Sidewinder Jerry
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A 30 series CVT. There's an adapter so you can take it from 3/4 to 5/8
4 stroke reliability and parts availability / build advice
- Thread starter Toby woodman
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Toby woodman
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do the bolt holes on the side of the engine match up?
also. with a 10 tooth sprocket the top speed would also be too fast
also. with a 10 tooth sprocket the top speed would also be too fast
Sidewinder Jerry
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Here's the thread on how to attach the CVT to a small engine.
49cc 4-Stroke 30 Series Torque Converter Build
Thought I would share my first build as I have seen some conflicting info about using a 30 series torque converter with a small engine like with this 49cc 4-stroke. I did not document this very well, as this was done over 2 months. The bike has run perfect and has about 300 miles on it. You...
motorbicycling.com
Normally, a builder would put a CVT on a larger engine such as a 212cc then a small sprocket (10t) to a larger sprocket on the rear wheel (44t). Meaning only 1 chain is needed on the left side. This would give them a very drive ratio drive system.
The other option would be to put a centrifugal clutch on the 212cc with a 10t sprocket then run it to a jackshaft with a large sprocket such as a 30t. There would also be a second smaller 10t sprocket on the jackshaft that ran to a larger sprocket on the rear wheel such as a 44t. Meaning 2 chains are needed on the left side. This would be a fixed ratio drive system.
By combining a CVT with a jackshaft you can then use a small engine such as a 49cc. Meaning you'll need 2 chains on the left side. However, you'll have a varying drive system. It'll be like starting out in a low gear and automatically moving to a high gear as you speed up. As you begin to slow down it'll automatically return to a low gear. Currently nobody has a build like this.
Toby woodman
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I'm thinking of putting an 8 tooth sprocket on a 30 series torque converter with a shaft adapter. can you see any reason why this wouldn't work
Toby woodman
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this is on a lifan 152
Sidewinder Jerry
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You have to understand reduction these engines can only be ran so low. Without enough reduction you'll destroy your engine by overloading it.
Sidewinder Jerry
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I wouldn't run the 152 below a 16\1 reduction. If you want a varying drive system. Generally whatever you add to the top end; you subtract from the bottom end.
Toby woodman
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Toby woodman
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would this not work? I'm new to four strokes
Sidewinder Jerry
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Had to get some coffee in me to wake up. The 152 isn't a very good choice of engines if you want some speed and hill climbing abilities. It'll take a total reduction of 9.28\1 on 26" wheels to do 30 mph on level ground. At only 3 horsepower this engine doesn't have a lot of power for the amount of rpm it produces. Unless you and the bike build are under a 150 lbs this isn't going to happen. A more practical speed for this engine is around 20~25 mph max.
