Clogged fuel tank air vent !


.020 Over
Mar 16, 2007
After having spent lots of meditations,PC III finetunings, disassemblies followed by reassemblies, speculations and suiciding thoughts....
My Triumph dealer in Frederick (Maryland) found the cause of my disappointment... A clogged fuel tank air vent ! The symptoms are a kind of surging engine when riding at constant low RPM (1500-2500) with a stable idle and normal accelerations!
But the easiest thing to notice, if you know that's NOT normal :mad:, is that when you open your fuel tank you hear an important air succion.
I never knew it wasn't normal since I bought the bike with 5000 miles on it and got this effect from start.
By the way, some cars have that on purpose, to reduce the risk of fuel fumes explosion by creating a depression in the fuel tank. But not a ROCKET!!!
The solution has been to remove the oneway valve behind the left cover and now it runs like a charme.:bch:
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Great news

Pascal, glad to hear that your problem got solved. Now you can really enjoy your ride. Just out of curiousity how much did all that dealer troubleshooting cost you?
19 dtg!
The total came to $150 for the problem solving, throttle bodies synchronization, new tune and front tire change (tire not included of course, I bought it earlier on E-bay for $135).
I really expected more because I spent already a lot of time to resolve it myself, without success...
By the way How is Kabul doing?? I flew about 30 missions to KAIA between 2002 and 2005. I suppose you drive your bike in Florida instead !!!
Best greetings.
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