sprockets/ gearing

[paco13]

Hello,
What is the stock sprocket size for 1980 GS1100E?
Sunstar, JT, Parts Unlimited list stock with 42 tooth rear, The Haynes manual list stock as 45 tooth rear. Anyone Know the correct #?
Thank You.

[rphillips]

Stock is 42, if you want you can use a stock sprocket from a Suzuki RE 5 rotary to cheat a little & still look stock, a stock sprocket from a Suzuki RE 5 is a 43 tooth & bolts right on. nobody will ever know.

[chef1366]

If you want to be quicker off the line try a bigger sprocket.
If you want better gas mileage try a smaller one.
Good thing about chain drive is you can play with your ratio.

[demark]

If you want to be quicker off the line try a bigger sprocket.
If you want better gas mileage try a smaller one.
Good thing about chain drive is you can play with your ratio.

Stock is 630 x 96, 15 teeth front, 42 teeth rear, 2.8 ratio.

Given the 1100 has more than enough power for me, I went with a 530 x 112 (?) chain, 17 front, 45 rear, 2.65 ratio.

Make for a much smoother and quieter ride. Plus, 50+ MPG doesn't hurt either.

If I had to do it again, I'd probably do a 18/48 because the sprockets would be closer to stock diameter.

[paco13]

Thanks Both for the Help. Right now I have 42 but it feels a little tall. I live/ride in an area with lots of tight twisty back roads, and many hills. Think I'll go up a couple teeth when I replace sprockets next time.

Paul

[madjack57754]

One tooth on the front equals 3 on the rear is the rule of thumb that I always use

[bradleymaynar]

I went to a 16/41 combo that got me near 50 MPG. The biggest problem I noticed was that it would tend to bog the engine on take off. What was nice, though, was cruising at 70 with the RPMs at 4k.

Currently I'm at stock (15/42), and planning on going to the 530 set-up on the next chain/sprocket change.

Brad bt

[Road_Clam]

Thanks Both for the Help. Right now I have 42 but it feels a little tall. I live/ride in an area with lots of tight twisty back roads, and many hills. Think I'll go up a couple teeth when I replace sprockets next time.

Paul

I run 16/40. MUCH better for highway cruising. My 75 mph rpm's are about 4000 rpm's. GS1100E's are geared more for straight line drag racing, than modest cruising...