Just had a 12:1 piston installed in my warrior. did the rountine break-in. no wot, no idling for long periods, let engine slow down quad ect for the 1st two tank fulls. the guy who did the install upped the jet to a 155. when i first got it home, i run it a litle bit and it would pop and sputter at higher rpms. firgured it was to rich with 155. also put in new plug, run it up in rpm in 3rd gear,pulled in clutch and shut it off. checked plug, it was black, too rich. put a 150 in it. went to dunes the next day, run it a while, and it didn't seem to run right. put in another plug, and did the same thing, plug was a little on white side in color. upped the jet to a 152.5, fuel screw out to 2 turns. seemed to run ok, put would pop some on deceleration. turned out scre another 1/4 turn, stopped the popping. now i'm on my 3rd tank of gas. my son and i were doing some dune chasing with some other riders. he was on the warrior, and i on the 450r. i noticed a little smoke coming from exhaust we he would let off some and then gun it again. told him to go back to camp to check things out. pulled the plug, it seemed ok, but the inside of exhaust tip was black,not just normal carbon, it was wet. checked the oil, it was just on the tip off dip stick.
Do u think there is something wrong with the rings , or could it be that they just haven't seated in yet? need any advice i can get. will contact the guy who did the work tomorrow.

 

*bump*

I have no idea, but I hope someone can give you a valid answer.

 

Sounds like either the rings or the piston to bore clearance is off. A compression check should help figure it out.

 

took it back to the guy you did the work, did compression check, it was about 110. should be 125-130. He thinks when installing the cylinder over the piston, he truned the cylinder a little bit and maybe aling the ring gaps. he going to tear it down tonight a take a look. he said he'd eat the labor and gasket set. he'll also recheck the piston to cylinder clearance again. if its out, he'll buy the oversized piston, but i'll have to pay for the boring. don't think that's to bad a deal. hope it's just the ring gaps alinged. will follow with the rest of the story when i get it back. thanks for the info.

 

got quad back today. The bottom two ring gaps were alinged. put it back together, got 160 on compression test. runs great know. have to re tune it tomorrow maybe have to rejet it up, since it's running better now.