Topic: Pipes yellowing, plugs color looks good...

[rshinall]

I've asked this question on my other thread about throttle bogging, but I thought I would start a new topic as well. I've read a few posts on this but I still can't quite make sense of my situation.

I've done a lot of tuning recently - air screws, needle clips, slow jets, main jets. She's running really well...and the plug color is good...BUT...

The #2 pipe is yellowing a good bit (right where it exits cylinder head)...#1 doesn't seem to be, and #3 and #4 are just a little. Should I be concerned? Even with a "perfect" tune, won't all pipes start to discolor?

Thanks for the input!

[trueblue]

When I fitted new pipes to my 650, on the first start all pipes went a bronze colour within about 30 secs.  They have stayed that way since.  My headers are single wall stainless which has a tendancy to bronze with heat.