Question for the 500AF guys

[stevea100m]

Hey guys I'm trying to build a Kx250AF putting an 03 motor into a Kx250f frame. I was wondering why you guys go with the 250F frame and not the 450 frame? Is it a width thing as to why the smaller bike frame? Any help you guys could give me would be greatly appreciated

[don46]

I've not done the 250f/500 conversion but have done the 450f/500 conversion so I could only speculate, I have done a 250f/250 2t conversion, I do think the Showa suspension is better than the KYB stock, the 250f is a bit more compact than the 450, thats a plus and a minus, plus because it handles incredible, minus because it is shorter than the 450 and with 500 cc's sometimes you need the length (you could use a 450 swingarm as they are longer) beyond that the only thing I could think of is that they would be easier to come by. I also think it would be more work to put the 500 motor into the 250 chassis over the 450 chassis.

[stevea100m]

Well my main thing is with putting the 250 ts motor in an aluminum frame, is that i can find a ton of 450 frames and very few 250f frames. I wasnt sure if just the cradle area was different or if the frame width is different as well.

[Danger4u2]

Service Honda offers the 250 2 stroke in the 250F chassis.  Sounds like your on the right track.  Find yourself a 250F chassis and let us know how it goes.  I saw that you posted with J-Fab he should be able to help you with the head stay also.
 
http://www.servicehonda.com/kx250af.html

[stevea100m]

Thanks Danger that and john dowds bike are where i got the idea once i get all the parts around i plan to do a build post on it so you guys can see how it progresses