Gloving red exhustpipe and white sparkplug

I finally got my 426-00 starting after some promblems. I took it for a test drive and i run really well, exept for a little bad throttle responce on the lower RPMs. But after I saw that the first 5 inches of my exhustpipe was gloving red and late noticed that my sparkplug was white were the spark comes from.

Anyone knows what problem i have?:bonk:

Bike is running lean.

Welcome to Thumper Talk. The glowing head pipe is normal and a FAQ. In the upper right of your screen is a search button. Search for "glowing head pipe" and you will get lots of hits. The spark plug being white could be from a lean condition, but spark plugs are hard to read in modern 4 strokes, IMHO.

Spark plugs are nearly impossible to get any sort of meaningful reading from with unleaded fuel. Only the very lowest point along the base of the insulator where it meets the shell has any color that can be "read" reliably. You can take a biike that runs perfectly well on a 165 main jet and put a 172 in it and still pull a white plug.

The glowing header is normal, too. Search on the keywords "red" and "header" and see what you get. It's caused by a combination of the extremely thin titanium header tubing, aggressive cam timing, and retarded ignition timing at idle, especially in neutral. It should be a distinct red in about a minute or two in low light situations.

Unleaded gas doesn't normally color a spark plug......To get any reading from your plug most tuners use some race gas mixed in with the pump gas or just use someones after market race gas with the correct octane for the application. Like mentioned above thin titanium exaust headers will glow red.....Now if it melts off.......then change your jetting..ha ha ha


show us the picture gray..... it's been a week or so !!!!!!!!!!

show us the picture gray..... it's been a week or so !!!!!!!!!!
Back by popular demand!


sweeeeetttt !!!!!!!!!

thanks gray

Oh boy:crazy: Is that you, Gray?:bonk:


no. :bonk:

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