Triumphrat

screamingearth

My 1999 Legend TT is new to me. On arrival back in my garage after a short 3 mile ride home from work, with the engine off, there is a faint whistling noise. When I remove the gas/petrol cap there is quite a vacuum in the tank. Is this normal?

WoodsieIII

There is a tipover valve located at the left hand side rear of the fuel tank. It is a couple of inches down along a hose. check that the hose isnt kinked, and that the valve is vertical.
This is quite commonly the problem. Have you had any fuel starvation issues?

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I believe there is no such thing as accidents. When I ride I must leave enough room for others stupid mistakes, added to that is enough room to make my own.

screamingearth

Yes - I have been trying to solve a missing/hesitation problem.

WoodsieIII

Take the hose off the tank with the valve attached, hold it so the valve is vertical and blow through it from the long end of the hose.If you cant blow through it you have trouble, it will have some resistance, but should allow a small amount of air through. If that doesnt work blow from the other end to make sure it isnt installed upside down.

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I believe there is no such thing as accidents. When I ride I must leave enough room for others stupid mistakes, added to that is enough room to make my own.

MickMaguire

also check the poppet valve in the middle of the gas cap - little white round disc right in the middle it should be free to let air in - suck on it to see if it is blocked if it is just poke it until it works.

It is most likely the tipover valve - check the hose for kinks and make sure the valve sits vertically.

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Mick...

Just remember; an awful lot of the free advice you will get on forums is worth exactly what you paid for it. There will always be somebody trying to convince you to do something really stupid, just because they did it or want to do it.

screamingearth

Yep - the tip-over valve was horizontal, so I re-threaded the breather tube so it hangs vertically and there is no more vacuum. Thanks for the pointers.

jukka_kanerva

I had the same problem and took off this valve.
What is function for that?
I thought it was paint flakes/jelly problem.

WoodsieIII

The valve is to stop fuel spilling on the road in the case of an incident. It actually works too.

__________________
I believe there is no such thing as accidents. When I ride I must leave enough room for others stupid mistakes, added to that is enough room to make my own.

MickMaguire

Yup if your bike ends up horizontal then you will have the equivalent of a 1/4" hole in your tank letting gas flood out if you don't have the valve fitted. What I have never understood is why they don't more securely attach it and its hoses as it tends to fall off and get lost. Cable ties can help here.

Spilled gasoline after bike accidents was actually cited in the Hurt report.

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Mick...

Just remember; an awful lot of the free advice you will get on forums is worth exactly what you paid for it. There will always be somebody trying to convince you to do something really stupid, just because they did it or want to do it.

spillsoup

I too have a slight whine noise coming from my gas tank.

I think I have a hesitation problem, but I am not sure. When accelerating, my bike sounds like it is firing two cylinders and is sluggish. Opening the throttle more causes the bike to sound and accelerate like it is running on all cylinders. Is this characteristic of a problem with the tipover valve?

Thanks!