Front sprocket to Rear sprocket

[Honda 250r 001]

is there a difference between changing the rear sprocket vs. front sprocket? power? torque? revs?

I heard there might be a different feel if you run 13/39 instead of 14/42?

[k265r]

what

[IcutMetl]

Come again, trucker?

[Balaz_73*00]

Changing 3 teeth in the back is equivelent to changing 1 tooth in the front.

[Honda 250r 001]

i heard somewhere that the smaller the front sprocket, the faster it revs, even if you change the rear sprocket and make it smaller to make the ratio the same.

Just wondering.

[Balaz_73*00]

Originally posted by Honda 250r 001
i heard somewhere that the smaller the front sprocket, the faster it revs, even if you change the rear sprocket and make it smaller to make the ratio the same.

Just wondering.

The smaller the front sprocket (or the larger the rear sprocket) the faster it will rev out giving you a more torquey feel (but you will lose top end). If you change both sprockets but keep the ratio the same, it will act the exact same way. A ratio is a ratio. If you want it to rev faster, go down 1 tooth in the front sprocket and that will do the trick. I did this and have had no issues on any motocross track from small technical ones to large national style ones.

[Honda 250r 001]

hmm. ok should i go with the 14 front sprocket for chain life or should i go with the 13 tooth front sprocket. then i will decide what rear to use.

[Balaz_73*00]

Drop 1 tooth in the front. It won't cause chain problems.

[Honda 250r 001]

im not goin any smaller on the front than 13. im thinkin maybe im gonna go with a 40 or 41 on the back.

[Balaz_73*00]

I agree don't go below 13t up front. If you want more torque go up 2-3 teeth in the rear sprocket. 3 is pretty standard.

[deathman53]

why would you want to go a smaller front? or larger rear. I use 14/38 and 1st and 2nd gear are pretty useless, most of the time, I'm in 3rd. Go back to stock gearing 13/38 and see how you like it. If its not good enough, what condition are the reeds, low compression top end, jetting right and maybe wrong pipe? I had a pt type 6, low-mid ported, 180 psi, 38 a/s and v-force reeds. I tried 13/39, it was useless in the woods w/ 20" tires. I went to a 14/39 and it was use full, plenty of torque and respectable top end.

[Honda 250r 001]

i think in gonna try 13/40 for starters. this is for a duner 310 with 22 inch kendas.

[voodoochassis]

i run 13/39 with 18" turf tamers and pulls like a demon on the track..

[Swiper77]

Theres is very little difference from 13-39 to 14-36 theres a tiny bit of chain drag difference if your an engineer, but you can not till a difference in the seat, guaranteed. A ratio change is noticeable .

[adamson350r]

Isn't a smaller rear sprocket for speed? If so the rear sprocket would have to be taller like a 42. I run a 14 tooth sprocket on the front and I am thinking on running a 40 tooth sprocket on the rear but I don't know who makes one. Any suggestions?

[deathman53]

the higher the number when you divide the counter shaft by the rear sprocket is the ratio which equals more speed 14/36 is .38, 13/39 is .33, 14/38 is .368. A 14/36 is alot faster than a 13/39, but the sacrifice is ability to pull it and acceleration. A 13/39 accelerates alot faster than a 14/36, but the 14/36 will start to pull on the 13/39 once it hits 4th or 5th. The 14/36 will walk away. It takes a good motor to pull some of the higher ratios also. If you are riding sugar sand a 14/36 will be a hard pull and it takes one hell of a motor, where a 13/39 would be a much easier pull.

[deathman53]

Ironman sells a variety of sprockets and they last forever(longer than some bikes). They sell up to a 43 for honda 250r. Not cheap, but if you want a sprocket to live a long time, its the only one.

http://www.dirttricks.com/ironman_quad.htm