[BillyCRF-450X]

I have a 05' CRF450X, air box mods, JD kit with 160 main,,pilot jet , red needle on # 3 from the top, accelerator pump , thick O-ring,smog pump still on and operational .I'm at 5000' and ride 5'-9'.

So I installed everything with the stock pipe (Baffles out)Starts,Idles and the bike runs like a raped ape! Till today.

The wife surprised me today and bought me a new FMF pipe so I installed it and fired her up.

The bike is back firing,popping and throwing flames.
I know it's a lean condition but wanted to give you guys a shout and see what you thought.

[Asmith]

I think you didn't replace the crush gasket between the head and the new header pipe. Air leak is causing a major lean condition.

[BillyCRF-450X]

I think you didn't replace the crush gasket between the head and the new header pipe. Air leak is causing a major lean condition.

Hmmm Your totally right about that.
The reason I didn't put it on was because it was a real tight fit,so tight I had to loosen the header up completely to to get it on.
I will give that a try and see what happens.

Ty for your reply and I will give ya a follow up to what happens ..

[BillyCRF-450X]

I think you didn't replace the crush gasket between the head and the new header pipe. Air leak is causing a major lean condition.

So your talking about the header to the head right?

[BillyCRF-450X]

I pulled the header off to make sure that it hadn't fallen out.

So you believe that this is causing the problem because I didn't replace it with a new one?

[amaviper]

I pulled the header off to make sure that it hadn't fallen out.

So you believe that this is causing the problem because I didn't replace it with a new one?

Exactly... Can re-use on same header pipe and it works most of the time. New header pipe - you need a new gasket.

[BillyCRF-450X]

I pulled the header off to make sure that it hadn't fallen out.

So you believe that this is causing the problem because I didn't replace it with a new one?

Exactly... Can re-use on same header pipe and it works most of the time. New header pipe - you need a new gasket.

Well I think I found out what happened.
I had my son helping me during this install and when he tightened the header up he crushed the gasket on one side.
It seems to be this causing all the problems being the bike ran great before this.

Ty again for the help.

[BillyCRF-450X]

Ok, I'm at a total loss.

I replaced the gasket with a new one and the bike is still doing the same thing.


Anyone got an idea or suggestion?

[mikey526]

Ok, I'm at a total loss.

I replaced the gasket with a new one and the bike is still doing the same thing.


Anyone got an idea or suggestion?

Don't let your wife buy bike parts for you any more...

[BillyCRF-450X]

Don't let your wife buy bike parts for you any more...

Thanks for the laugh ..

I'm pulling the pilot to check that out.

[BillyCRF-450X]

So took off the header for the second time and replaced yet another exhaust gasket and pulled the pilot jet just to make sure everything was fine even though she idle's fine.

Got the same thing going on. Pops on deceleration with a small amount of flames.

I'm starting to think that it's the smog pump causing this now.

Possible right?

[paul turner]

So took off the header for the second time and replaced yet another exhaust gasket and pulled the pilot jet just to make sure everything was fine even though she idle's fine.

Got the same thing going on. Pops on deceleration with a small amount of flames.

I'm starting to think that it's the smog pump causing this now.

Possible right?

170 main
4th clip JD Red
2.25 turns out at fuel screw.

Remove the smog crap or fill with JBWeld.

paul

[BillyCRF-450X]

Double

[BillyCRF-450X]

[/quote]


170 main
4th clip JD Red
2.25 turns out at fuel screw.

Remove the smog crap or fill with JBWeld.

paul[/quote]

The stock header studs were bent and the header had a dent in it so I just ordered a FMF Powerbomb. First thing in the morning before I pick the header up I'm pulling apart the smog pump and JB welding it. Do I put the diaphragm back in or just leave it out?
I'm at 5500' and ride from there to 9000' , I will give it a try and see what happens though.

[BillyCRF-450X]

Took your advise Paul and did the things you mentioned and OMFG!!!!!!!!!! I have this : ) on me face and can't get rid of it.
So after doing the smog pump,170 main,moving to #4 on the needle I fired her up and took her for a ride. All was good besides having some de-cel popping which bringing the F/S to three turns out got rid of it.

Once again ty for the help everybody...