[Motor7]

I am trying to grasp the ratio's and their effects...bear with me. When I removed the set up on the bike I found it to be a 16/48. I replaced it with a 15/47. The gear ratio for the 16/48 is a 3, the ratio for the 15/47 is a 3.13.....so did I lose or gain low end torque?

 

[greywolf]

You have more grunt now.

 

[Dark Angel]

You gained a little rear wheel torque at the expense of higher revs at highway speeds.
Changing the sprockets doesn't change the torque characteristics of the motor, just the mechanical advantage between the output shaft and rear wheel.

A 1:3 ratio means for every turn of the rear sprocket your front will turn 3 times. A 1:3.13 ratio means more front sprocket turns at the same road speed, giving you higher revs but slightly better torque at the rear wheel at any given engine speed.

 

[Motor7]

Thanks GW...I was off in googleland and found this:

Gearing Commander: Motorcycle Speed, RPM, Chain & Sprockets Calculator

Looks like I gained a wee bit...not sure if it is enough for these steep hills here. I'll ride it for a while and might see if I might need a 14T front

 

[Motor7]

DA, it might be about right....I found with the 16/48 I only hit 6th gear a few times on my last trip...no "innnn-er-state".

 

[PTRider]

Easy to change the front sprocket, and one tooth makes a noticeable difference. The chain can be adjusted for a one tooth change. It takes about three teeth on the rear to get about the same change as one tooth on the front, and it is likely that the chain would have to lengthened or shortened after a three tooth change.