jacobfour
05-31-2014, 09:31 AM
I got a 1984 honda 250r atc on last bore 72mm got Wiseco piston and getting ready to hav guy bore and hone and chamfer ports. Called wiseco and they confirm .002 piston to cylinder wall clearance. But I had talked to a small engine builder and he said he hates those ####n thangs and to go back to guy I bought it from and stick it up their ***. He said bc they expand to ### #### much. Now this guy is litteraly like 104 years old and maybe he's just too old. After talking to wiseco they said alot of people don't pay attention to the piston to wall clearance on the box and just do what oem clerence is and dont preform the heat cycles and that's when they run into problems. They also said if I wanted to go a little bigger like .0025 I should be fine. I guess my question is since this is last bore I'd like to only go .002 and do the neccary break n heat cycles and such and hopefully b ok. As opposed to going to .003 . Meaning the more bore the faster this last bore is gonna wear out. But I also don't want the piston to expand and boom goes the dynamite. Regarless I'd prolly stay half throttle for a while even after tons of break n cycles just to make sure. Any thoughts?