Blue exhaust pipes

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Blue exhaust pipes

FlyboyTJ
I'm looking for my first CB 750 and want to make a good decision when I purchase one.
I looked at a nice 750C that had blue pipes where the exhaust tubes come out of the
engine. Is this a sign that the engine has been running lean? Running to hot?
Do I stay away from a bike with blue pipes?
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Re: Blue exhaust pipes

woodsrider250-2
IMHO, this is inevitable on a bike that's running perfect.  It could mean it got lean, but a lot of times no.  Need to look at other things like plugs, etc.
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Re: Blue exhaust pipes

OTTODOCTOR
    You didn't say whether or not it has factory exhaust or aftermarket . The factory uses double wall headpipes , which almost never turn blue unless they get REALLY hot . This could be fuel related or could also be an indicator of slow ignition timing as well . -- The single wall aftermarket exhausts will almost always discolor to some degree , and would not necessarily be anything to worry about . -- Pull a spark plug and look at the color on the insulator . If it's a pretty brown/tan without any black speckling she's running pretty good .
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Re: Blue exhaust pipes

Re-run
Administrator
This would be wrong. My 78k pipes are blued a little and it is completely normal. The 78 and subsequent years were made to run lean. If your plug is is brown, it is running too rich and not giving the performance it should. Starting on the 77, plugs should have a light dusting of tan at the most.
the whole brown/tan thing is a hold over from earlier years where carbs were not as good and needed to run a little rich to work right.
The ride IS the adventure. The destination is just to get gas!
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Re: Blue exhaust pipes

OTTODOCTOR
   I guess I missed it by one shade of tan , sorry guys .  
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Re: Blue exhaust pipes

FlyboyTJ
In reply to this post by Re-run
Thanks for the reassureance fellas, I'll check plugs to see if they are tan.
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Re: Blue exhaust pipes

Re-run
Administrator
A LIGHT tan.
The ride IS the adventure. The destination is just to get gas!