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hey guys i was looking at some stuff and i came across this gearing breakdown. i know if you looked hard enough, you could find it... but here you go!

“What is gearing down?”
“Do I need a larger or smaller front sprocket for more top speed?”
“What effects will my ATV have if I switch to smaller tires?”

I’m sure you get my point by now. Well I hope this quick overview will enlighten everyone just a tad.

Larger - front sprocket = more top speed, less acceleration
Smaller - front sprocket = more acceleration, less top speed
Larger - rear sprocket = more acceleration, less top speed
Smaller - rear sprocket = less acceleration, more top speed
Taller - rear tire = more top speed, less acceleration
Shorter - rear tire = more acceleration, less top speed
1" @ the rear tire roughly translates to 2 teeth on the rear sprocket.
2-3 teeth on the rear sprocket roughly translates to 1 tooth on the front sprocket
"Taller" ratios mean more top speed, less acceleration, smaller numerically.
"Shorter" ratios mean less top speed, more acceleration, larger numerically.

To obtain a gear ratio, divide the number of teeth on your rear sprocket by the number of teeth on your front. For example, 13-tooth front and 40-tooth rear.

40 divided by 13 = 3.07

If you had a 11 front and 37 rear that = 3.36

If you had 3.36 and you went to 3.07 that would be considered moving to a "taller" gear, because you're going to achieve a higher top speed with it.

If you had 3.07 and went to 3.36 that would be considered moving to a "shorter" gear, because you'll be acceleration more and achieving less top speed than before.

Keep in mind, depending on engine power rating, you will NOT be able to rev out last gear in every ratio! If you have a 14 tooth front sprocket and 30-tooth rear sprocket on a stock 250cc quad, you can hang that idea out to dry, because it’ll never be able to pull it with 100% efficiency.
 

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Yea! it's a great write up on gearing & ratios...!!!

There's this one also from SuperWes..

SuperWes

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Join Date: Dec 2009
Location: Nebraska
Posts: 346
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Looking at the sprocket gear ratios:

14 / 38 stock ratio is 2.71
15 / 38 is what a lot of people change to at 2.53
15 / 39 is at 2.60 is what nkeen07 preferred, but you have to add 2 links
14 / 36 is at 2.57 is what I'm happy with right now with the big three and KX intake cam. I didn't have to take off any links and it looks like I still have plenty of room left over to adjust more chain slack later on if needed. I usually run 20 inch rear tires for trails. I also have 18 inch tires for the track, but I haven't tried them with the 14/36 ratio yet.
 

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I have a gear ratio system on my email. I can try to post lets you put in different sprockets and shows you what gear you would be running.
 

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I personally like a 15 / 36 =2.40 ratio with 18" tires. Its a little tall on take off but anything else seams to spin too much. Whith all that wheel spin my quad felt weak but with the taller gears it feels much stronger and more predictable.
 

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Heck yea good find Dust. I mean I can do the math and all but that tells me where I am and where I want to be. Plus it tells me what chain length should be.
 

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Do I need to add or remove links from stock with one tooth in the front up or down?
 

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Not usually. But it just depends on how stretched or new your chain is.
 

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Discussion Starter #9
Just imagine if the Kawie had a 6th gear... Problem solved! Haha.
 

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Just imagine if the Kawie had a 6th gear... Problem solved! Haha.
Yes, that is what I used to think it needed, and it does... or a wider ratio trans.

My thinking back then is woods guys could bring the gearing DOWN to make 6th like 5th and open area guys would love the 6th gear. But I figured out I couldn't hold on to it long when I tried lowering the gearing a lot.

I have been meaning to play around with it while I am running 21" rears... but it kinda helps to have a clutch and brakes first... lol... so maybe when I get those things fixed.
 

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As for calculators, I found one I used that told me everything once I found the tranny ratios for the gears.

If I can ever find time I will dig up what info I found and code a little app you guys can load and use. Finding the info again and the time will be the issue.
 

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As for calculators, I found one I used that told me everything once I found the tranny ratios for the gears.

If I can ever find time I will dig up what info I found and code a little app you guys can load and use. Finding the info again and the time will be the issue.
Duster! Did you forget about this one? Or you're still looking for it? Hehe :p
 

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Yes I sure did forget. Need to add it to the rainy day list.
 
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