Hello! I'm really new to mini bikes and everything. I got this one as a project for school. The guy said it was a vintage 1970s trailhorse. This one has the springs in the forks but no springs in the back. Talk about a stiff ride when your offroading. I have a few questions for some people who have been doing mini bikes for years or whoever knows anything about gearing. Anyways i had a Honda clone 6.5 hp motor that came on the bike. No governor and the bike only went about 20. I blew that motor pushing it pretty hard. I bought a harbor freight predator 212 motor and put it on my bike. This bike is super slow now. I can maybe hit 15 if im going on a really steep downhill. I want to make this thing go about 40mph. I know its really dangerous but i want something that i can go fast on when i see a cop in the desert that's marked no trespassing. My current setup right now is this: My clutch is a 3/4 bore 10tooth #420 chain. I have a jack shaft on this bike. On the jack shaft the gear that is driven by the clutch is a 20 tooth. I don't know what bore. Behind that gear is a 10 tooth sprocket that goes to the big sprocket on the back wheel. The big sprocket is 55 tooth. I did a gear ratio calculator on the internet and it said my gear ratio was 5.500. I have a 13x5.00x6 tire on the back. Does anyone know what size gears i should buy to make this thing a beast? The motor is a max of 3800 RPM. Any help is greatly appreciated.
Trail Horse Gearing??
- Thread starter trailhorse212
- Start date
- Tags gearing horse trail
with the 10t clutch driving the 20t on the jack-shaft and the 10t driving a 55t you net a 6.5 for gear reductions which should have great hill climbing capabilities but it may not give you the best top speed. If you in turn have the clutch 10t driving the 10t gear on the jack shaft and the 20t driving the 55t now you have 2.75 for gear reductions which will give you not so great hill climbing but better top speed.
