Exhuast port carbon buildup

3 replies to this topic
  • bbeakley

Posted October 12, 2001 - 06:29 AM


I have a '00 426 which means I take the header off to remove the oil filter (I love that design *grrr*). When I did this, I noted a buildup of black carbon gook in the exhaust port just prior to the header pipe. Is that normal or should it be cleaned? If so, how do you clean it. I didn't see any mention of this maintenance in my owners manual. It's an even film that's smooth, but it's built up to maybe 1mm in thickness (hard to say for sure). Again, any advice would be appreciated.

  • jaybird67k

Posted October 12, 2001 - 07:01 AM


I had the same problem until switching to Quality race fuel, now its clean and white and also no more fouling problems.
I cleaned my header pipe with carb cleaner and a rag on a string, the carbon in the exhaust port will remove it self after going to race fuel.
Dont forget that this is a high performance race engine and this requires HP fuel, regardless of the marketing schemes provided by Yamaha to help sell more bikes to the masses.

Later, Jason

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  • Roostie_1

Posted October 12, 2001 - 07:28 AM


BTW- you shouldn't have to remove your header to change your oil. Next time just loosen the header a bit and it should slide out of the way just enough to remove your filter.

  • bbeakley

Posted October 12, 2001 - 09:49 PM


Thanks Roostie. That's actually usually what I do, problem is I like to have the engine warmed up so that all the little particles are suspended in the fluid and drain out. If the engine is cold, all the crap settles and you don't get it out. BUT, since the header gets HOT when the engine is warm it would be nice if you didn't have to touch it at all. I'll keep my eyes out for an '01 header for sale and upgrade first chance I get.

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