Here's a question: If a mini bike frame (or portion of that frame) was made from something like, say, 1 1/2" tubing; could the frame then be used to actually serve as the tank? It seems filling could be accomplished by welding a "standpipe" with a bung on top. The point at which the supply was located would, no doubt, have to be "thickened" with a small plate in order to provide enough material for tapping, I suppose. Any thoughts?
Fuel tank in frame?
- Thread starter Sunnyknoll
- Start date
Wow! Thanks for that. There are things about that concept I find appealing; not the least of which is not having to purchase and mount a stand-alone fuel tank. Truth is, my initial question was prompted by some sketches I was doing for a small bike that just didn't seem to have a reasonable place for a tank.....without compromising its overall appearance, that is. Definitely going to be thinking about this.
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The Buell XB Series motorcycles used the frame as the fuel tank and the swingarm as the oil tank.
https://en.wikipedia.org/wiki/Buell_Motorcycle_Company
For a minibike frame, oval tubing would provide increased volume while keeping width reasonable. Search "oval tubing" and you will find plenty of sources. Rectangular tubing could be used, also. I would use fuel tank liner to prevent rust, if fabricating from carbon steel. I would utilize only the top tube (single or double) portion of the frame for fuel.
https://en.wikipedia.org/wiki/Buell_Motorcycle_Company
For a minibike frame, oval tubing would provide increased volume while keeping width reasonable. Search "oval tubing" and you will find plenty of sources. Rectangular tubing could be used, also. I would use fuel tank liner to prevent rust, if fabricating from carbon steel. I would utilize only the top tube (single or double) portion of the frame for fuel.
You might want to add a couple more fuel outlets front and rear and tee them together with one line running to the carb. With a long tank and no slosh plates inside, and low supply of gas, the gas will rush to the back on acceleration and leave the outlet with nothing but air...
You could also just use one center outlet and a big diameter fuel line maybe even coil it for added capacity for the carb to alleviate any fuel starve problems on drag race type passes. You might think the float bowl supply is good enough but in reality, it isn't with a high hp engine and full song from a dead dig.
JMO Danford1
You could also just use one center outlet and a big diameter fuel line maybe even coil it for added capacity for the carb to alleviate any fuel starve problems on drag race type passes. You might think the float bowl supply is good enough but in reality, it isn't with a high hp engine and full song from a dead dig.
JMO Danford1
One thought that crossed my mind was this: Wouldn't it be possible to eliminate the fuel starving problem by drilling a small hole (maybe something like 3/4") somewhere in the bottom of the frame tube and welding-on a piece of short tubing directly over that hole? This tube could be something like a few inches long? What I mean is; this short tube would hang down under the frame tube and act a sort of "vessel" for holding fuel when the bike is out of level. The bottom of this tube would have a cap welded onto it and be tapped for the fuel supply line. Seems like this might work.....especially for round tube frames. Just a thought.