Motorcycle Tank Repair

In my move from Virginia to New York, I very carefully strapped my 1998 Honda Superhawk 996 onto a trailer and towed it the entire way without mishap. When I arrived in NY, a good friend of mine was helping me to unload the trailer (which had other items on it besides the motorcycle). He had a moment of mental weakness, unstrapped the bike, and hopped off of the trailer. His hop jarred the trailer just enough to send the bike off of its sidestand, resulting in it landing topside-down in the driveway. The fuel tank and much of the bodywork was damaged.

Here is a general overview of my do-it-yourself repair of the gas tank.

Note in the following photo (a bit blurry) the major dent in the top of the tank, as well as some minor additional dents. That very attractive hand belongs to yours truly, Renaissance.

Modern motorcycle tanks are constructed with a double wall... sort of like a tank within a tank. So, it is not possible to just reach a tool into the tank and push the dents back out (plus, it is pretty tricky to fit anything into the tank anyway, given the small filler opening). I elected to try pulling the dents out from the outside as much as possible.

To do this, I used a hot glue gun and a stick. I applied a dollup of hot glue to the center of the dent, and then pushed the stick into the glue. After several seconds, I would pull straight up on the stick (don't yank it... pull the dent), and usually the dent would pull out a bit. The trick is to wait the right amount of time... Wait too little time, and the glue is too hot and soft, so the stick pulls out. Wait too much time, and the glue cools and hardens too much and loses its grip on the painted surface. Anyway, wait a few more seconds after pulling, and then yank the stick... it comes right off.

After pulling, the dent is only about 10-20% as deep as it originally was. Good enough for me...

The next step is to remove the paint. I find that the best way to do this is by using a paint stripper.

Tape any areas which you would like to protect (I covered the area inside the gas filler after removing the filler door assembly).

The stripper I used was a spray-on Aircraft Stripper product purchased at the local Auto Zone. This stuff is dangerous to breathe, so use it in a very well-ventilated area! Check out the photo of the paint curling up. After waiting a few minutes, the paint just wipes off.

Here is the stripped tank. The paint stripper may leave a slight residue, so the tank must be washed thoroughly before body filler and paint can be applied. I used clean water... follow whatever directions state to do on the product.

I marked the dented areas with a Sharpie before using body filler.

The body filler was applied in thin layers, and when completed the deepest part was about an eighth of an inch thick.

Spread a layer, let it set up, shape it, let it harden, sand it down.

Repeat until it is the right height, smooth, and the feathered edge cannot be felt with your fingertips (close your eyes and feel it).

When you are done with the body filler, you are going to want to use a glazing compound to fill in minor scratches and pin holes.

OK, good enough?

Clean the tank again to remove all dust and fingerprints. I used a pre-paint spray-on product to help with this.

Prime the tank. Use an air compressor and a spray gun if you have such equipment. Rattle-cans (spray paint) works well, too. I suggest buying a trigger attachment for the spray paint if you go this route, as it allows for a better spray pattern, less drips, and far less finger fatigue. Priming the tank may take several coats.

Then, the tank is ready for a repaint. That will take several coats of paint, followed by several coats of clear, followed by several levels of wetsanding. The final finish is determined by attention to these steps. Note that your primer and your paint must be compatible.

Here is the tank in primer, prior to paint and clearcoat.