250r bores?

[dubs LT]

Im unfamilar what the boreable limit is for the cylinders on 86-87 and 88-89 250r models?

Also will the jugs interchange? 86 jug with 88-89 bottom end and vise versa?

thanks

dub

[trx250rkid]

the 86s have a shorter crank and taller piston than all of the other years. the 86 style piston comes in the largest overbore size which is .120 i believe (68.50 mm)
the largest 87-89 style piston you can get is .80 over.
Yes all of the cylinders interchange but make sure that if u have a long rod crank (87-89), that you have an 87-89 style piston or are running a spacer plate with the 86 style piston.