I walked outside lastnight with my 400ex running and my headers were glowing orange, is this a result of the bike running lean?

thanks

 

i got that happening on my warrior also.. at night it is visable.. i would like to know also.. ty!

 

im pretty sure its because its running lean...im just doulbe checking

 

Read this

----- Gimpster -----

 

It won't work for me.

The headers glow on my 400 and my YFZ. It is from being lean but wont hurt anything they come lean from the factory.

 

i see you have a 77 yamaha enduro 2 stroke, carlbadmuva, what is it , cuz i have a 77 it 175

how is the back suspension on yours if its a 175

 

I have a 77 Dt-400. the suspension is fine on mine. Ive been trying to find a spoke set for my bike now for my rear tire. I wasnt sure what model mine was we just knew it was a 400 but then we went looking online and found out it was a Dt-400. Mine runs really strong....but that website didnt work gimpster...can u try it again...and anyone else on the exhaust?

 

This topic has been discussed at least once or twice in this forum. I've noticed this phenomenon on several different makes and models. It's very noticable at night, if the machine sits and idles for a length of time. I think it's got more to do with idle speed being high than being lean. Some models will "fast idle" if left with the choke on, or half on (you know they're not lean then), and I've observed it under those conditions too. Your 400EX maybe lean, especially at low speed in colder weather, as this is a typical scenario, but I wouldn't jet based on the head pipe glowing at idle. Go for a short ride, get your machine heat soaked. Adjust your idle speed so it's on the low side, then slowly turn your mixture screw out and listen to the idle. If it picks up and smooths out, you're going the right way. Keep on going til the mix screw isn't helping the idle much, then set your idle speed to spec, or a comfortable idle. You'll very likely notice that richening your mix screw up will allow your machine to idle better at a lower RPM, without dying. If you end up more than four complete turns out from bottemed on your mix screw, or it makes no difference at all, check your pilot jet for obstruction, or possibly richen it up one size. There is a "quick and dirty" way to determine if you're lean. Again, get your ride warmed up (always when making or judging carb adjustments), and slowly apply choke at the suspected RPM range. If it runs better, you're definitely lean.

 

if they glow at idle, try turning the fuel screw out a little bit
if they glow when giving it a little bit of gas, drop the needle clip one position

 

alright thanks i will do what u guys said!


thanks