If you shake the bike tank around when its hot does it hiss from out under the fuel cap? Does the fuel cap let a rush of air in when you open it?
I had a bike do this and it was the tank vacuuming down. It did it mostly on sustained climbing or high speed, and particularly so in cold weather. We modified the filler so it vented slightly. Aparrently this is not a legal mod in the US. Lucky I aint in the US.
Steve
"I am a licenced motorcycle instructor, I agree with dangerousbastard, no point in repeating what he said."
"read what Steve says. He's right."
"What Steve said pretty much summed it up."
"I did axactly as you said and it worked...!!"
"Wow, Great advise there DB."
WTB: Hyosung bikes or going or not.
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