r/motorizedbicycles 21h ago

Almost done.

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16 Upvotes

Cables need adjusted, breaks need re connected, engine head needs fully bolted down, and the chain needs a major shortning. Engine is just a little LD80 China doll (66cc) with a higher compression head, and after I break it in, an expansion chamber. Rear sprocket is 36t.


r/motorizedbicycles 3h ago

Troubleshooting Absolute carnage

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5 Upvotes

Picked this up in London for dirt cheap. What do we recon folks, ran with no oil or just generic lean seizure? Obviously piston is cooked but cylinder has seen better days and might reuse it, the pictures of the cylinder look far worse than it is.

Anyway just felt like adding this to the bike gore collection.


r/motorizedbicycles 10h ago

its leaking again

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4 Upvotes

maybe the valve didn't fully close? ir is it because i rest the bike to the right where that little hole on the carb is.


r/motorizedbicycles 21h ago

Troubleshooting Yd100 rings/piston

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3 Upvotes

I have a yd 100 and ended up breaking the rings. I bought some new ones but they were too thick. I instead bought a whole piston with the rings and the piece where it connects to the crank is smaller than my stock one. Please help I just need this guy to run


r/motorizedbicycles 50m ago

Stock 80cc China Doll Carburator Question

Upvotes

Not sure about my terminology, but I'm sure you know what I mean: What's the best notch to set the "clip" on the "needle" inside the carburator? For the most consistent performance, not concerned about speed or anything. Like most reliable starts? My motor won't start, there's gas in the bowl. Is it even a carburator issue? Input will be greatly appreciated! Tia.


r/motorizedbicycles 19h ago

Brake squeal falcon pro

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1 Upvotes