If you are losing power on the hills and you have a tuned pipe, it's tuned wrong. I believe the solution is to lengthen the header pipe. Try getting some high temp silicone tubing from a hobby shop- they make it in a lot of sizes, some of the model engines are WAY bigger than these bike engines.

I have a tiny little Tanaka engine, but no tuned pipe. I can stay at around 15-18 mph on a hill, unless it's a really steep hill.

Oh yeah, WELCOME!

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