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Discussion Starter #1
So I installed the Cobra FI200AT, the Vance and Hines big radius 2 into 2 exhaust and an LA choppers XXX BAK this weekend. After I got everything on I took it for a test ride (about 120 miles), everything feels good, and it sounds awesome, I did notice some popping and a couple of backfires when compression braking, but I thought that was probably normal.

When I got it home I was looking it over and i noticed some discoloration, (slight bluing?) on the first 4 inchs or so of the front header pipe. Not on the Heat shield, but on the header beneath it.

Has anyone else seen this? or have any thoughts?

My main concern is running too lean. During the exhaust install we tested for leaks, and all seemed good to go.

Thanks in advance!
 

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Which engine? If you have a complete aftermarket exhaust with no catalytic converter you may want to think about removing/disabling the AIS also, after considering the legalities. The AIS can cause your symptoms including the blueing especially if the exhaust is already RICH (yes, rich). The fresh air exposure greatly increases the exhaust temperature in exhausts with a lot of unburnt gasses. For most its not an issue, but for some the AIS can cause this. There is no performance to be gained from removing it, just the decel popping and backfiring and a cooler exhaust. If the AIS is already disabled, have the lines blown or are otherwise leaking?

Here's your link. You didn't think I knew this on my own, did you?

http://www.vstar1100.com/jack_phelps/vstar/ais.htm

That's the best I can do without knowing what you have.

You could also be lean, but that's less likely with an AT tuner. There is an adjustment to richen idle, but I'm not familiar with it.

More intelligent peeps than me should pipe in. I'm just thinking out loud again.
 

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The AIS is probably a good start after ensuring you have no other leaks. The AT does have an adjustment despite being advertised as plug n play. Calling Cobra would steer you better than I can on that. The AIS delete is likely to be a top culprit for the blueing most ways you squeeze it. It's hard for the AT to lean out your bike when it's function is to constantly tune you for optimum power. That 2-2 exhaust can to a lesser degree. More so without a crossover pipe and/or too little back pressure.

I'm just killing time until someone with better advice comes along.
 

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Discussion Starter #6
Well I appreciate any advice I can get, although I just got back from taking a little closer look at the header pipe, and it would appear as though the discoloration has a very hard line to it, it covers half the circumference of the pipe, and stops exactly where the first hose clamp is for the heat shield.

In other words the discoloration is exactly where I would expect it, if some ham fisted amateur (me) was wrestling the exhaust into place, and didn't wipe his handprints clean enough off of the header before it was ran.

I have always taken it to the same mechanic (for services and such while it was warrantied), who is a pretty cool guy, so I plan to swing by and see if he can take a look tomorrow, mainly for peace of mind.
 

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Discussion Starter #7
Update for anyone interested.

I took the bike down to my mechanic (Yamaha dealership), who has a fair bit of experience with this combination of parts, and he said that everything I was seeing is normal:), and complimented me on the install.:D

I figured I was just being a bit paranoid, but it is nice to have confirmation.

Anyway, thanks again for all of the advice and suggestions.
 

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you never answered if the bluing only occurred after you installed the mods. if so, then i would disagree with it being normal. it would definitely mean you are running a lot leaner mixture than before, when you should be running a richer mixture instead.
 

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Discussion Starter #10
I installed the pipes, the intake and the fuel processor all at the same time.

Or were you asking if the stock pipes were bluing as well?
 

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Delete the AIS system and then get back to us. The discoloration is from your bike running to lean. The discoloration is caused from a lean bike running hotter exhaust fumes.
 

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Discussion Starter #12
Is the AIS removal procedure the same for a fuel injected 950 as it is for the 1100. All of the research I can find seems like the 1100's are the ones needing this mod, no write-ups on the 950, and doing a search here seems to show some disagreement about whether it needs to be removed on the 950's?
 

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The process should be the same, if not and you are anything that a weekend mechanic can handle you will be fine. It cant hurt to remove it, all it does is introduce fresh air into the exhaust for the silly EPA. I used .45 cal shells to block the holes or you can spend the $20 and buy rubber stoppers.

If you just want to test to see if it makes a difference, you can take the rubber hoses that run from the chrome tube to the unit and just loop them back on each other. That will save you time and tell you if its really worth it.
 

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Glad you got piece of mind! My 1300 did the same thing with subtle backfiring when coming off high speeds, bluing of the pipe itself and not the chrome cover. I would also suggest taking it to a dyno shop if there's one near by. They will be able to see everything thats going on with the engine etc. even make some adjustments. You've already spent big $$$$ whats another 100 bucks!
 
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