i'm new to this forum as of (3-10-05) and so far i love it! i have a '04 660r and want to have more low and mid. i'm going to drop a tooth on the front sprocket. but i want it to breath easier. i'm thinkin about a full exhaust like fmf power bomb header and a fmf pipe of some kind. if i do that how much would i have to jet up so i dont run too hot?

 

if you are running the stock air box you shouldent have to jet you should be ok. and the bet pipe for raptor is a full system yosh by far.

 

You would still have to rejet cuz u would be runnin to lean but listen to the other guy and just burn your engine thats smart go buy a dyno jet stage 3 jet kit for like 60 bucks and keep your engine runnin right!!

 

wow. so your saying if he gets a full yoshi exhaust and leaves the airbox stock he wount have to rejet?? wow. The yoshimura Comp-series is one of the best exhausts out their and a great price, 395$, also, dont get a slip-on as the stock raptor header is really bad.

 

Hes wrong u have to rejet or you WILL blow your engine or seriously hurt im talkin like 1200-3500 dollars worth of damage all of taht or you could buy a 60 dollar jet kit. You make the decision!!!

 

no hes not wrong.........the spec sheet for the comp system for yoshimura says if stock air filter and stock air box....no rejetting needed. HONESTLY....(i know i did a double take too)

i did mine a while ago and no motor problems at all. However air filter modification and rejetting will get the most out of your pipe though.

 

My spec sheet said i would burn up my motor if i didnt rejet with my pipe and i kept my airbox???????? But i alson have a raptor 350 not a 660r. That could be it!!!!!

 

The curtis sparks and LRD pipes have great power curves down low. The big gun is an excellent midrange pipe. Yosh is good on the bottom, too.

 

Before you do anything, you need to look in to buy a LTE dual exhaust system. This is the best system out there for a raptor it gives you 13 extra hp. The complete kit has everything you need. We have their systems on all our bikes (yfz 450, z400) check out their website lteracing.com. Not a bad price either, and the look you get is awesome So check it out. You will not be sorry, if you buy their system.