I have just installed a powerbomb header and and a DG exhaust and now the header is getting bright red up by the head. Doesnt this mean it is running too lean and will have to be rejetted. If so how do i know what jet to use? Any help would be appreciated. It is my understanding that I do not need the entire jet kit. Thanks

 

raising the needle will do midrange..main jet does top end mixture

 

if its running to lean bring your main down a size or to

 

<div class="FTQUOTE"><begin quote>Originally posted by: sbaker72

I have just installed a powerbomb header and and a DG exhaust and now the header is getting bright red up by the head. Doesnt this mean it is running too lean and will have to be rejetted. If so how do i know what jet to use? Any help would be appreciated. It is my understanding that I do not need the entire jet kit. Thanks</end quote></div>

plug run highly reccomended. 99% of the time after any intake or exaust modification jetting is required. more like 99.9999999999999% of the time. you should take a plug run. Now on the other hand my buddy had a full Yoshi racing exaust on his warrior and at night it would glow red but it was jetted fine. but yeah definatly should do a plug run and most likely re-jet after those mods

 

Thanks guys, I appreciate the input. I did see another post and someone recommended a 170 main jet, does this sound right. What exactly do you mean by doing a plug run? Thanks in advance for taking your time to help me out here!


Shawn--97 warrior

 

A plug run is where you put a new plug in it and go ride for a little while then come back and pull your plug out and look at the color on the end of it that's in your combustion chamber. You want a medium light brown color. That's how you know that it's jetted right. If it's black: too rich. If its white or light gray: too lean.

 

like said, at nite most will glow. not sure on a 4 stroke but on a 2 stroke u do a plug chop by being in 2 or 3rd wide open and killing the bike. white plug =lean brown= good= black and wet= rich. alot of times if your lean it will pop and back fire, rich will bog on you. remember this time of year cold weather will make you run alittle leaner,(not sure where you live)

 

Thanks guys, I actually had it out today but cant really open it up, dont have plastic on it right now or seat, rebuilding, but didnt seem to get red at all and just riding in the yard seemed fine, but that is some great info, i really appreciate it.

 

I'm working on a 02 Raptor 660 Limited Edition, Black and Red(not mine, I'm a Suzuki guy). Installed the Big Gun Evo X full pipe, and jet kit. Headers are glowing bright *** red on IDLE!!! That to me means a LEAN condition. Main jets are 148L 150R, idle jet is still stock 22.5, but after getting frustrated about the glowing headers, we poked the idle jet out to around .028, and now it is entirely WAY TOO RICH on idle. Infact, so rich that at 3 turns on the idle mixture, it would barely run, and even the idle speed screw is turned in fully!!!

First we fire it up, and starter to dial in the idle speed, and believe me it RAPS up FAST with the 22.5 idle jet in, but the headers were glowing red hott after about 4 minutes of idle. Would going up in idle jet size be the way to go, or keep working with the bored out 22.5 jets?? If going with different jets, what size should I go with??? I have to wait til Monday to get them, tho......

Thanks guys.

 

id go up some..... was your exhaust poping or back firing ? id go up 2 sizes on your pilot screw and go from there. where do you live, remember, cooler air will make you bike run a little leaner as well. when you have a thread about jetting showing your elevation helps others trying to help out. good luck !! my buddy has 3 raptors and he's always messing with the jetting !!!