The brown pipe mystery

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**** Mystery solved! I took the bike to have the sniffer test done today. The data shows the bike is lean at idle and the guy says that is completely normal and by design to meet EPA standards. As soon as you give it gas the mixture goes to right where it should. Everyone who said it was probably due to letting it idle to charge battery was dead on and now I can explain why. I am a happy camper now that i have concrete proof to explain the discolored pipes. Thanks again to all those who provided useful helps, especially Fred W., ionbeam, and radiohowie.
I remain (cautiously) unconvinced that merely idling the bike 15 minutes now and then would blue the pipes so severely on an otherwise healthy bike.

Now, if you'd told us that you forgot about your idling bike and left it going for over an hour or more, then I'd say that might do it. ;)

 
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Honestly I don't want to rain on your parade, but I not so cautiously agree with Fred. The impression that I got about

the amount of idling you have done does not explain that amount of discoloration.

It just don't feel right.

But then again a buyer may buy it. :unsure:

BTW you don't buy gas at Corny's do you? ;)

 
Honestly I don't want to rain on your parade, but I not so cautiously agree with Fred. The impression that I got about

the amount of idling you have done does not explain that amount of discoloration.

But then again a buyer may buy it. :unsure:
I didn't keep a close eye on the time, I just used 15 minutes for the sake of conversation. The guy that did the test today has been in the motorcycle engine building/performance business for 20 years and said he definitely thinks the idling was the cause of the discoloration. I have to say based on his opinion and that it is a fact the mixture is lean at idle but fine with throttle, I believe that to be the problem. Can you provide any other reasoning?

 
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Honestly I don't want to rain on your parade, but I not so cautiously agree with Fred. The impression that I got about

the amount of idling you have done does not explain that amount of discoloration.

But then again a buyer may buy it. :unsure:
I didn't keep a close eye on the time, I just used 15 minutes for the sake of conversation. The guy that did the test today has been in the motorcycle engine building/performance business for 20 years and said he definitely thinks the idling was the cause of the discoloration. I have to say based on his opinion and that it is a fact the mixture is lean at idle but fine with throttle, I believe that to be the problem. Can you provide any other reasoning?
I disagree, but if it makes you feel good with what the mechanic tells ya. Go with it. ;)

 
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I remain (cautiously) unconvinced that merely idling the bike 15 minutes now and then would blue the pipes so severely on an otherwise healthy bike.

Now, if you'd told us that you forgot about your idling bike and left it going for over an hour or more, then I'd say that might do it. ;)
As a service to the FJR community, I am starting up my bike right now...and will leave it overnight.

If it's blue, I will post up.

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<I am not really serious about this, but brown pipe threads make me nervous and twitchy.>

 
I've never seen pipes looking like that and have a hard time believing it is caused by idling. Did you check for a mouse nest in the air filter box? That would give you a rich mixture causing the CATS to go into after burner mode. The sniff test may not show the rich problem due to the relatively small throttle required to rev it up in neutral. You said it wasn't like that when you got it......something has changed.

 
I've never seen pipes looking like that and have a hard time believing it is caused by idling. Did you check for a mouse nest in the air filter box? That would give you a rich mixture causing the CATS to go into after burner mode. The sniff test may not show the rich problem due to the relatively small throttle required to rev it up in neutral. You said it wasn't like that when you got it......something has changed.
+1 On that ^

When I bought mine it had not been run in more than a year. I opened the air box and it was full of mouse nest and s#!t. Lean mixture blues the pipes from the head down not after the cats! This is a rich mixture problem plan and simple. If the mufflers were restricted low air flow would restrict RPM's. 5k - really - the damn thing doesn't start to breath well till 6k. Get your tools out and take a look or all this great advise, not mine, is for nothing.

 
Am I missing a page to this thread? What ever happened to the Blue Pipe saga?

 
He sold the bike to Jeff (FJRGuy), who rode it part way home up to Ontario a week or two ago. link

Not sure if motoquest cleaned them up before the sale or not. But I guess we'll get a look at it next spring (at CFR).

 

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