Carb jetting mod pipes

[Fasted]

I bought my Valkyrie last fall with 9K. I was looking for a quite bike (I'm aging). Mine had OEM pipes but wasn't as quite as I though it should have been. After some research I figured out that my pipes had the piggies cut and both baffles drilled. I pick up a unmodified set of IS piped and wow the bike is quite. :-). In getting the modified pipes ready to sell I noticed that the headers for cylinder 3,4,5,6 are have started blueing and 1&2 are trnished. The unmodified IS pipes with more than twice the milage look like new. No blueing or tarnishing.  That tells me the motor was running lean with the modified pipes. What I've read that with cutting the piggies and drilling you didn't need to re-jet the carbs. With the blueing I think the bike was running lean and needed re-jetting. What do you guys think?

[9Ball]

could have been run too long with the enrichener (choke) or left to idle in the garage without any air movement over the pipes.  Pretty unlikely/improbable that it was ever running lean.

[98valk]

could have been run too long with the enrichener (choke) or left to idle in the garage without any air movement over the pipes.  Pretty unlikely/improbable that it was ever running lean.

+1

oem pipes are double wall, it has to be extreme leaness or richness to cause the discoloring.

[Ricky-D]

I've been with "holed" out stock exhaust for five or six years and a 6 degree wheel, pipes are yet to show any change in color.

I'm with something else, has had to have been changed, and/or too much idling!

Not sure if quality of gasoline making that small a difference could cause the color change.

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