Hybrid Experience

[rustyATV]

Does anyone have experience with a two-stroke bike motor in a quad frame?

I'm mulling over the cost side of an idea and was curious what hurdles I'd hit with regards to vibration, driveline durability, gearing, etc.

The quad would be for XC racing and I'd use a 250cc two stroke bike motor from a 2002 or later bike.

Thanks

[BLACKeR]

few pro's used these you hardly ever see one built. there are reasons for it. if they were a hot set up you would see them.

[matt250r21]

The dirtbike 2stroke motors shake like mad in the quad frame. If your really interested, Service Honda stuffs an 02 and up CR250 motor in a 400EX frame. Check out their site. Nothing beats the real R though.

[TampaBoy813]

Originally posted by BLACKeR
few pro's used these you hardly ever see one built. there are reasons for it. if they were a hot set up you would see them. from what I understand they were outlawed....the built 250 motor was blowing away the 4strokers....

[BLACKeR]

from what I understand they were outlawed....the built 250 motor was blowing away the 4strokers....

the new production rules effectivly wrote out 250R's in general. before that it was pretty much "run what you brung" in fact the factory kawasaki XC team had a KX250 powered race bike they ran for a long time. but it odviously wasnt popular enough for anyone else to do. a good 265 motor will make just as much power and be a lot friendlier to you.

[rustyATV]

Originally posted by matt250r21
The dirtbike 2stroke motors shake like mad in the quad frame. If your really interested, Service Honda stuffs an 02 and up CR250 motor in a 400EX frame. Check out their site. Nothing beats the real R though.

Actually they use an '01 CR and my interest is leaning towards the case reed-inducted '02 and later with the servo operated powervalve, although having a forward kick would be nice. Also, I'm not really interested in a 400EX chassis; I'd like to get a hold of a 450R with a blown motor. Realize this is just an idea phase.

http://cgi.ebay.com/ebaymotors/Stolen-ATV-Quad-Honda-450R-TRX450R-250R-TRX250R_W0QQitemZ160023788853QQihZ006QQcategoryZ43 972QQtcZphotoQQrdZ1QQcmdZViewItem

I realize vibration is an issue, but Ballance, Yokely, and Smiley (?) were able to make the prototype at least bearable for the GNCC's.

I'd really like to know what steps were taken to dampen vibrations, their effectiveness, the durability of the driveline, and the difficulty in tuning the gearing for XC racing (based upon the fact that the tranny was designed for a dirtbike).

I've actually ridden a CRF450 Hyrbid and thought the vibrations weren't very bad, although that motor might be counterbalanced; I'm not certain.


Originally posted by BLACKeR
a good 265 motor will make just as much power and be a lot friendlier to you.

The Kawasaki prototypes were stock displacement, and regularly ran up front with 250R's sleeved to 300cc's or better.

Plus, new 250R parts aren't going to be around for much longer; aftermarket parts are already getting hard to find when you need them, which is why I'm considering this.