is it really a big deal if i dont put new jets in my bike. have a pipe and i wanna put on my yfz but every one is saying i need to put jets in do i really have to ?

YES!!!

your friends are right. the pipe manufacturer should have givin you specs for the jetting. it also depends on what air box configuration you are using! Call up the pipe company, tell them what you have...and they should get you real close.

Why put on a pipe at all if you don't want the full benefits? Adding a pipe and not jetting the bike will get you no more performance and usually less than stock. It wiull just make you louder and a loud stock power bike is

ITS NOT THAT HARD EITHER.... AND WAYYYY WORTH IT

You definetly need to rejet with a pipe. The yfz is lean from the factory. Putting a pipe on without jets will make it worse. If you have an open airbox with a k&n, and a pipe, try a 45 pilot, 175 main. If you have a sstock airbox with a foam filter, I would try a 168, or 170 main with the 45 pilot.

BUST OUT WITH AN AIRBOX TOO. K&N OR WHATEVER THESE GUYS THINK IS BEST

Said it all.

Actually, when I got a pipe on my EX couple years ago, didnt rejet it for the first time, made way more power than stock, then when I got it jetted made some more power. If you get exact on jetting, you will make more power. Most guys that ride dumont,glamis,pismo and have yfzs that pipe, filter start off 170-175 MJ, 45-48 pilot, 4th clip on NVCQ (yz needle) and 1.5-2 turns air screw.

You just got to play with it, I started out with a 175 and 48 pilot but it was way to much, and I have the filter and everything so then I ran a 170 with the same 48 pilot and it runs perfect, it just depends on the pipe, and everything else you have running on it.

thats a big 10-4