My buddy has a YFZ and has a factory 4 pipe on it, he has been riding with it quite a few times with the pipe and has no problems up until this weekend. He said that there was no problem in the bottom, but when he goes to pin it, it sputter, has no power, and wants to cut out. He had the dealer re-jet it when he first got the pipe. I dont know if this is good, but they put a 146 Main. is that too small? any help is appreciated

THanks

 

He should be at about 165-170. that is way smaller than stock. Stock is 158

 

so if it was too small could it have F**ked up his motor?

 

NEVER go to the dealership for work that is not covered by warranty. local private shops will do good work so you will come back again. stealerships f*ck your **** up so you have to come back!

 

It could if he keeps riding it that way. It will run really hot and eventually melt a hole in the piston

 

But the instructions he got with the pipe said to put a 142 in, and then he went to their website and it said 152.
and when he put the 152 in it wont start.

 

Goto http://www.yfz central.com/invision/index.php?showtopic=908&st=0 Without the space between z & c