ring ) adds more power. The VHM high inertia crankshaft is available now. Items to watch- gearbox is very lightweight, dont overload it, like a broken chain jamming it , gears will break. Only comes with the 2 ring enduro type piston.. Suffers detonation easily if not tuned well, powervalve can jam up after 10-20 hours, need to clean it.
Best mods:
The KTM / Husky is very fast after some simple mods are made (great bike). Easy to get parts in Australia.
The engine will run best with the HH carb needle on the 2nd clip postion and a 122-125 main jet and stock pilot jet. 30-1 oil ratio is required for this design engine, or failures will occur. There is too much open space area in the crankcases as the reed valve is too far from the crankshaft in this old design engine. Stock gearing will work fine for heavier riders and lighter riders can use a 15 engine sprocket. The bike handles better when the rear is lowered 15mm. The bike suffers from bad brakes. This is the fastest 85cc bike to race, but it requires the most upkeep, and its also the lightest engine and gearbox. Best mods are HGS or VH special exhaust, VHM head and carby boring. faster riders need to mod the clutch as they slip to much. Swingarm and Fork extentions work well for big wheel riders.General problems- running more oil is required, fast clutch wear and slippage, fork seals leak easy, throttle cable problems and the brakes can be a constant problem.
2018 -2020 SX85-TC 85 – 2018 had crankcase issues, but 19 and 20 models are just great. The best 85 ever made for racing. Normal engine engine mods for power increases, exhaust pipe, head, piston, reed valve , cdi, carby mods will give the rider a massive power increase, without mods to the bottom end at all. Some riders have well over 140 hours on a crankshaft, before rebuild time. best model ever! run a 140 main jet in summer, and a 145 main jet in winter, stock gearing is very good, clutch is great.
SX105 Big Bore kit, genuine KTM parts, the best kit ever made. well designed and what a rocket! just bolt it on, easy as ! Porting the cylinder, bore the carb and you have a real rocket! KTM really have a great design. Super FUN to ride, and seriously fast. ( the cylinder can easily been seen as different to the 85, so the 105 cant be mistaken for a 85.) Brayden Plath and Ky Woods are both riding the 105 , ask them why and they will grin big time, the bike is a blast! KTM engineering at its BEST!
KTM65 They left the anti surge washer out from under the main jet. This causes a bad bog on landing after a jump. The std carby needle is too rich, buying a jet kit is best if racing. The plastic water pump gear waers fast- about 30-40 hours and need replacement. The stock gearing 14-48 is fine for heavier riders, light weight riders will need a 47. Extending the swing arm and forks makes the bike handle better at speed, and easier to ride ( for faster riders) This is the best 65cc bike for racing and KTM have done a really good job on the design in most areas. Extra power is easy to get, bigger carby, VH special exhaust is great, VHM head with powervalve adjuster, CDI unit and you have a rocket! A very exciting bike to race when mods are done. The best 65 to race.
General problems- plastic waterpump gear wears fast, broken powervalves.(use the heavy duty one ) Oil in powervalve pressure chamber. Carbon in exhaust pressure outlet, use a cleaner oil. Water entering spark plug cap from pressure cleaning. carb needle too rich, fouls plugs. Fit a jet kit.
This is a 3 piece design ( like the Nihilo type) and can come apart . The powervalve hits in the bottom of the port sides , this slamming down damages the powervalve , But from 2017 you have a small threaded connector ( the 3rd piece) installed, we have had this piece fall back inside the engine and cause damage. Using the VHM powervalve and the special base is best. Take care when fitting.
