Hi everybody, I just received my powerbomb headers yesterday. I just put them with my powercore 4 and wow, it make a huge difference compared to stock. It revs so much faster and now I can make a wheelie when im in the 4th gear.I realize how the stock exhaust were very restricted. I have 22 inch dirt devils and a 14 front sprocket and it pulls the gearing easily. I was really suprised because with the stock one, I could hardly shift into 5th because it would bog. Thats my experience and I hope everyone enjoys it. I'm very happy with the fmf combo and I would give it 10 out of 10, and yes its very loud! If you have a question, dont be shy and ask it! lol

 

You did rejet, right??? If not, you are lean and can toast your engine!

I have always run FMF full systems on all my big sport bikes, and have never been disapointed!

 

no i didnt rejet because everything goes well. It doesnt backfire, and it runs very strong across the powerrband. I'll rejet soon when i'll put my k&n filter/no lid and with the hotcam stage 1. But do you think i should rejet now?
thanx, Joel

 

I just discover one thing....when I let the raptor run for some minutes at idle, the headers are RED. And when I turn it off, it backsfire a lil bit. Is this normal?

 

Plain and simple explination really... your too lean.

 

Do have any jet size recommandation?

 

should have come with main jets, if it did then remember those jets will get you in the ball park IF you are running with the air box lid off.

 

Have you had a look at your plug yet? What is the colour?

 

I didnt check the plug yet..I have the dynojet kit thought....but do someone know what jet I should put?

 

And are u sure that I need to put jets in it because it runs perfectly....like.....if I let it idle a long time...the pipe will turn red...but right when ill start to go forward, the pipe becomes normal...its weird