PDA

View Full Version : piston mark



jimbo1073
07-29-2012, 06:09 PM
will this mark on this piston affect anything??? its like brand new. rebuilt motor and can not get it to run right. misses in mid range and no top end. changed the whole electrical system rejetted many times. up to a 178 now. before rebuild and bore i was running 168 main jet. new reeds also. ive rebuilt this motor several times and never had this problem. should i rebuild the carb? what can possibly cause it to run this way. its runnin lean but when i move the clip to the leanest position(top groove) it runs better.still not good at all. ? 87 trx250r fmf pipe, 80over wiseco piston,cool head (21 dome), no airbox lid, Vforce reeds