is my timeing off?

after puting a new crank in my 01 yz426 it starts fine but after about one min. of it running the header pipe starts to glow red hot. there is also a crack in the header pipe could this cause it

All 426s have red hot headers if they are allowed to idle in place for long. This is clearly visible in the dark. If this is happening sooner than before it might be possible that you have a crankcase air leak.

All 426s have red hot headers if they are allowed to idle in place for long. This is clearly visible in the dark. If this is happening sooner than before it might be possible that you have a crankcase air leak.[/QU

i bought this bike with a blown crank so iv never seen it run so i cant compare it to before but this seems to get red very quick in the day time

YZF headers get hot when they sit still idling, its normal. Just as long as they don't get as red as Grayracers header. His is smoking hot, hopefully he'll post a picture of it. :banghead:

YZF headers get hot when they sit still idling, its normal. Just as long as they don't get as red as Grayracers header. His is smoking hot, hopefully he'll post a picture of it. :busted:

is that his 03 yz450 that hes tring to sell lol i knew there was a reason :banghead: lol

All 426s have red hot headers if they are allowed to idle in place for long. This is clearly visible in the dark. If this is happening sooner than before it might be possible that you have a crankcase air leak.
How would a crankcase air leak affect a 4-stroke, especially one with a half inch hole for a breather already?
YZF headers get hot when they sit still idling, its normal. Just as long as they don't get as red as Grayracers header. His is smoking hot, hopefully he'll post a picture of it. :banghead:
Stop bagging on my header. It's normal, I tell ya.

rocket-cart_sm.jpg

Stop bagging on my header. It's normal, I tell ya.

Thanks Gray. I needed a good laugh after spending most of my day getting frustrated lacing rims in my garage.

What's the frustrating part? I can't do anything about tedious, but I might be able to help with frustrating.

How would a crankcase air leak affect a 4-stroke, especially one with a half inch hole for a breather already?

Never thought about that, just knew it is a problem with two strokes. Learning more everyday! Sorry :banghead:

How would a crankcase air leak affect a 4-stroke, especially one with a half inch hole for a breather already?

Stop bagging on my header. It's normal, I tell ya.

rocket-cart_sm.jpg

that is bad ass and a cool ride :banghead:

Never thought about that, just knew it is a problem with two strokes. Learning more everyday! Sorry :banghead:
In a two-stroke, you'd have something. The crankcase there is a part of the intake tract. OTOH, an air leak in the intake tract of a 4-stroke WILL cause lean symptoms, just as with a pinger. The intake just doesn't include the crankcase, that's all.
What's the frustrating part? I can't do anything about tedious, but I might be able to help with frustrating.

It was my first time lacing wheels from scratch. I got them almost perfectly trued, but it was a headache....

I think they look pretty good, and the wife is happy! (which is all that really matters....right?)

yz290f021.jpg

yz290f019.jpg

I also put on some new backgrounds and a new exhaust system...

yz290f014.jpg

Now, only one more set to lace up for my bike....

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