Got a question about a friends bike. He bought a 2002 sporster. When he got it, the pipes looked new. He did a 1600 mile trip in 36 hours. His pipes turned dark yellow, darn near the whole pipe, the rear cylinder darker than the front. The inside of the pipe, front is black, the rear one is clean as new. Wiped my finger inside it and narry a smudge. I thought perhaps the rear cylinder was not firing, but when ran, it gets hot very quick and sounds like it it hitting on both banks. The throttle is very responsive, so it cann't be running on one?

This bike is also carbed, not EFI? Looks to be a high flow filter set-up, it runs like a bat outa hell, so I think it has been modded some, but he is clueless about it.

 

Have you considered asking the question in the Sporster Forum?

 

It's called "new guy in the shop". It's running 'rich'. Adjust air/fuel mixture & if that doesn't work, try reducing the size of the Main jet.

 

Ya, I thought about it. BUT, I've noticed the guys in this forum are pretty good with bikes. AND, a harley engine is a harley engine, regardless of what frame it's in.