Don't it my exaust pipes blue

Mikey

got muscles in his head that ain't never been used
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After this summers motorcycle trip I noticed on my Triumph (liquid cooled 3 cyl) the tops of the exhaust pipes are turning blue on me
My 650 was rode just as far and probably just as hard but those pipes never turned blue
It must be heat doing it but is there a possible problem with it running to lean or to rich ?
Mike
 
You running the stock pipes? If so that's pretty much normal. They have an inner wall that keeps the heat down at the outer pipe.
 
You running the stock pipes? If so that's pretty much normal. They have an inner wall that keeps the heat down at the outer pipe.
Why not the air cooled Yamaha it's gotta run hotter
 
When I had my TX650 I had the original pipes and they were double skinned and never discoloured, I would imagine all standard pipes would be, if that is the case, as mentioned by Jim in post above, the inner pipes protect the outer and the heat doesn't get sufficient to contaminate the outer skin of the pipes.
 
OK... just reread your question. The Triumph afaik uses single wall headers. The XS is double wall. Both bikes will have (about) the same exhaust gas temp, regardless of air vs liquid cooling. The trumpets headers will discolor whereas the XS's won't because of the double wall pipes. So what you're seeing (on both bikes) is pretty much normal.
 
Yes, double walled headpipes were used to keep the outer pipe from turning colors from the heat. Your Triumph may have single wall pipes and it's normal for them to turn colors even if the bike is not running lean. The single walled aftermarket headpipes (MAC brand) I put on my '78 turned colors almost immediately after starting it. The single walled headpipes on my old BMWs also turn colors. The single walled aftermarket headpipes (MikesXS brand) I put on my '83 haven't turned colors and that has surprised me. Not that I'm complaining, I just expected it.
 
So first, lets clarify... is your XS running the stock exhaust headers?
both bike are sctock
OK... just reread your question. The Triumph afaik uses single wall headers. The XS is double wall. Both bikes will have (about) the same exhaust gas temp, regardless of air vs liquid cooling. The trumpets headers will discolor whereas the XS's won't because of the double wall pipes. So what you're seeing (on both bikes) is pretty much normal.
Thanks was just curious
 
Yes, double walled headpipes were used to keep the outer pipe from turning colors from the heat. Your Triumph may have single wall pipes and it's normal for them to turn colors even if the bike is not running lean. The single walled aftermarket headpipes (MAC brand) I put on my '78 turned colors almost immediately after starting it. The single walled headpipes on my old BMWs also turn colors. The single walled aftermarket headpipes (MikesXS brand) I put on my '83 haven't turned colors and that has surprised me. Not that I'm complaining, I just expected it.
Thanks !!
 
Also, on newer bikes there are emission systems like SAI that pump more oxygen to help increase temp to burn more unburnt fuel from the exhaust. So the headers will blue. On older bikes typically discolored headers tell you that you are too lean and your engine is running too hot.
 
Reading tips found on other forums, I sprayed Hi-temp black *inside* my new chrome pipes.
After about 4,000 miles, there's just a hint of amber near the header clamps...

2016-Vegas_RPW-Thor-13.jpg
 
Also, on newer bikes there are emission systems like SAI that pump more oxygen to help increase temp to burn more unburnt fuel from the exhaust. So the headers will blue. On older bikes typically discoloured headers tell you that you are too lean and your engine is running too hot.

Whilst the Secondary Air Injection will increase the exhaust temperature at the header IMO it is the single skin that is the prime factor.

If you look at the old British bikes before emission control had been invented it was normal to see blued exhausts particularly on the higher tuned bikes.
Just because the headers go blue it doesn't necessarily follow it is running lean.
 
I always understood that the double walled pipes do not discolor badly because the two pipes make point contacts with each other and this severely reduces the heat transfer efficiency. I wonder if the same applies to TwoMany's comment about spraying paint down the headers. The paint may just act as a fine insulation layer to slow heat transfer. Whatever the reason it works!
 
On the stock XS exhaust the inner and outer pipes only touch where they are welded together at the head and just before they go into the mufflers. If you look close you will see several holes drilled in the outer pipe up near the weld and down just before the muffler.
There is about 1/4 inch gap the full length of the header and all the way around the pipes. This and the holes allow cool air in between the two ;ipes to helpkeep the outer pipe cool enough not to blue.
Leo
 
249FE922-2528-4CBB-A319-61BDFF2558E3.jpeg You can’t beat a nice bit of blue on your pipes.
But I also think it’s a lot to do with the gauge of the steel the pipes are made from, and of course the quality of the Chrome.
 
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