Help with a question about changing sprocket sizes

[sportvette]

Hi,

I would like to gear my atc 350x for more low end power. What are the stock sprocket sizes?

What sizes do I have to put on? I want to change both the front and rear. Do I increase or decrease the amount of teeth in the front? What about the rear?

Do I need a different size chain after this?

Thanks for the help in advance.

Mark.

[J.D.]

I can answer 1/2 your question. To make more low end(torque), put less teeth on front, and more on the rear.

[Tweeked]

I can only help you in one issue. By decreasing the amount of teeth in the rear--You would get less accel...but higher top em--less torque as well. By increasing it you would get greater torque and accel. but loose some on the top end. Hope this helps some

[Tweeked]

Haha, u musta posted right before I did. LOL, we answered the same thing :Beerchug .

[hrc200x]

Stock sprockets = 13/40

My guess is that you could change both sprockets so you wouldn't need a different chain. It might take a little playing around to get it right.

[tony_250r]

Here is a gear ratio chart;

[ATC350X 85]

Mark, Those 20 inch tires that are on there gave that thing a boost in low end torque. It had the original 22's on it when i got it and they just plain wore out. To get even more low end you would have to get a smaller front sprocket and a bigger rear sprocket. It might be easy to find a front one, but i looked for a smaller rear one when i put the tires on to get it back to the stock gearing and i couldnt find one anywhere. To get more low end you could put even smaller tires on the rear, but then it'd probly look stupid. Just remember more low end=less top end.

[lisnup65]

Wow !!!!!! More torque!!!??? My 350X has so much low end its frightning. I have stock gearing also with 22" tires. I have a after-market header and a 12:1 piston. The thing is a torque monster from hell.

[TimSr]

Gearing down will allow you to run at slower speeds without slipping the clutch in exchange for reducing top speed.

"Low end" is how much power a motor delivers at low RPMs.

One has nothing to do with the other.

Everyone is is correct in dropping teeth on the front or raising teeth in the back to lower the gearing. Dropping 1 tooth on the front has the same effect as adding around 3 on the back. I have never seen the logic in replacing both front and rear to reduce gearing unlesss its not practical to get there with only one. Its like digging up and moving both poles to tighten a clothsline! Whenever possible, just dropping the front is easiest, and you can remove a link from the existing chain if necessary.

[dividebyzero]

atc 350x85-james lucky carries sprocket specialists aluminum sprockets.you can go all the way down to a 34 for the rear.

[JohnR.]

This is a first, usually when I see this post it is a 350X looking for more top end. I ride mine in some technical stuff with a 13-35 gearing and a 20" tire and it doesn't need much clutching. Plus with the cam and porting I moved the power to a higher RPM anyway so it should be even worse but that motor by design makes so much torque it is still a great woods machine and it'll hang with a mostly stock 250r in a drag race.

John