1991 cb250 Nighthawk Rear Sprocket Change?

Question

I am going to change the stock 30t rear sprocket to either a 32t or 33t. I would like the bike to achieve 80 or a little more rather than 75 in real life circumstances. Hopefully, increasing sprocket size will also make the bike cruise smoother at 60-65. I realize increasing size will lower my acceleration, but I am not sure how much. Just please offer whatever advice you can on which I should choose. Basically, I am not sure how much difference there will be between a couple teeth. Thanks.

Answer 1

Increasing your rear sprocket size is going to do the OPPOSITE of what you think it's going to do (from what I'm reading of your question).

Increasing your FRONT (countersprocket) will reduce your engine RPM on the highway and give you better cruise speed.  Increasing your REAR sprocket will give you better acceleration but will INCREASE your engine RPM at speed and probably DECREASE your cruise speed to more like 70 mph.  You'll just tend to reach that speed quicker.

There is nothing free in physics.

Answer 2

It's NOT worth playing with these parameters on such a small bike. The compromise would not be a good one. Just forget about it.

Buy a bigger bike