Hi all,

dented the tank in my 2011 sherco yesterday

Anyone got any ideas on hows to fix it?

Ive started to look into blowing it out with high pressure air, but dont like the thought of it going bang with 100psi in it !

One interesting thing i found online was to fill it with uncooked popcorn, heat it up, and the expanding popcorn might push it out!

Not sure if thats gonna work, but seems harmless enough so am goin to give it a go tomorrow ! Ill post back the results!

Any other suggestions appreciated!

I dont have any experience of that, but heating anything in a petrol tank sounds extremely dangerous to me. depends on where and how big it is, but why not put an old inner tube in there and pump it up? Easier to get out than half a pound of mixed salt & sweet and no danger of a bigger pop than you anticipate. good luck !

I dont have any experience of that, but heating anything in a petrol tank sounds extremely dangerous to me. depends on where and how big it is, but why not put an old inner tube in there and pump it up? Easier to get out than half a pound of mixed salt & sweet and no danger of a bigger pop than you anticipate. good luck !

Ill be flushing the tank with a non solvent degreaser first, to avoid any exposions! Dont think you need much heat to set the popcorn off either. I dont believe for one second it will work, but you gotta try !

I had a road bike once that suffered implosion of the fuel tank caused by a trapped breather....as the fuel went out the tank went in....but overnight !

I got it out with a bicycle pump, pumping air into the breather tube and petrol cap sealed off. Only took a few PSI .

It needs a bit of care. Long ago two pals tried the air pressure method and ended up with a pair of wings instead of a tank.

try and fill it with water then freeze it this works with plastic tanks good look

try and fill it with water then freeze it this works with plastic tanks good look

I might try this. Thanks

The popcorn idea won't work. All that happens is there is moisture inside the kernal that expands the corn when it is suddenly released as steam when the kernal is heated. The actual pressure against the tank would only be as much as you could get pushing a popped kernal against the tank. Might as well try to bend it out with styrofoam peanuts. You would create some tiny amount of air pressure from the steam expansion but not much. If you had a form of the outside of the tank and could seal it then suction form the outside with positive pressure on the inside would work best.

Of course if the dent is just cosmetic and doesn't significantly affect safety or fuel capacity just ride it. You're only going to dent it again anyway.

I would suggest that you find a quality fellow that does paintless dent repair on cars.

For a rounded indention without a crease, you can actually stick something to it using hot glue, and pull or pop using a slide hammer.

I know how bothersome a dent on your new bike could be.....I wondered when the new bikes came out with the tank on the side how easy they would be to dent. I bet it will not be long until someone comes out with a carbon fiber or plastic tank protector.

I would be nervous about using any pressure related scheme to pop out a dent. It could work - but my concern is that you will get very little pressure on the dent - but a whole lot of pressure on the seams. I don't know how big the dent is - but if you put 2 psi of pressure in the tank and the dent is a 2 inches in area....you will get 4 pounds of pressure spread across the dent (and if it does move what will keep it from moving too far). My big concern is that if the tank is 12 inches long and 4 inches wide the 2 psi will have placed 96 pounds of pressure that will be trying to seperate the seams on the tank. (I would be surprised if you could get more than 15 or 20 psi in the tank before it explodes.....20 psi would be 960 pounds of pressure pulling at the seams of the tank if the 4x12 tank size I guessed is close to accurate). Also there is no way to control where the pressure is pushing - so it will push on everything and the weakest point of the tank is what will move. The ice method is not a good idea - the ice will probably just split the tank open.

I think the best approach is the paintless dent removal people if they can get to the dent through the filler opening. Another approach would be to cut the tank open from behind and push the dent out from behind then weld it back up, or just cut out the dent and have a patch welded on.

Edited November 15, 201015 yr by 1oldbanjo

Thanks for all your replies.

Ive actually ditched any ideas of pressure/freezing, or popcorn !

What im goin to do is cut the rear section out by grinding off the seams and accross the tank, reshape the dented section i take out, and weld it all back in again. Then dress the weld across the tank out.

I know a carbon fiber guy, so may donate my tank to him for a while to make a mould for a cover.

Might post some pics of the operation, for anyone whos in the same boat in the future !

Thanks for all your replies.

Ive actually ditched any ideas of pressure/freezing, or popcorn !

What im goin to do is cut the rear section out by grinding off the seams and accross the tank, reshape the dented section i take out, and weld it all back in again. Then dress the weld across the tank out.

I know a carbon fiber guy, so may donate my tank to him for a while to make a mould for a cover.

Might post some pics of the operation, for anyone whos in the same boat in the future !

I believe there are already some plastic CF look covers available.

Wurth sells a tool to attach to a slide hammer, use hot melt glue, remove glue with peroxide (you might want to google some info on this). Find and old tank to practice on.

https://shoponline.wurthusa.com/wurthusa/servlet/CyberVendor/category/C7465484/Catalog//