[Honda100]

Let me explain,

Oh hi, I am new here. I've lurked and read here and there for a few years but finally signed up today as I have an experiment I want to try.

I have a Honda Super Cub with a 90cc (84) motor. On hypermiling trips 25 mph "cruise" I have managed to get it up to 350 mpg. The bike is bone stock and has about 179k miles on it (so it's getting very old).

Now I'm interested in mixing a fuel that has a little more BTU and also one that would allow me to run leaner without overcooking anything. I'm toying around with the idea of mixing some petrol and diesel together but am wondering if anyone has tried that, and also if it's possible to try mixing a tiny amount of meth/water in with the petrol to create a possible detonation suppressant so I can run the bike leaner than normal. I know it's risky, but I am interested PURELY for the fun aspect of things and seeing how high I can get the mpg figure.

P.S. I know that to gain a greater efficiency out of the bike I need to mechanically change things like the compression ratio, intake manifold and ports, exhaust baffles, etc. I am looking for a "pour and play" solution. Thanks!