1. Dismiss Notice
  2. Hey Facebook people... We've created a group for XS650.com members to connect. Check it out!
    Dismiss Notice

Don't it my exaust pipes blue

Discussion in 'The Garage' started by Greyandridin, Nov 22, 2020.

  1. Greyandridin

    Greyandridin Got nothing to do and all day to do it XS650.com Supporter Top Contributor

    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
     
    gggGary and Jim like this.
  2. Jim

    Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

    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.
     
    gggGary and Greyandridin like this.
  3. Greyandridin

    Greyandridin Got nothing to do and all day to do it XS650.com Supporter Top Contributor

    Why not the air cooled Yamaha it's gotta run hotter
     
  4. Jim

    Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

    So first, lets clarify... is your XS running the stock exhaust headers?
     
    Greyandridin and rbt1548 like this.
  5. rbt1548

    rbt1548 XS650 Member

    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.
     
    Greyandridin and Jim like this.
  6. Jim

    Jim Beyond the edge is the unknown. Here be Dragons XS650.com Supporter Top Contributor

    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.
     
    gggGary, Mailman, Paul Sutton and 2 others like this.
  7. 5twins

    5twins XS650 Guru Top Contributor

    20,186
    12,268
    813
    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.
     
    gggGary, Mailman, Paul Sutton and 2 others like this.
  8. Greyandridin

    Greyandridin Got nothing to do and all day to do it XS650.com Supporter Top Contributor

    both bike are sctock
    Thanks was just curious
     
    Paul Sutton, Mailman and Jim like this.
  9. Greyandridin

    Greyandridin Got nothing to do and all day to do it XS650.com Supporter Top Contributor

    Thanks !!
     
    Paul Sutton likes this.
  10. 123petey

    123petey XS650 Member

    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.
     
    Greyandridin, gggGary and Jim like this.
  11. TwoManyXS1Bs

    TwoManyXS1Bs BBQ Hunter Top Contributor

    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
     
  12. Max Midnight

    Max Midnight XS650 Addict

    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.
     
    Jim, Greyandridin and gggGary like this.
  13. Paul Sutton

    Paul Sutton Still Looking Good Top Contributor

    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!
     
    Jim, Greyandridin and gggGary like this.
  14. XSLeo

    XSLeo XS650 Guru Top Contributor

    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
     
    Greyandridin and Paul Sutton like this.
  15. Rasputin

    Rasputin XS650 Addict XS650.com Supporter Top Contributor

    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.
     
    Greyandridin and Jim like this.
  16. Rasputin

    Rasputin XS650 Addict XS650.com Supporter Top Contributor

    0BDFC4AE-D638-4604-AFBA-AB81F1820004.jpeg Stainless steel goes a lovely golden straw colour.
     
    Paul Sutton, rbt1548 and Jim like this.
  17. rbt1548

    rbt1548 XS650 Member

    Lovely bike, does you credit. Still on the hunt for one here in the UK.
     
    Paul Sutton, Rasputin and Jim like this.
  18. Rasputin

    Rasputin XS650 Addict XS650.com Supporter Top Contributor

    I can’t take any credit for the bikes condition, that’s down to the previous owner, Kevin Brown,who restored it.
    But I do keep it clean. Oh and the odd crank.
     
    rbt1548 likes this.

Share This Page