glowing #3 exhaust header tube

A friend of mine has a 83 KZ650 CSR. He just got a new after market exhaust after the originals rusted out. He says when he starts the bike the #3 header pipe glows. Too rich?..too lean? what may cause this. As for the carbs we have both agreed they need to been cleaned out thoroughly since it has not been done. Any info would be greatly appreciated.

Sounds like it is too lean.

bountyhunter wrote:

Sounds like it is too lean.

+1, sounds like you have a debris clogged #3 carb.

ditto x 3

You should do a compression check on the engine and get some baseline numbers to ensure still good operating components.

It takes some serious lean-ness to make the header pipe glow, and this can spell trouble for alot of other components.

When cleaning the carbs, blow carb cleaner spray through all the jets and passageways while visually verifying the spray coming out the jets/ports in the carb with a nice clean powerful flow. Ideally when finished, the spray should look the same through all passages/carbs.

You should be able to hold the jets up to a light and actuall see the cleanly defined taper inside, even in pilot jets, unless your eyes are bad. Then they're clean.

Make sure carb-engine holders are bonded/airtight firmly in place with some Permatex Motoseal or #2 gasket maker, as they are impervious to gasoline.

Best of luck.