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Leaky gas cap 75 Superglide

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Old May 8, 2024 | 10:22 AM
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Default Leaky gas cap 75 Superglide

The gas tank on my Dad’s Superglide is rusty and crusty, and perhaps because of that even with TWO rubber washers beneath the old-style twist-lock cap it leaks bad when filled.

I bought a new cap with a longer set of retaining clips then whittled down what is probably a 1/4” CORK ring off an oil seal gasket thinking that it might seal better when it absorbs some liquid gas and swells up, but while that does seem to seat tightly it still leaks about as bad as the slimmer cap with rubber sealers. 😓

QUESTION: Has anyone successfully used a different kind of gas cap? Perhaps something like a Monza-style flip cap with a base ring that screws down over the tank opening? Such a setup wouldn’t be ‘proper’ for the bike, but I don’t like gas on the paint or, worse, dripping down onto the hot heads and am willing to try something non-standard.

Thanks a million in advance!
 
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Old May 8, 2024 | 01:11 PM
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I never fill the tanks on my Shovel all the way up, they always leak at speed. I have tried after market, exact match reproduction and factory, they all leaked. I never top off.
 
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Old May 8, 2024 | 04:05 PM
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Originally Posted by Architect
I never fill the tanks on my Shovel all the way up, they always leak at speed. I have tried after market, exact match reproduction and factory, they all leaked. I never top off.
Hrm - that’s disappointing.
 
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Old May 8, 2024 | 07:33 PM
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Are you talking about a bayonet style gas cap?
 
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Old May 9, 2024 | 05:59 AM
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Originally Posted by Imagox
Hrm - that’s disappointing.
Yes, but a reality I have come to accept. I would rather be light a half gallon then have gas in my lap when riding.

Fun with old bikes.
 
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Old May 9, 2024 | 09:38 AM
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Originally Posted by TexasScooterTrash
Are you talking about a bayonet style gas cap?
If by bayonet-style you mean it has two prongs that engage after a quarter-turn then yes. It’s not a threaded screw-in cap. The tank also doesn’t have a raised collar/lip like most Japanese bikes. I can send a photo if that’s unclear - thanks!
 
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Old May 9, 2024 | 01:05 PM
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Old May 9, 2024 | 01:35 PM
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Originally Posted by eighteight
How’s it different/better than a stock cap? Thanks!
 
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Old May 9, 2024 | 01:37 PM
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Stronger spring ? Can`t say with any certainty that it is , but for $10 , I`d try it
 
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Old May 9, 2024 | 03:39 PM
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Originally Posted by eighteight
Stronger spring ? Can`t say with any certainty that it is , but for $10 , I`d try it
Worth a shot - thanks!
 
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