number of teeth

[semperfi1110]

quick question?
just getting into the sport and was wondering what the difference does in the number of teeth in the rear sprocket?

 

[JPIVEY]

more teeth ( 52T )increases zip at the bottom, reduces top speed, less teeth ( 48 ) less zip in the bottom, but better top speed.

Same can be accomplished by changing counter shaft gear 15T better top speed, 13T better bottom end, 15/48 = hold on tight, 13/52 = hold on tighter

 

[kaboom1371]

dropping one tooth on the counter shaft is close to adding 3 teeth to the rear. or vice versa. It's a lot cheaper to replace the counter shaft sprocket if you want to test it to see if you like it before spending the cash on a whole new set up. it will give you a better idea of what combination you want to go with.

 

[semperfi1110]

and if i drop or add teeth does that mean i need a new chain or are they one size fit all type?

 

[nikki]

and if i drop or add teeth does that mean i need a new chain or are they one size fit all type?

Unless your current chain is like new, rule of thumb is to replace your chain when you replace your sprockets. If you put a worn chain on new sprockets, you will wear our your new sprockets quickly. Same for the opposite, if you put a new chain on worn sprockets, you will also wear out the chain quickly.

Usually when you get a new chain and sprockets, the new chain is longer than what you need, and you will need to it down to fit. We use a grinder to do this, you can also use a chain break tool. Or if you use your current chain, and if you go a lot smaller on the sprocket size, you might have to cut out a link too. If you go much bigger, depending on where you are currently in the chain adjustment, you might need a new chain if your current one won't fit. Usually just one tooth won't make a different, but 2-3 teeth might.

Another way to figure out gearing is to get the ratio by dividing the rear sprocket teeth by the front sprocket teeth. So a 48 rear/13 front = 3.7 and a 52 rear/13 front = 4.0, the higher the number, the more the torque, but less top speed in each gear. And the lower the number is more top speed, but less torque. Also, you will see that a 52/14 = 3.7 and a 48/12 = 4.0, so these would be similar to a 48/13 and 52/13, etc.