Gearing Question!

[stumbows]

For anyone that knows a little about gearing ratios and sprockets you may be able to provide me with some insight.

I’ve been running up until Sunday a 15/43 tooth setup on my 125cc bike.

This was extremely low and I was never using 1st I was taking off well in second and getting to 3rd quite early.

So I decided to go out and buy a new sprocket for the front which I did and increased the tooth count by one making it now 16.

Although this has made some difference it’s not very much at all. I would say that 1st is not 20% taller than it used to be when I was expecting maybe 50% at least.

So before I ask I have to say that I am going to lower the rear now and not the raise the front anymore.

So what would be the best number to drop on the rear? Would 2 teeth not be enough?

Would 4 make the difference I am looking for?

Thanks

 

[el_davo]

what size is your rear wheel?

 

[stumbows]

It's a 12inch although that information isn't too relevant and incase anyone would like to know the front is a 14"

 

[Divy]

when you take two teeth off the rear is the same as adding one tooth to th front sprocket

id suggest the 15tooth at te front and 37 or 39 on the rear

 

[mini mullisha]

1 tooth front =3 tooth rear!!
Ya prob need a smaller rear?Not sure if ya can go any bigger on front than 16?
I think if ya got 3 smaller on rear should do the job?

 

[Divy]

oh i thought 1 front = 2 rear

 

[coolmodee01]

what sort of riden you do?

i freestyle with a 15/40 rear or somthin similer i think its 39th i havern't counted it but its a bit longer for the open track keeps up with the stock experts on the power side of things

on the race track i run a 44th rear it gets me out of the corners a bit quicker
(i'm not a little bloke the power is handy)

as for motard i dont know

i think it also depends on how you ride to i ride on it or off it

have a play around see what suits you but from what your saying you will definantly need to go a smaller back and go back to the 15

 

[stumbows]

I've done a bit of research and it would seem you can only go down in 2's and i think Divy may have been right in saying 2 teeth at rear = 1 tooth on the front.

So in saying that it would seem i should go down 4 at the rear and see how i go.

Does any one think this would be going to far?

 

[Divy]

nah i dont i think it would be a good set-up but i guess the only way to know it to give it a shot

 

[stumbows]

Ok so what does everybody else run?

I'll see what's common around here and make a bit of a decision.

 

[Divy]

go for the 15-37 like you said, i just read my reply and it looks like i said no i ment to say no you aint going to far and yeah its a good set up

im using 16-37 and some times i change to 15-37 the 16front is better for me cause i ride alot of long straghts