What does changing the sprocket do?

[smokedvw]

What is the difference between stock, 1 down and 1 up like the higher what happens and the lower what happens?

[CrotchetyRocket]

M'kay...It's like this: If you add teeth to the rear you increase the leverage that gear has and improve acceleration, like putting 3.73s in your musclecar over 2.73s.

Conversely, dropping teeth on the rear will, lower rpm in gears, slow the bike's acceleration somewhat, make it more relaxed on the highway and possibly, increase top speed.

It's about the RATIO (Warning! Grade 7 math content ahead! )
betweent the front and rear sprockets. Let's just pick two ratios, 1:3 and 1:5. Which is going to have greater muscle power and leverage? 1:5. The same applies to bike sprockets. The bigger the difference small (front) to big (rear) the greater the jump in leverage, thus acceleration.

Something else to keep in mind is that changes to this will screw up your speedo's accuracy (if that word can be applied at all to bike instruments ) so, you'l need to recalibrate it, if you care. This will cost money, i.e. buying a yellow box or something like it.

Crotch

[CoolDaddyGroove]

Just imagine how the gears on a mountain bike work. Different sized sprockets require for different amount of effort from your legs.

[TeeTee]

I think I see an Articles post coming.

Lots of folks asking this question all the time.

CR forgot to mention a couple of things. First, it's common to go down a tooth or two on the front because it can be done at any time and still use the original chain. It just makes it so you need to run the rear axle back in it's adjustment range slightly. $25 and a bit of time and you're off. But forcing the chain around a smaller front sprocket leads to slightly faster chain and sprocket wear (less teeth to share the load). The preferred way though is to change the gearing at new chain and sprocket replacement time. That way you stay with stock at the front sprocket and go larger on the rear. The new chain is then cut a few links longer to fit the longer path.

Generally speaking with the ratios we use 1 down on the front is roughly equal to about 2 or 3 up on the rear.

[CrotchetyRocket]

Nyah, I didn't "forget", anything I was simply limiting the "information overload" for lesson one

Now he's going to be running around holding his head and screaming incoherently. Nice work, TeeTee

Crotch

[smokedvw]

Ok so 1 down in the front is like 2 to 3 up in the rear. Therefore it would have alot more acceleration compared to top speed?

Also how much is it to recalibrate, cause I hate driving my brothers mustang with 3.73's cause even though it is recalibrated there is no speedo that can acurately tell you your speed.

[J1k]

heres a link with all the ratio's for gearing.

http://www.afamusa.com/gear-ratio.html

[TeeTee]

Originally posted by CrotchetyRocket
Nyah, I didn't "forget", anything I was simply limiting the "information overload" for lesson one

Now he's going to be running around holding his head and screaming incoherently. Nice work, TeeTee

Crotch

I aim to confus..... er..... please.....

[rocki8888]

i was wondering bout this sprocket issue too .. thanx for the info guys

[RedDragoN]

O.K. my chain and sprocket are almost done, I am going to replace with 1-2 up in the rear. This will affect my speedo in which direction (show slower or faster), what about the odometer.

[CrotchetyRocket]

It'll make both read higher than you actual speed or mileage, something they do already anyway.

Crotch

[TeeTee]

Originally posted by CrotchetyRocket
It'll make both read higher than you actual speed or mileage, something they do already anyway.

Crotch

But now it'll be worse by far. One tooth isn't worth the effort. 2 is better but most folks that figure on doing this make it 3 so they feel the difference.

You can either spend a couple of hundred on a Yellow Box or $25 on the right Cateye bicycle speedo to act as a second "true" display. You'll get a whole lotta extra feature like trip distance, max and average speeds and a CLOCK.....

Just be sure you're quoting the correct display with the nice officer asks you how fast you were going....

[Scheme]

Dropping a tooth will make you a stunna...at least that's what it said on the packaging...w00t