Is it better to have a smaller sprocket on a BMX bike?

Answer 1

First you need to be clear about what you're talking about.

In regularBike-speak,sprockets go at the rear, andchainrings/chainwheelsgo at thefront.

In BMX-speak, a sprocket goes at the front, and a driver goes at the rear.

If you're speaking BMX, the most obvious difference is the size, the tooth count.

For the same size driver, a bigger sprocket will make the bike slower off the start, but give it a higher top speed.

For the same size driver, a smaller sprocket will make the bike quicker off the start, but give it a lower top speed.

If you change the driver to match, start and top speed will remain the same, even with a smaller/bigger sprocket.

A small sprocket will increase the ground clearance. Better if you're riding ramps as there's less risk of the sprocket/chain hitting the lip as you drop in.

If you're not riding ramps, well, a smaller sprocket is still lighter, which is a kinda-sorta advantage. The downside is that the smaller they get, the faster they wear. And the chain wears too.

Changing to a smaller sprocket on the rear will make your bike heavier to pedal. If you're strong enough to keep cranking at the same speed as before, then your bike will be faster.

Answer 2

The smaller the sprocket, the lighter the sprocket and the shorter the chain. The shorter the chain, the lighter the chain. Just remember to reduce your rear gear when you use a smaller front chainring or you're going to be spinning like mad. For example: Typical set up is 44 in the front and 16 in the back. If you put a 38 tooth chainring in the front, make sure to reduce the rear sprocket to a 14. Essentially, you take the number of teeth up front and divide by the rear. Simple. Ideal BMX gear ratio is 2.75, but different people have different preferences.

Answer 3

First you need to be clear about what you're talking about.

In regular Bike-speak, sprockets go at the rear, and chainrings/chainwheels go at the front.

In BMX-speak, a sprocket goes at the front, and a driver goes at the rear.

If you're speaking BMX, the most obvious difference is the size, the tooth count.

For the same size driver, a bigger sprocket will make the bike slower off the start, but give it a higher top speed.

For the same size driver, a smaller sprocket will make the bike quicker off the start, but give it a lower top speed.

If you change the driver to match, start and top speed will remain the same, even with a smaller/bigger sprocket.

A small sprocket will increase the ground clearance. Better if you're riding ramps as there's less risk of the sprocket/chain hitting the lip as you drop in.

If you're not riding ramps, well, a smaller sprocket is still lighter, which is a kinda-sorta advantage. The downside is that the smaller they get, the faster they wear. And the chain wears too.