Gearing change

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DonnyV
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Gearing change

Post by DonnyV »

Hey guys got a couple questions

So I've been wanting to try new gearing to see what the difference is. I've been riding stock gearing (13/47) for a year and a half but I read and from listening to friends I should change my rear sprocket to a 49. Well my chain and sprockets are new and didn't want to change them out yet so I purchased a 12 tooth front sprocket just to see how I liked it and wow what a difference way more snap off the bottom and I can ride a gear higher. So my question is is there anything negative with using the 12 tooth in the front, anything to watch out for. And when I do get new chain and sprockets and I go back to the 13 tooth front what would I get for the rear (48,49), I know I would have to get a longer chain also. Thanks for your time guys have a great day
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SS109
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Re: Gearing change

Post by SS109 »

12t sprockets wear out a lot faster than a 13t and they also wear the chain out faster as well. It all has to do with the fact you have less surface area to hold the chain and your making the chain go around a tighter turn on the c/s sprocket. Plenty of people run them that way and love it. Just keep a eye on the wear.

On changing the rear down the road, going 13/51 is the closest to a 12/47. It will be just a hair lower by .2% so even better low end snap but it will reduce top speed by the same amount. A 13/50 will reduce the low end snap )versus 12/47) by 1.8% but will increase top speed likewise. Here's an online calculator so you can see it yourself https://sprocketcalculator.com/ Pay no attention to the links part, unless you know how many links you currently have, as it doesn't affect gearing ratios.

Now, what should you go for? I personally wouldn't go lower than a 13/50 as that's already giving up a lot of top speed but that's just my opinion. That's a 6% drop from 13/47 and that's something you will definitely notice. However, only you know what you like to ride as far as terrain and speeds. Some run the 13/51 and swear by it for nasty technical riding.
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DonnyV
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Re: Gearing change

Post by DonnyV »

Thanks for the input, exactly what I was looking for. I really like the ability to have one chain and different gearing options for different rides, lately I've been doing slow technical so this was great, this forum rocks
03 220 w/fmf rev, RB head mod
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MoonStomper
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Re: Gearing change

Post by MoonStomper »

I tried the 13/49 for awhile. Then Jeff Fredette recommended the 13/46. I found the bike was smoother with better suspension action using this higher ratio for hare scrambles.
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