raced the atvprochallange this weekend.

[oscarmayer]

we ran the 70cc/cvt class with our 114cc engine. it was built to the mach and around 16hp, the 2-smoker CVT bikes passed him up w/o any problems at all. he was wound out in 4th gear most of the time and still not able to keep up. So after talking with some friends I decided to trash the 4-stroker engines and mount a kx65cc 2-smoker. Then have it bored to a 70cc and ported. Finally, I want to have a custom exhaust made to fit his frame and use this motor. So when done, we will have one heck of a fast motor for this quad. Next rules stated exactly as follows: "No manual clutches allowed" Semi-auto are ok(which is what we ran). So, I will install a Rekluse Z-start clutch assembly in order to give him semi-auto shifting capabilities w/o any clutch lever. the only downside is he will have to shift each gear by slightly letting up the throttle. That will just be him needing to get used to it is all. it can be in 1st gear and idle. i can even adjust when it engages so i can have it not engage till 3000RPM which gives him some launch capabilities. So in the end it will be a much better operation.

[Ryko racing]

we ran the 70cc/cvt class with our 114cc engine. it was built to the mach and around 16hp, the 2-smoker CVT bikes passed him up w/o any problems at all. he was wound out in 4th gear most of the time and still not able to keep up. So after talking with some friends I decided to trash the 4-stroker engines and mount a kx65cc 2-smoker. Then have it bored to a 70cc and ported. Finally, I want to have a custom exhaust made to fit his frame and use this motor. So when done, we will have one heck of a fast motor for this quad. Next rules stated exactly as follows: "No manual clutches allowed" Semi-auto are ok(which is what we ran). So, I will install a Rekluse Z-start clutch assembly in order to give him semi-auto shifting capabilities w/o any clutch lever. the only downside is he will have to shift each gear by slightly letting up the throttle. That will just be him needing to get used to it is all. it can be in 1st gear and idle. i can even adjust when it engages so i can have it not engage till 3000RPM which gives him some launch capabilities. So in the end it will be a much better operation.

We ran them for 3 years in our Cobras. Have to maintain the tolerance every moto but we never had one fail. Run em at a loose .032 and you can shift it with it pinned once he figures it out. The only issue we had was they wheelie off the line when they hit because you are setting at hi idle until he whacks it. Give me a call I can help you out. 734 664 2257

[oscarmayer]

that would be awesome! thank you sir!!!

[ontargetracing]

come on Mike.. 114cc in the 70 class..?? isn't the limit 90cc for 4 strokes. cheater lol

just buy a Cobra already

[bigdaddy77]

Im with Ontargetracing on this one. You are so limited with the Xtreme. They make a Bad *** flat track machine but they have such a limited suspension that with a superfast motor they will get a kid hurt on the MX track. Been dealing with this with one of our friends who have a pretty limited budget. Just my 2 cents but ask around and most Dads will tell you Suspension before motor.

[oscarmayer]

:p
well the rules do say 114cc 4-stroke and 70cc 2-smoker. but there is no way in god's green earth a 114cc 4-stroke is going to hang with a build 70cc 2-stroke let alone a build one. yes my 4-stroke was build but still could not hang. :mad:

I looked at cobra motors but them things are thousands and right this moment we do not have that kind of budget. i an getting the kx65 free. swapping one of my spare quads for it (i just need to install the 140cc manual clutch 4-stroke i got cheap into it. So that is why i am going with the kx65 (bored to 70cc). the rekluse will help keep it legal in the class. if i had the $ i would love to get a cobra. but financially i am not able too yet. the only reason i am able to get this kx65 motor is by trade. maybe if things work out i may put the bike back together sell it later and use the $ towards a cobra motor.

[bigdaddy77]

I think what we are trying to say is use a Cobra Chassis. They are lethal with the KX 65 motor. Fastest combination out there. My buddy has a Fischer mod and it has a hard time hanging with the Cobra KX65 combo. They are so light and have good suspension it's hard to compete. I've seen good riders on the the Cobra with single speed,shifter,and kx 65 motors run right with a bunch of good 90 mods.

[oscarmayer]

ahh ok, that makes sense. thanks!
yea I will look into that. For now just to get him used to the new type of engine, I'll mount it into the xtreme chassis till we get the $ saved for a roller cobra. unless you know someone selling one for around a $1000 or less, i will have to wait till next year on the roller, but at least we will be able to look at making him more competitive for now for sure!

Thank you everyone for all your help and advice! it really is greatly appreciated!

P.S. Sorry to hear about your cylinder Bryan.

[ontargetracing]

must be texas rules lol...

[nastynotchback1]

I got a Rekluse Z-Start fo the kx-65.Used it very little.My son did not like it.Make me an offer if your interested.

[oscarmayer]

pm sent

[Ride1Rob]

Where are you getting your dyno #'s from? Firepower is one of the best if not the best China engine builder around and his maxxed out 125's are getting 15/16 hp. You need to get with him on an engine package. Even if you have the hp the internal gear ratio on those engines aren't good for mx racing.

[oscarmayer]

yea better suited for CX racing it appears. lots of torque but no top end even with gearing done at best and turning 9800rpms.

we used a engine dyno a local shop has. at the flywheel it pulled those numbers

[oscarmayer]

Got the motor mounted into the frame even the stock pipe fits nice. Looks like it was made that way. It also sits back further which helps balance weight better. I think it is going to be a nice build.

[oscarmayer]

got a new hotrods crank and tusk clutch set. will be getting the cylinder bored to 85mm with custom porting done.
gonna upgrade to a 28mm PWK carb as well. will be a very nice build when completed and should scream like a banshie

[oscarmayer]

ok installed new hotrod crank and rebuild bottom end. installed new tusk clutch assembly as well. so now she ahs new gaskets, seals, crank and bearings. she will be ready for the 85cc setup. I will ship it out next week to get done.
I still have to buy a pwk28mm carb for it to boot. :( man $$$$$ flyin out of my pockets! :(

[oscarmayer]

pics!!
dad's new 180cc 4-smoker. (I have a typhoon I am doing up for me so I can chase my son around the track to make him run faster)
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Old 125cc engine. 15:1 compression and fully built
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kx65 test mounted into frame after I remove all old engine mounts
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bike assembled after mounting engine and pipe supports, everything fits like a glove!!!
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other side of the frame, you can see the mounts. I will be gusseting up the front mounts to support them better, but everything looks great and fits nice and snug!
1718107268