im looking for some ideas here so help me out if u can ..ive just finished doing to top end rebuild basically everything u see in my sig ..for so reason the front pipe seemed to turn black or dark blue before to rear..what i was thinking is it possible that the front exhaust cam could be off a tooth ? how do u think the bike would run if thats the case ? what about checking this ..think i could remove the rod tubes put the front cylinder on tdc and see if i could turn the rods with my fingers ? I'm sure i could take the top boxes off and measure the valve hight..then compare the 2 .. Ive checked for intake leaks but seems good ...both plugs seem about the same maybe a tad lean think about going up atleast 1 maybe 2 on the main ...what about the compression would there be a difference if the cam was off ? I did talk to NRHS but there kinda stumped without looking at the bike them selves they did mention pretty much what i said above ..anyone got something for me ..i forgot the say the bike runs good over all no smoke only got 25 miles so far with this cold weather..front cylinders got 140 psi and the rears got around 150 .. i realize that all this i just wrote is a bunch a mumble but if u got something let it fly ..trying to hold off ripping the thing back apart for nothing ...god bless

I will give you a bump. I am not sure but I would think if the cams where off a tooth it wouldnt run or worse you would get some contact somewhere. I just did cams and heads on my 86 and I am have a hard time fine tuning it and was wondering the same thing. Hopefully someone will jump in with an answer.

Just too chime in with a helpful bump.
did you do the cam install?if so did you TDC then line up the cam dots?
Are these stock pipes?just thinking different metal.
Blueing is caused by heat.maybe too lean a air fuel mix?lean = hotter condition(I'm probably wrong on that)
Then lastly something could be up with the vavle?(seat?)
just throwin this stuff out there:dunno

I don't think the piston has to be at TDC to line up the timing marks on the cams. I just installed my V04 cams, and the front piston was a little before BDC or so, with all the marks perfectly lined up. The pinion gear needs to be at afound the 10:30 or 11 o'clock position to match up with the #2 cam gear. If the front piston was at TDC, the mark on the pinion gear would be at about 6:00 (I'm guessing...)
also, the HD manual says NOTHING about the piston being at TDC, and neither does the Clymer book.

Also, if the cam gears were off a tooth, the bike would run real rough, to the point that you say "damn, what's wrong with this thing?"

It think you should try upping the jet size by one or 2 (the most) and set the idle mixture...at least within reason...

Ur right the pinion wasn't at tdc close but not quite ...i pretty sure I'm not off on the cams just wanted to throw that out as one of my ideas ..i richened up on the main jet [72] and retarded the timing alittle ..im not gonna worry anymore till i get it on a dyno ...then every thing will be out in the open ..thankx for Ur input