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STrumpet in hot weather

Discussion in 'Technical and Troubleshooting Torque' started by burna, Nov 30, 2012.

  1. #1 burna, Nov 30, 2012
    Last edited: Nov 30, 2012
    Triumph Sprint ST starts playing up on really hot days. Was in the Melb CBD yesterday in 39C (yes it WAS mental!), the bike had been fine but then started missing n stalling at the lights. Had all the symptoms of fuel vapourisation. The bike was hot but not overheating, was one maybe two bars higher than normal on the temp gauge.

    It has done this once or twice on cooler (but still quiet warm) days.

    Any others have this problem? Any suggested fixes, other than ride it on cooler days?

  2. Traditional short-term cure for fuel vaporisation is to keep a full tank, or (even better) fill up with cool fuel from a servo's underground tank. Park in the shade, too.
    Is the fuel pump anywhere near the exhaust?
  3. Yea tanks was about 3/4 full. AFAIK the fuel pump is in the tank but will have to check the manual to confirm.
  4. Had some thing similar on my 955 turned out to be an air leak
  5. make sure your thermo fan is working too....
  6. Yea I plugged it into tuneECU and checked the fan and is working fine.
  7. And it was only causing problems on hot days?
  8. Yep, the revs would be all over the place and running like shit. Traffic lights and junctions would see it bouncing from 800 to 2000.
  9. Interesting. That's what mine was doing yesterday but stalling too. Do you know where the leak was?
  10. I have suffered 'vapour lock' whilst riding out Western NSW in 45 Degree heat, IMO I don't think your problem is this, as you stated it has occurred before on cooler days.
    I'd be looking for crud in your fuel or blocked filters (or even a batch of bad fuel)

    goodluck, interested to hear what it turns out to be.
  11. I'm pretty sure it's not bad fuel or crud bc it runs smoothly the rest of the time. Even yesterday it was running sweet all day until we hit Kings Way heading for citylink. I had come down from northern suburbs just before and parked for about half an hour. We rode up St Kilda rd n it didnt miss a beat until Kings Way. Once I got a little forward speed it was fine, I am thinking more fuel flow thru the rail??
  12. My Daytona will stall occasionally if I'm sitting in traffic in the heat - symptom of no air cooling or flow through the radiator and low idle speed. Don't think it's actually anything wrong with the bike, as it runs fine when I get going and is never an issue in cooler temps.
  13. You will find owning a Japanese motorcycle will usually fix the problem. LOL

    PS - Apologies to the OP, I don't have value to add to your question as I have no experience with Triumph. Please take the above comment in the right spirit. I couldnt help myself :)
    • Like Like x 2
  14. I was wondering if it was just a case of the Pommy bike wasnt designed for that sort of heat! :p
  15. I'll see if I can find the invoice. Cos I cant remember.
  16. May be I ahould mention oil leaks before anybody else does :mad:
  17. Might be time for a coolant flush. I ride my sprint around in qld all the time with no issue!
    Nothing tricky, but there is a specific sequence to follow on the sprint (maybe all the 1050s?). Ill dig it out of my notes for you when I get home tonight. It's specific because of how easy it is to get an airlock etc.

    Fuel vaporisation though hrm... Never had the issue... Ill look into and think on it some.

    Oil leaks on a triumph? Pfft! :p. None on mine...

    Ok, have you inspected the radiator, hosed it out to make sure all the cores are clear for airflow? 7 bars on the gauge is fine when in traffic. It's not running 'too hot' until it has 9 bars and starts flashing at you.

    Did you open the fuel tank? Was there a lot of vacuum pressure when you did it?
    • Like Like x 1
  18. The radiator appears to be pretty clean but I haven't hosed it out and when I plugged in TuneECU the fan tested ok and came on when it got to 7 bars I think. It didn't get any hotter than that in the traffic.

    I didn't open the fuel tank. What are you thinking here, a blocked vent?? As soon as I got some forward speed though, even in 1st, it was fine so I'm not sure it would be that either.

    One thing I have been thinking is it does have a power commander installed which was fitted by a previous owner a few years ago and dyno'd at 121hp. I have been considering disconnecting it and trying some TuneECU maps however I am a bit reluctant bc it runs so well most of the time and I get really good fuel economy.

    Thanks for everyone's suggestions so far, I might need to take the tank off n have a good look around under there. Haven't had the bike long so I have never checked it all out.
  19. I've got a pc and 122 on the dyne lol ;). Unlikely to be the tune, but maybe you could save the existing tune (I'd love a copy of it to compare to mine too!) and put a stock tune in the pc. Maybe you could richen your mixture at idle a little, might just be starving a little at higher temp.

    Yeah the tank question is maybe the heat is causing the tip-over valve to stick - which usually isn't an issue but the breather might be clogged too. Worth checking in any case. I took my tip over valve out since they are so prone to failure, though a squirt of penetrating oil and working it a few times would suffice. Check the breather too.

    Oil in good condition? Doesn't need a flush? Oil can affect heat too because it gets heat away from bits of the engine to where the water jackets are and if any channels are blocked it can be a factor.
  20. Any luck mate?
    Still keen on a copy of ya tune if you can email it to me :p.