I cranked it up and let it warm up and the head pipe was glowing red. I shut it down and came here.
Any ideas?

 

lean jetting.

 

mine done this all I did was drain the oil it had a lot of gas in it so I put new oil in it cleaned the carb and it was good

 

I just brought it home tonight. You think I need to change the oil?
I was thinking pre ignition due to lean jetting. How do I adjust it weedman?

 

no you do not. Many threads state that their head pipes are glowing...lean from factory for emmisions standards.

 

Its caused by lean jet fron the factory, it will go away after the break-in and rejet. dont be worried about it.

 

All stock yfz and trx do this from the factory Also a brand new engine will build more heat than one that is broke in Just be smart and let the engine cool after about evry 20 min for the first 2 hr of riding and then start picking up the pace and ride it like your going to ride it

 

Like has already been said, do a search on this topic. It's very normal. They all do it.

Don't listen to everyone telling you it will quit after rejetting though. It will continue to do it after rejetting too. These bikes need to be ridden. They don't like to sit and idle. I usually let mine warm up for about a minute or so and then idle around taking it easy for awhile prior to riding hard.

Again, rejetting will not cause it to quit doing it.

Buck

 

Okay, thanks. I took it out of the truck this morning and have just been going over it before riding it for the first time. Crazy, I bought this and haven't even ridden it. Totally used to my DS that I just sold Tuesday.
Totally different. The Rotax was pretty much bullet proof and easy to work on if necessary. I hope this engine is as tough and easy to maintain. This glowing header thing tells me it's running lean and causing pre-ignition. Not okay on the DS. You guys are telling me it is normal and is supposed to run lean. I can't see re-jetting. I just bought it.
I want to spend the weekend and next to break it in. I have a race on the 25th in Gainesville, FL

 

I never worked with a YFZ but I know my 660 was very lean from the factory. It actually ran bad because of it. Something you might try is maybe going out on your air/fuel mixture screw a 1/4 turn but if its running good and the YFZ guys say this is normal, I'd probably leave it be.