Leaky Gas Cap Woes

[kb0nly]

I went through this last spring with my 200es. The first thing I did was buy the $7 oem gasket but that didn't do it. I used a pair of channel locks and bent the rim up a little evenly all the way around... It still leaked. I had my buddy try bending the rim... still leaked. I got so sick of having gas dumping in my crotch I gave it one more shot and got it. Never leaked again. Just gotta keep trying till you get it.
I think maybe vacuum suck the rim in over the years?

Bending it up will make it looser and leak more... Yes you can bend them up enough until it doesnt leak but the cap is then only sealed on a small amount of the surface of the rim. I know this sounds opposite of what it should but the tabs of the cap go under the rim and are like a ramp, so as you turn the cap it pulls the cap down tight to make the seal. By bending the edge up you actually loosen the caps contact with the whole surface area. You want to bend the inner lip of the gas tank down/inward so that it pulls the cap down tighter onto the opening of the tank.

It took me a summer to figure this out on my 200ES... LOL... I tried new rubber gaskets and a new cap, still didn't seal, then i realized the physics involved and bent it the other way and the cap got crazy tight. Mine is so tightly sealed that it sounds like a gas jug that sat in the sun all day when you open it, it builds pressure as the gas expands. The air valve is definitely needed on mine... LOL

[Thorpe]

Maybe not, but if you turn them inside out you can use them twice

Ummmm.....????? We still talking about gas caps here??

[El Camexican]

Ummmm.....????? We still talking about gas caps here??

Everyone else was, but I know you better than that

[kebby28]

Bending it up will make it looser and leak more... Yes you can bend them up enough until it doesnt leak but the cap is then only sealed on a small amount of the surface of the rim. I know this sounds opposite of what it should but the tabs of the cap go under the rim and are like a ramp, so as you turn the cap it pulls the cap down tight to make the seal. By bending the edge up you actually loosen the caps contact with the whole surface area. You want to bend the inner lip of the gas tank down/inward so that it pulls the cap down tighter onto the opening of the tank.

It took me a summer to figure this out on my 200ES... LOL... I tried new rubber gaskets and a new cap, still didn't seal, then i realized the physics involved and bent it the other way and the cap got crazy tight. Mine is so tightly sealed that it sounds like a gas jug that sat in the sun all day when you open it, it builds pressure as the gas expands. The air valve is definitely needed on mine... LOL

Yes, your absolutely right. I think when I bent it up it leaked even worse. I think like you were saying I kinda bent it down on an angle to get it to finally seat. I like what you were saying about the tabs. I didn't think they would bend being stubby and on a spring.

[kb0nly]

The tabs will bend a bit, but not much. The problem is the tank lip wears a groove in them and then doing anything with the tab won't do any good. My ES was dousing me with gas when i first got it. Not fun when your buzzing along full throttle then realize your getting wet! LOL

[Ghostv2]

I've heard that brake fluid softens rubber, but his gaskets are shot. If anything a chemical dip would make them fall apart.

On the topic of tanks I think Yamaha deserves a big for the plastic tanks they used on their YTM's The cross under tube, super strong plastic and cap on mine are still like new in every aspect. Honda may have had it over them in a lot of areas, but not with their metal fuel tanks.

The YTM's tanks are easy to work with and will last pretty much forever but I like the Hondas better. I like the big metal tanks, when I was a kid it reminded me of a motorcycle. Pretty much is the same thing. It's just part of the charm I guess. It just comes down to how you take care of them. You can't get the same look and finish on a plastic tank. Maybe it's just me.

[El Camexican]

The YTM's tanks are easy to work with and will last pretty much forever but I like the Hondas better. I like the big metal tanks, when I was a kid it reminded me of a motorcycle. Pretty much is the same thing. It's just part of the charm I guess. It just comes down to how you take care of them. You can't get the same look and finish on a plastic tank. Maybe it's just me.

Very true. I loved the metal tank on my 79 YZ80. It always looked new compared to the plastic models and I don't like plastic on street bikes these days, but after 30 years so many metal tanks have rusted out or are dented all to heck. My YTM is what I plan to use as a daily driver should there be an apocalyptic event, so I like the reliability of that set-up. The last thing I need is a leaky tank when the zombies are chasing me!

[JustEnough]

http://dratv.stores.yahoo.net/gcapga3.html

[kb0nly]

http://dratv.stores.yahoo.net/gcapga3.html

Thats where i got my 200ES gasket as well... Its just the tiniest bit thicker if you compare it to a brand new OEM gasket. Good quality gasket.

If the zombies come i wouldn't want to be fully exposed on a trike... But funny anyway! LOL

[Ghostv2]

Well i fixed the rim and tabs and what do you know, seals nice and tight. I want to thank everyone for helping, hopefully this helps someone else in the future too. No i did not need to get a new gasket, but i probably will eventually so its 100%. Only problem i encountered is when you bend up the rim you need to bend the inside back in so your cap will go in.

[fabiodriven]

No i did not need to get a new gasket,

I beg to differ.

[rg97]

Buy two new gaskets and call it a day. Simple as that

[Ghostv2]

Buy two new gaskets and call it a day. Simple as that

I'll keep it short and sweet, I'm a broke 20 year old kid. Since my surgery in September I have not been able to find a job. I'm not even suppose to be working yet. I do not qualify for disability, I can't go on unemployment, I'm broke. $4 may not be a lot, but it's more than I have to my name. So as soon as I can, I will. But right now I'm working with what I got. And if it works, than it is good enough for me.
Here what my back looks like.

I'm sure you understand where I'm at with this. Recovery is 6 months-1 year. Without assistance, my bank ran low fast.

[fabiodriven]

I feel ya man. Life's been kicking a lot of us in the yam bag lately.

[Dirtcrasher]

WOW!! Ghostv2, I'm sorry about your back, man is that bad!!

Try to enjoy any pain free riding moments because as you age, unfortunately that's gonna hurt.

My doctor told me when I was 30 that I had allot of arthritis in my joints. Some mornings (now 13 yrs later) I walk like Frankenstein until I loosen up a bit and no on the shelf meds help. I can only see it getting worse.

I wondered why this thread was 2 pages and I completely understand your situation now. That was some major back surgery there!! Your probably an inch taller now. I hope you can enjoy some pain free years.......