Gear ratio for scooter?

deepsnipe · #1 10-22-2008, 01:25 AM

Hi Guys. I need help setting up the chain on this scooter. I got the scooter with a 45 tooth rear sprocket and I would like to know what whats a good gear ratio for this scooter using a 43cc chainsaw motor and weighing 190 lbs? I would like it to have alot of top end power but not to weak down low. I also need to know whats the best way to connect the chain the the chainsaw? Can I get a new centrifugal clutch cover or do I got the mod mine?

**Dan** · #2 10-22-2008, 02:33 AM

Hi deep snipe, I just asked a similar question. Ocscully Did this up. Hope it helps.
Index of /ratiocalc

comfortableshoes · #3 10-22-2008, 05:58 AM

I think that if you want to use that clutch cover you will have to mod it... I"ve not used a chainsaw before but I've read that the way the teeth are on it won't work for a bike chain that the chainsaw chain is way different than bike chain...

In 1988 I had a scooter a lot like that one. It would have been way cooler motorized, as was it wasn't very fun at all. I think my father may still have the blasted thing in his barn. Last time I went to visit he still had my 1980s huffy women's road bike in that late 70's early 80s dusty blue everything was back then.

MrMike · #4 10-22-2008, 06:17 AM

here's a gear ratio calculator,look around on the page..Hope this helps.

Gearing Calculator

ocscully · #5 10-22-2008, 12:25 PM

Quote:

Originally Posted by Dan

Hi deep snipe, I just asked a similar question. Ocscully Did this up. Hope it helps.
Index of /ratiocalc

I just provided a link to the calulator above I did not write the program. Its a very good calualator though.

ocscully

deepsnipe · #6 10-22-2008, 06:21 PM

Thanks for the calulator link that will come in handy. But I need to know a good ratio to use not how to find it. What do you all think about 10:1 or 12:1? The scooter has 12 inch tires.

**Dan** · #7 10-22-2008, 09:16 PM

The calculator will help you figure that out. RPMs+ratio+wheel size= speed. It will give you options.

Ocscully, Thanks again for that. I had zero understanding of the concept. Using that I designed a really Cool (and hopefully working) gear box for 4 strokes. Will sit behind the seat tube. Took me 4 hours and was pulling my hair out. When I "got" it, it was like "Eureka!" LOL.