Don't Overtighten Gas Tanks

[HT2005]

A few weeks ago I was riding my bike on a route that was about 10 miles long. About halfway through, I noticed the smell of gasoline. So, I looked down at the carburetor and couldn't see anything wrong. No gas was coming out of the vent cap on the tank either. I continued to notice the smell at low speeds but didn't think too much of it because I couldn't see anything.

Once I got home, I noticed something dripping on the driveway from my bike. As it turns out, premixed fuel had been dripping out from the studs on the underside of the tank. It was dripping at a rate of two drops per second. I quickly had to get a metal dish to contain the gas. It was a big mess because the whole underside of the tank was soaked along with the whole downtube and CDI. On top of that, gas was dripping right onto the hot cylinder head!

My brother tried to braze the studs, but he ran out of oxygen. I just recently realized why this incident happened. It's because I overtightened the studs to the bike tube. The studs were bent inward. This caused stress on the underside of the tank, which caused a crack to develop around the stud. Basically, the stud bent and tore the metal that it was attached to.

The lesson I learned here is to only tighten the studs enough so the gas tank can't easily move or flip over. I've installed a new tank with this in mind and haven't had any problems so far.

 

[Kevlarr]

Good thing to do when installing a tank is put some good double sided foam tape between it and the frame to "stick" it in place before your tighten the brackets.

 

[Junster]

I agree Kevlarr, I also had to braze my tank studs. The sticky foam tape holds the tank well with very little tension on the tank studs.

 

[noco]

i left mine aliittle loose and good thing i was about a mile from home when i noticed air in the fuel line... i was able to tip the tank abit and it got me home...lesson learned either keep the tank adjustable or check the gas allittle more often..

 

[Deadend]

if you're in pinch and you dont have foam tape, a bit of old tubing (bicycle tire air tube) works as well

 

[scooterhoot]

BGF sent me 2 rubber strips for the motor mounts, didn't use them. tank kept on moving, tried a self tapping screw though the bottom mount, screw sheered. Put the rubber pad under the tank mounts and have had 900 mi with out any problems.

 

[2door]

Electricians use a something called 'splicing tape'. It is a thick, tacky and stretchy rubber product that comes on a roll like electrical tape. It can be wrapped around the top bar before mounting the tank. It holds well. It can also be used to keep things like horns, lights,bells, anything that clamps to your handlebars from loosening and rotating. It's not a standard hardware store item but electrical supply houses carry it or maybe you know an electrician who would part with a roll. Bicycle shops sell a similiar product but much more expensive.
Tom

 

[noco]

Electricians use a something called 'splicing tape'. It is a thick, tacky and stretchy rubber product that comes on a roll like electrical tape. It can be wrapped around the top bar before mounting the tank. It holds well. It can also be used to keep things like horns, lights,bells, anything that clamps to your handlebars from loosening and rotating. It's not a standard hardware store item but electrical supply houses carry it or maybe you know an electrician who would part with a roll. Bicycle shops sell a similiar product but much more expensive.
Tom

is this the same stuff as ive always called 5KVA tape??? why would home depot or anything else sell 5000V tape???

 

[Zebo]

Mounting my tank on my Huffy, glad i found these tips. I got mine used and one bolt on the tank is bent, I hope it does not leak.

Thanks

 

[SoFresh]

What would be a quick easy fix to stop the leak for when this does happen?

 

[FileStyle]

there isnt a quick and easy fix! drain your tank and pull it off- braze or weld after tank has been cleared or replace with a plastic tank.

 

[WildAlaskan]

heres what i do with my tanks first i cut a old tube black tape it to the frame i completly cover the innertube with tape i then screw several nuts on the studs before mounting bracket so i can get a tight fit with out bending studs i like to be able to twist my tank in case i have to load it sideways in a car or truck with out fuel flowing everywhere i simlpy turn the tank and lossen the carb and turn it too that keeps the fuel from flooding

 

[Allen_Wrench]

What would be a quick easy fix to stop the leak for when this does happen?

I dunno, "Dubble Bubble" bubble gum? You could keep some in your pocket for emergencies, it never goes bad - just gets really hard after a while.

You did ask for quick & easy. That's all I got. Since they're pretty cheap, I'd just buy a new tank with the next paycheck. I get nervous about brazing anything that had gas in it. It scares me, but that's just me.

P.S.: I'm kidding about the bubblegum, for pity's sake don't do that. I truly have no idea what will happen.

 

[scotto-]

there isnt a quick and easy fix! drain your tank and pull it off- braze or weld after tank has been cleared or replace with a plastic tank.

I've had the same thing happen, as well as having snapped one of the studs from over tightening a nut on one with screwed-up threads. To fix the crack without welding or brazing, drain the tank thoroughly and dry it out.....compressed air works well for this. Wire brush the crack on the outside of the tank to bare metal. Mix a small amount of quick setting 2-part epoxy and apply it to the crack, making sure to fill the crack by applying it with pressure with a popsicle stick or similar. Let it set-up and cure overnight and your good to go the next day. The very first one I repaired over a year ago today is still holding gas and hasn't leaked yet.

And just curious.....where can you get a plastic replacement tank? I've yet to see one outside of an old motorcycle tank.

 

[kipharley]

I put a strip of 1" wide Velcro on the tank and frame.
Then I cut 4 pieces of 1/4" gas line 3/4" long and slide one on each stud.
Then I assy the whole thing.Using a flat washer,lock washer,nyloc nut.Kip;
[email protected]

 

[corgi1]

do leave the gas cap off when brazing,even if you washed it out

 

[freewheeling frank]

i have brazed em with silver solder and a propane torch make sure tank is washed good and metal is super clean

 

[motorhead419]

Mounting my tank on my Huffy, glad i found these tips. I got mine used and one bolt on the tank is bent, I hope it does not leak.

Thanks

Here's what I do: I just use the front mount. Your frame is curved and you put undue stress on your tank if you tighten both mounts. Put a piece of thin rubber between your frame and the tank also.

 

[kipharley]

Here's what I do: I just use the front mount. Your frame is curved and you put undue stress on your tank if you tighten both mounts. Put a piece of thin rubber between your frame and the tank also.

I would think using only your front mount would make your tank flap like Superman's cape going WOT expecially with a chunk of rubber between the tank and frame! Kip.
[email protected]

 

[motorhead419]

You use a real thin piece of rubber..My bike does 40+ mph and the tank has never moved. See you in the slow lane.