How do you know you need to rebuild your bottom end? I have had my 250R for a couple years now. I have done one top end and plan on doing another top end very soon. But I was thinking does my bottom end need to be rubuilt also? Might as well do it while it is apart already? How much would it run to have it rebuilt? Thanks for the help guys.

 

If you are going to have it apart, then you should at least change the crank seals. If they are leaking this will make the motor inefficient (since that loss of vacuum causes loss of fuel and air intake.

Bearings, crank play, tranny gears and shifter forks should be check especially second gear on the main and counter shaft (M2 and C2).

I can suggest that you buy the service manual for the R and with that in hand, it gives you all the specs you should check for if something needs replaced.

Just be really organized when you tear it apart and you shouldn't have a problem.

Good luck