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[Closed] Single speed Gear ratios: 32:18 to 33:20?

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[#5926677]

What's the effect please? And with the 33 up front, what do I need on the back to simulate 32:16?


 
Posted : 06/02/2014 8:54 pm
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17??

I ride 34:21 in the hills and 34:19, prolly doesn't help you but hey, when have I ever been helpfull eh? ๐Ÿ˜†

Edit, what are you trying to achieve ? That 33:20 gives 1.71 thereabouts and my examples about give similar except my 34:21 is lighter for the hills..

Are you rattling the flat cos that 33:20 is something like 1.65 which will be hard going uphill, but hey take all that with a pinch of salt cos I've had 2 G&Ts

Xx


 
Posted : 06/02/2014 9:12 pm
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google gear calculator, put your sizes in and see how they match up.


 
Posted : 06/02/2014 9:29 pm
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Well Sheldon brown gives me 3.4. Means nothing to me, I might need some kind of explanation for simple people.


 
Posted : 06/02/2014 9:36 pm
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Go on the Sheldon Brown gear calculator and get it to work it out in gear inches rather than ratio.
Gear inch is the number of inches you'll move for one revolution of the pedals.

Basically you want the number for the two gears to be as close as possible to get the same effect.


 
Posted : 06/02/2014 9:38 pm
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Gear inch is the number of inches you'll move for one revolution of the pedals.
Not quite, it's the equivalent diameter of a penny farthing front wheel. To determine how far you will travel for one pedal rev. you need to multiply by pi.


 
Posted : 06/02/2014 9:53 pm
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I've also messed this up by not telling all. Let's start again.

I'm moving from 26" with 32:18, which I would have changed to 17, to a 29er with 33:20.

I'm wondering if I need to by a smaller cog for the 29er to replicate the 26er at 32:17.


 
Posted : 06/02/2014 9:58 pm
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46 inch on 32x18 26er
48 inch on 33x20 29er


 
Posted : 06/02/2014 10:13 pm
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I just read an article about Gain. So as Edrics pointed out, I'd go 2 inches further on one pedal rev, but actually it's nearly the same as the 26er. Going to 18 would be 53 on the 29er so harder up hills faster on the flat.

Got it, thanks.

Oh and @ bike buoy - good luck with the hangover in the morning..,,


 
Posted : 06/02/2014 10:33 pm
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Yes

Definitely do that.


 
Posted : 06/02/2014 10:34 pm
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26er on 2.3" tyres, 32:17 = 50 gear inches
29er on 2.3" tyres, 33:20 = 48 gear inches
29er on 2.3" tyres, 33:19 = 50.6 gear inches

Edit: 29er on 2.3" tyres, 31:18 = 50 gear inches

Think of gear inches as the smaller the inches the more granny it will feel, the bigger the inches the more manly!


 
Posted : 06/02/2014 10:34 pm