Can anyone help me with gearing

[ned-999]

Hi I have a chopper that has a gs750 e 1982 engine in it. I'm confused because the gearing seems wrong. In 5th gear at high revs I'm doing about 45 mph !! I've checked the sprockets as follows. Front 15 teeth rear 41 teeth rear wheel 17 inch. That all looks standard to me. I can't believe someone would change the gear box. Why should they. Any ideas help would be appreciated.

[tkent02]

What's your idea of high revs?

[ned-999]

Don't have a rev counter but it's got to be 4 or 5000 by the sound of it. I can pull off in 3rd without any effort it just doesent feel correct.

[tkent02]

4 or 5,000 is just getting going. The engine needs to spin to do anything.

It starts to get powerful above about 7,000.

[ned-999]

Thanks for the reply. Il get a rev counter and find out.

[wymple]

Don't have a rev counter but it's got to be 4 or 5000 by the sound of it. I can pull off in 3rd without any effort it just doesent feel correct.

That seems wrong, it's probably been geared too radically. Maybe your clutch is slipping? Pulling away in 2nd, fine, but easily in 3rd is a bit too low. Easy fix with sprockets.

[ned-999]

I've looked at the sprocket sizes and they are 15 and 41 which is correct I think. Clutch isn't slipping. I can get bigger front sprocket 16 and 17 teeth. Would that make a difference ??