Author Topic: Gearing Changes  (Read 4333 times)

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Offline Big Yac

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Gearing Changes
« on: May 01, 2011, 04:30:57 AM »
I am needing some new sprockets and a chain.  I am going with a Tsubaki O-ring chain and Renthal sprockets.  I will most likely go with the stock gearing as its worked fine for me.  I wonder though, what are the effects of changing sprocket sizes either larger or smaller on the rear and how many teeth would I have to go to notice a difference, would 1 tooth change how the power feels or would I need to go like 3 teeth before noticing?  I can tell you I will not go smaller on the back because I do alot of woods riding, so if I go larger would it let me use the lower gears more or what?  I've never changed gearing on any of my bikes.  Thanks.

Offline Rider1958

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Re: Gearing Changes
« Reply #1 on: May 05, 2011, 12:23:24 AM »
Over the years (and this is just my personal opinion) I've found that the absolute best (and first) mod for tight trails is to lower the gearing - the lower the better for me. It seems I can then use the throttle to control tough trails and uphills instead of the clutch, which when slipping heats the engine up greatly - not good when moving slowly.
I always put a larger rear sprocket on AND a smaller front, that way you have ranges of lower gearing available to you with a simple front sprocket change.
When trail riding using the small front, I carry a larger-than-stock front sprocket with me, along with a few tools to change it, so I can hit the road to get home if I need to.
You'll need to watch chain length if using this method - get a long enough chain to be able to use the range of sprockets - you can cut links off but cannot add 'em.....

Offline mx_dad

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Re: Gearing Changes
« Reply #2 on: May 24, 2011, 06:52:56 PM »
There are several ways to look at this. One way is to say I can go larger in the rear and now turn that corner and climb that hill in 3rd where before I had to use 2nd. OR, you can go smaller on the rear and turn that corner and climb the hill in 2nd, but go faster than you did before.

In general though, I'd agree with big Yac, lower the ratio for woods riding. If you go smaller on the front, make sure that the angle the chain leaves the front plastic guide isn't increased so much that it causes pre-mature wear. Same with going larger on the rear. Make sure that the larger sprocket doesn't put to much down force on the rear chain guide causing pre-mature wear. Most bigger bikes handle the rear sprocket changes pretty well.

Yac made another good point about getting home. Sometimes you pop out on the logging road, and want to beat feet. Nice to make a quick sprocket change and fly on home. All depends on how far it is back to the truck.

One trick I've used on chains lengths is to cut my chain in two places (two master links), and carry to different length sections, one for the bigger sprocket, and one for the smaller. I cut the chain such that I never have more than one master link on the drive side at a given time. I've used this concept more for racing than woods riding, but the same principle would apply.

If you don't want to do the math, the rule of thumb is dropping one tooth count in the front is close to adding 3 in the rear. However, with larger sprockets in the rear, it's closer to adding 4 in the rear to drop one in the front.

50/14 = 3.571
54/14 = 3.857
50/13 = 3.846


Best of luck

Offline russ

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Re: Gearing Changes
« Reply #3 on: May 25, 2011, 06:27:39 AM »
i ride in the moutains mostly trail tight trails and i  run a 12/50 and it gives me lots of bottom end but i also got the bike this way i have never ridden with stock gearin
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Offline 1989kawasaki

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Re: Gearing Changes
« Reply #4 on: May 25, 2011, 06:29:01 AM »
i have a 12/50 too  8-)
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Offline flyingfitz

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Re: Gearing Changes
« Reply #5 on: May 25, 2011, 08:14:25 AM »
Consider a 51 on the back and get a 14 and a 15 for the front.  14 will give you that lower gear drivability in the woods and the 15 will be very close to stock for the higher speed stuff.  I would avoid the 13 front with any size rear for possible case rub issues.

Fitz

Offline russ

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Re: Gearing Changes
« Reply #6 on: May 26, 2011, 06:06:52 AM »
my 12 in the front has caused major rubidge but i think the guy before my grinded some of the case away so it and the chain would fit on but i think i might go to a 14 not sure will i losse alot of bottom end if i change from a 12 50 to a 14 50
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Offline ewilly

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Re: Gearing Changes
« Reply #7 on: August 02, 2019, 04:05:28 PM »
12 in the front sounds like a major challenge and chain wear is a consideration