View Single Post
Old 04-18-2012, 08:10 PM
5-7HEAVEN 5-7HEAVEN is offline
Motorized Bicycle Elite Member
Join Date: Aug 2008
Posts: 1,912
Default Re: OCC Schwinn 4hp issues NEED HELP

The cheapest fix:

Keep the 3" crank pulley. Replace 2" jackshaft pulley with a 6" pulley.

6"/3" = 2:1 ratio.

Replace 20t jackshaft pulley with a 10t pulley. Keep your 36t or whatever rear sprocket.

36t/10t = 3.6:1 ratio.

2:1 x 3.6:1 = 7.2:1 gear ratio.

Your bike should move well.

Unsure at what rpm that the jackshaft clutch will engage.

The simplest fix:

Replace 3" crank pulley with Maxi Torq clutch w/10t sprocket.

Replace 2" pulley and clutch with 20t sprocket.

20t/10t = 2:1.

Install 10t on right-side jackshaft; keep 36t rear sprocket.

36t/10t = 3.6:1

2:1 x 3.6:1 = 7.2:1

No jackshaft clutch to worry about.

Bike will move quickly.
Reply With Quote