How long is the connecting rod on the KLX 250s?, same as 300 also I guess. I want to calculate the rod stroke ratio to see if it can be improved, and if "stroking" it would cause to much side thrust and friction. No pun intended.

 

Stick with the tried and true. I.E. Bill Blue you want good output with good reliability. It's not hard if you have the bucks and facilities to make a monster KLX250S, but do you want a klx250 monster engine that self destructs every 25 -40 hours, and requires major case machining just to make parts fit, nah didn't think so.

 

The KLX 300 and 250s have the same connecting rod. I don't know what that rod length is though. When Stroker Inc. was in business and selling a 365cc kit, they kept the stock rod but offset ground the crank. There's not much room inside the cases, so I wouldn't imagine that you could gain very much in stroke without hitting everything as the crank rotates.

www.fourstrokeworks.biz is the modern incarnation of Stroker, Inc. You could call Jerry Leighton and ask him about it.

 

props, i was just thinking about this. i came from the land of hondas (cars) and im looking into this for my d16 build (even looking at a 1.7 stroker using 100% honda oe parts). not to do anything crazy, just make the motor work a little easier at 7200 rmp. try to find an engine spec sheet, they should have rod length some where on it.

 

Honda cars are where I got this idea, I have three of them now and 2 in the past. The B 16 has an ideal rod stroke ratio of 1.7 (I think). The KLX rod is belived to be 107mm (I just found out), which gives it about a 1.75 ratio. So stroking it wouldnt hurt, but I like that long rod and would just leave it. To bad we cant get a piston designed like Endyns roller wave Honda! maybe a Honda piston would fit? making it a 400cc bike! probably not tho. Laters