Singlespeed & Fixed Gear - 47/17 Gear Ratio?

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View Full Version : 47/17 Gear Ratio?


dre808
10-08-12, 01:17 AM
I just joined the forums so hopefully I put this in the right place...

But anyways, I was thinking of running a 47/17 gear ratio on my fixed gear. Right now I'm running a 48/16. I go pretty fast, it's not hard to skid but the only problems are: its hard to start pedaling, hard to climb hills, and has only 1 skid patch. I'm interested in the 47/17 because of the 17 skid patches (even though brakes are my primary way of stopping, I skid a lot just for fun), and because the gear inches is 74 which I think is a good number? I really don't know much about gear inches or gain ratios, so could someone explain that to me? Anyways, do you guys recommend this ratio? What are the pros and cons? Is there a ratio better then this? I'm looking for a ratio with a good amount of skid patches, a ratio that's easy to skid, and a ratio that allows me to go fast AND/OR climb hills easier, but looking more towards climbing hills. I live in Hawaii by the way where its mostly flat ground, but most of the time I need to go up a hill to get back home. Thank you!


IthaDan
10-08-12, 01:56 AM
Sounds like a good ratio to me. 70GI seems to be about the magic number. just do it, then double back if it's not what you were expecting.

if you can push a 48/16, why not cave your money and change just one of the two gears?

ben4345
10-08-12, 02:12 AM
No, having 47/17 will make the earth implode. DO NOT DO IT!


dre808
10-08-12, 02:18 AM
Sounds like a good ratio to me. 70GI seems to be about the magic number. just do it, then double back if it's not what you were expecting.

if you can push a 48/16, why not cave your money and change just one of the two gears?

Does GI mean gear inches? If it is, what is gear inches? Sorry I'm new to these terms.

IthaDan
10-08-12, 02:37 AM
yes. gear inches. Essentially it's an arcane metric that's been adopted to standardize gear ratios over many wheel sizes and gearings.

It's the diameter, in inches, that a directly driven wheel (like the big one on a penny farthing or a kid's tricycle) would have to be to achieve the same gear.

If you don't know what any of those terms are, use google.

dre808
10-08-12, 02:52 AM
No, having 47/17 will make the earth implode. DO NOT DO IT!

Whats wrong with this ratio?

wicked ink
10-08-12, 02:59 AM
Try 48/17 first since you already have a 48t chainring. Good all around ratio.

ddeadserious
10-08-12, 06:27 AM
Try 48/17 first since you already have a 48t chainring. Good all around ratio.

x2. I've run a handful of gear ratios and like 48/17 and 48/18 the most.

Scrodzilla
10-08-12, 06:36 AM
We should have a thread where we talk all about gear ratios. It should also be a sticky so it's always right on top of the page and easy to find.

Oh, wait... (http://www.bikeforums.net/showthread.php/716371-Uncle-Sixty-s-Gearing-Primer-for-Newbs)