is this normal??

[bigwake]

so i finally finished working on my 03 yz450f i bought..fired it up 2night in my garage and the pipe was firey red! pretty cool!..and then once the bike warmed up and i adjusted the idle back down..i was hitting the throttle a little and a 6 inch flame shot out the back of the muffler..is that normal? the bike had been sitting a while..any help? thanx-josh

[CaptainKnobby]

Your jetting maybe a little on the lean side.......When I say jetting I mean the jet needle. You may want to take the jet needle out and put it in the #4clip position,start at the top of the needle and count the # of rings down and see where the clip is at,if it is not in the #4 then try it there to see if it takes that fire shooting out the exhaust out. I bought a DRD full exhaust system for my 06 and had the same problem.When I gave it gas fire would shoot out the exhaust about three feet. So I had to richen up the jet needle a bit.......just one clip position. Hope this helps out

[bigwake]

i may be wrong..but i don't think that's what happened..my bike i sall stock..and has never been opened or adjusted..but i will look into it! thanx!-josh

[642MX]

Grayracer had the same problem. I think he has a picture of it..... ?

Maybe he'll be kind enough to post it.......

[bigwake]

haha i wouldn't mind seeing it ?

[crazyal426]

Stainless header Yamaha thing. They all do it on initial fire up. You only notice it if you are looking and the lights are down. Check your plug to be safe, but this happens to all of them.

Good luck!

[bigwake]

thanx! and yes..it was in the dark so i could see the light of the pipe very well..and i had just put a new plug an doil and radiator on the bike..maybe it just needed to wake up! haha..-josh

[pmoravek]

I just bought an 01 426 and it does the exact same thing.

(Only the glowing..although the flame thing sounds pretty cool)

I was a litttle concerned, but I am told it is pretty common.

[grayracer513]

Grayracer had the same problem. I think he has a picture of it..... ?

Maybe he'll be kind enough to post it.......

It's 100% normal, especially with a Ti header.

https://www.thumpertalk.com/forum/showthread.php?t=236304

Like 642 said, mine does the same thing. (where's GA426owner?)

[jayh300]

i love that pix..... get the marshmellows and wieners boys !!!!!!

[crazyal426]

You might be a redneck if.........

hahaha

You rock Grey!!!!!

[grayracer513]

You might be a redneck if.........

??

[642MX]

It's 100% normal, especially with a Ti header.

https://www.thumpertalk.com/forum/showthread.php?t=236304

Like 642 said, mine does the same thing. (where's GA426owner?)

I still laugh when I see that picture.........

[Motocroser67]

maybe there isn't a spark arrester in there