Talk Composites - The Forum for Advanced Composites

Motorcycle tank project

http://www.talkcomposites.com/Topic36406.aspx

By rolandpeelen - 4/28/2020 8:35:53 AM

Hi Guys,

I've been working on an old bike recently and one of the modifications I've done is remove the front cowl entirely in favor of a simple light. Now I would like to save some weight by removing the heavy stock fuel tank.
I have looked at some plastic alternatives, but all of those require tons of modification to fit. I've been looking at some video's and I thought, perhaps it's easier to take the tank, wrap it in carbon (section by section) and then use that instead. The only problem, I haven't the singlest clue of where to start.
Some things to note;
- I don't need to keep the tank, it can be used once and then thrown out
- It needs to hold fuel, so perhaps some other resin is needed?
- It will be painted, so I'm not looking for a superclean carbon look
- It will need to be mounted to a steel bracket on the inside (can I laminate some aluminium plates in there without any issues?)
- I'd prefer not to make an inverse mold (it's ok if it's a little bit over / undersized)

My thinking was to sand the whole thing so it's smooth, use some 2 part epoxy to cover up / fill in some parts (gas cap, some other bits / bobs). Cover a section in release agent and use non pre-preg (I don't have a big enough oven) carbon to wrap it. Then take those bits, align them, and wrap with more carbon (after laminating in some tabs on the inside). Then taking some of the sections that need to be a bit thicker for strength and wrap them a couple more times. Then sand the whole thing smooth and paint it.

Will this work? And what kind of special stuff would I need to do this?

Thanks in advance for any pointers!

By Warren (Staff) - 4/28/2020 1:47:06 PM

You will need at least a 2 if not 3 part mould to get it to release properly.  Then you need to consider fuel filler cap areas, fuel tap off to the engine etc and mounting points.  Also these days, ethanol in modern fuel can play havoc with composite tanks.  Even epoxy is effected by ethanol.  You can get round it using liquid tank liners but it just complicates the process further.