YZ125 Motor in a YZ85 Frame?

[Caseys500]

I've searched everywhere but can't find anything on it...How difficult would it be to put a YZ125 Motor in a YZ85 frame? Has anyone done this? The reason I ask is I did my own CR500AF conversion (I had the machine shop fab and weld in the front motor mounts but I did everything else) and I think my wife would be better suited riding a 125 but the height is too tall for her. Thanks!

 

[XRpredator]

if it'll squeeze in there, and if the swingarm pivot is relatively close, I say go for it. Keeping the bigger engine cool might be an issue, unless you can find a way to put the dual radiators on the littler machine. Pipe routing is another bugger, as I'm finding out with my own little conversion:

http://www.dirtrider.net/forums3/showthread.php?t=149478

another option might be putting the smaller wheels on the YZ125, but it'd probably look funny. There's also lowering links available. check here:
http://www.mountainmotorsports.biz/

 

[2 strokes for life]

Caseys500, i have looked into this many times befor and i will say it can be done, but will be hard. Like Pred said it might over heat and the pipe fitment will be diffecult. I think a older air-cooled engine might work better and be cheaper. Just go get an old IT200 engine, pipe, carb, and airbox. Good luck.

 

[Caseys500]

My wife loves the 2 stroke though...she won't even consider anything else, we found a 2005 crf150 for $1500 and she just likes hers better...The 4 stroke motors are just too heavy for her, that's the only reason I was thinking YZ125 motor.

 

[2 strokes for life]

Caseys500, like i said do a IT200 engine or older air-cooled YZ125 engine.

 

[IndyMX]

Why don't you just have Eric Gorr bore the YZ85 to 112?

 

[Caseys500]

That's another option too...I guess I just like morphing things. With a 125 motor, then it could be bored too. I wonder if they make a kit for the YZ85 like they do for the CR250 (the 330 kit) Something like that would be perfect!