TOPIC:

hey guys, the new look is great.

i have a 80 ltd 1000 w/ stock 15/33 sprockets and 16 inch rear wheel.

i'm going up to a 16 tooth drive sprocket. i do about 60 mph per 4000 rpms w/ the stock setup.
what will the 16 give me? i'm not very good at math.

thanks,

mcat:unsure:

It's a proportionality problem.
The present ratio is to 60 as the new ratio is to X

15/33/60 = 16/33/X
solve for X

1)mult both sides by 33
15/60 = 16/X

2)mult both sides by X and by 60
15X = 16*60

3)divide both sides by 15
X = 16*4 = 64

-Duck

I put this post in a different message, hope it helps you. I had too many drinks tonight to edit it for your application.

Final drive ratio.
Divide the rear sprocket tooth count by the front tooth count and you have the final drive ratio. For example: 35 / 15 = 2.33:1

If you want to change your gearing, you can calculate the impact of the change before you purchase the new sprockets.

For example; your bike cruises at 60 mph / 4,000 rpm and has a final drive ratio of 2.33:1 - if you want more acceleration, putting a 37 tooth sprocket on the back and leaving 15 on the front changes the ratio to 2.47:1 (37 / 15 = 2.47:1). Divide your cruising RPM by 2.33 and multiply by 2.47. Using the example from above, 4,000 rpm becomes 4,240 rpm at 60

with your stock setupyour gear ratio is 2.20:1(wheel speed)

if you go up to a 16 in the front you will drop you high speed rpms and loose a little on accel. a 16/33 setup wil give you 2.06:ratio. if your dead set on a 16 front and you area looking for more take off as well as a good top end gear i sugest runing a 16/40 or 16/39. a 16/40 setup will give you a 2.50:1 ratio
16/39 will give you a 2.43:1 ratio