Dull gearing questi...
 

[Closed] Dull gearing question because i am really not that smart.

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After shouting from the rooftops how much i love 26" wheels and will never be forced to ride 650b i have promptly ordered a new frame that comes in exactly that flavour. I still dismounted my high horse with dignity ๐Ÿ™‚

Been running 1 x 11 for about 18 months or so, 30T in the Alpine environment. 32T in the Scottish one.

So, as i have tiny bit bigger wheels coming does my gearing change in any way?


 
Posted : 20/10/2015 6:33 pm
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Bigger wheels = harder gears

you can check numbers at http://www.sheldonbrown.com/gears/

I can tell the difference between 26 and 29 but never ridden an inbetweener. It may not be that significant...


 
Posted : 20/10/2015 6:42 pm
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Seeing as 650b is only a tenny weeny bit bigger than 26", i reckon a 29.5 tooth for alpine duties and a 31.6 for scotland should see you right.

(Stick with what you have, unless you already struggle. Then take the opportunity to go down 1 tooth, unless you use N/W)


 
Posted : 20/10/2015 6:42 pm
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D'ya know? That's actually a really good question.

Before there were chains and sprockets to gear the cranks up, the ratio of crank speed to forward motion was controlled by the size of the wheel, hence the shape of the Ordinary Bicycle (nicknamed the Penny Farthing).

Therefore, my unscientific assumption is that bigger wheels = greater distance covered per turn of the crank, although in the real world the difference will be too small to notice.


 
Posted : 20/10/2015 6:47 pm
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hebdencyclist, you are now top of my favourites on here ๐Ÿ™‚

Yea i didn't think it would make much of a difference but i'm a bit geeky in that i like numbers and graphs and stuff ๐Ÿ™‚


 
Posted : 20/10/2015 6:48 pm
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gearing changes by slightly more than 5% between the two sizes

Here's a graph with numbers for you:

[img] [/img]

No. not a relevant one. sorry.


 
Posted : 20/10/2015 7:00 pm
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It's a slight difference, noticeable on a constant gradient. Best thing to do is get used to it and become stronger as a result.


 
Posted : 20/10/2015 7:04 pm
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http://www.gear-calculator.com/#

plug some numbers into that to compare.

its got 650b in it, sheldon doesn't seem to.


 
Posted : 20/10/2015 7:06 pm
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Cheers all. notsohelpful1 thanks for the graph. ๐Ÿ™‚


 
Posted : 20/10/2015 7:16 pm
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the 5% bit was the truly helpful part.

Science.


 
Posted : 20/10/2015 7:31 pm
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๐Ÿ˜› Cheers


 
Posted : 20/10/2015 7:36 pm
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It's the difference between a 26t and 27t chainring so not much more with a 30t.
I run a 26" wheel on the rear of my Liteville (650 front)for several reasons including the fact I can run a standard 11-36 cassette + 30t chainring and have as low a gear as I need for pretty big days in the hills.


 
Posted : 20/10/2015 7:45 pm