hissing gas tank

[Cha0s00100]

It's pretty much normal for the 250 Ninjas, sounds like a whale or dolphin call lol.

This is why my Blue 09 Ninja was called Shamu ;P

[Garvarg]

Yes this can happen even without running the bike. Temperature changes from night to day can be enough to cause the gas in the tank to contract and expand. There is a pressure relief valve under the gas cap, its just a small rubbery thing and when dirt, wax and stuff get it dirty it will squeal instead of working quietly. Take a can of compressed air and spray around the underside of the gas cap and this will often get rid of the problem.
This happens to my bike whenever I overfill the tank.

[djbordie]

Just noticed that my gas tank hisses (08 ninja)...now i've done a little searching around, and found that kawi's are known for it
(read somewhere that most fuel injected bikes do it)

From all I've read, the hissing is usually noticeable after a ride...or if the temperature outside is hot...
(something about heat from the engine expands the gas, building pressure in the tank)

But I haven't ridden the bike this season (broken wrist). I got a pre-season tune up about a month ago, and she's been sitting there ever since.
It was not warm at all today (btw, the bike was not in any sunlight, it was in the garage all day)

I came home after work, and went over to the bike to see how she was doing...and that's when I heard a very low hiss coming from the gas cap.

I opened and closed the gas cap...and the hissing went away...but, it came back a few moments later.
After a second time of opening and closing the cap, the hissing stopped.

Anybody, have any insight on this "non-ridden, cold temperature gas tank hissing" ?

means its soon to implode.

[kickstartt]

Attachment 28388

you drive a ninja, get used to it.

or have fun with it.

ahahhaha

[Two50noob]

There is a really quick and easy fix. Take a hole saw drill bit (any size larger the better) and drill a hole in the side of your tank...It will no longer hiss but you might might find your fuel economy suffers a bit.

[wikeke]

thanks again to all those who genuinely tried to be helpful.

[Katt]

Does it on my ninja all the time.

[Stewart]

all you kawi guys out there ...just make the hole in the gas cap a little larger than stock, problem fixed. no charge.

[Jana636]

My 09 250 would hiss and sometimes whistle. It's totally normal and kinda funny. I kind of miss that sound.