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Singlespeed & Fixed Gear "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!"-- Henri Desgrange (31 January 1865 - 16 August 1940)

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Old 01-24-08, 02:08 PM   #1
MrCjolsen
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Does moving your wheel change the bikes geometry?

When you have horizontal dropouts?

When I flip my rear wheel, I go from a 15t cog to a 17t cog. With the horizontal campy dropouts I have, I know it raises the rear wheel slightly.

However, is this enough to be felt and warrant an adjustment of my bars or saddle? Anyone else have experience with this?
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Old 01-24-08, 02:13 PM   #2
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No, the point where the force of your wheel is applied is where the dropouts join the rear triangle as far as I know, so changing wheel placement in the dropouts shouldnt change geometry, and evev if it does, it will be minimal. I wouldnt worry about it.
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Old 01-24-08, 02:15 PM   #3
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if you have to ask online and you can't feel it than it doesn't matter
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Old 01-24-08, 02:16 PM   #4
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No.
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This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.
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Old 01-24-08, 02:20 PM   #5
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^^^^

Yes it would change the wheelbase of the bike, due to using the same chain length, when you switch from 15 Tooth to 17 Tooth (larger diameter), all it would do is move your wheel forward by what ever fraction of an inch of the difference in the diameters of the two cogs.

Nominal differences really, you shouldn't notice a thing.
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Old 01-24-08, 02:57 PM   #6
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why does the rear wheel raise? i don't get what u mean by that, because if it's horozontal then it should be shifting laterally.
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Old 01-24-08, 02:59 PM   #7
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most horizontal drops aren't completely level, infact i've never seen them level ... track drops are usually level
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Old 01-24-08, 03:08 PM   #8
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from what i have read, the back wheel is minimal. when you start changing the front wheel is when big things happen
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Old 01-24-08, 03:22 PM   #9
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It totally matters! Even a couple miles of riding a flipped wheel without a professional resetting of your bars, seat, and a possible stem swap could lead to a critical geometry failure!








j/k yer fine.
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Old 01-24-08, 03:27 PM   #10
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^^^^

man that would suck to have happen. That frame AU ?
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Old 01-24-08, 03:32 PM   #11
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Quote:
Originally Posted by Metricoclock View Post
^^^^

man that would suck to have happen. That frame AU ?
Donno, random google image of "bike hit by car"
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Old 01-24-08, 03:35 PM   #12
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When use 15 let 15psi out front tire. when back to 17 let 15psi out back tire
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Old 01-24-08, 07:25 PM   #13
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Quote:
Originally Posted by Metricoclock View Post
^^^^

Yes it would change the wheelbase of the bike, due to using the same chain length, when you switch from 15 Tooth to 17 Tooth (larger diameter), all it would do is move your wheel forward by what ever fraction of an inch of the difference in the diameters of the two cogs.
He didn't ask about geometry, he asked whether the change would affect handlebar and saddle placement.

Quote:
Originally Posted by The other guy asked
why does the rear wheel raise? i don't get what u mean by that, because if it's horozontal then it should be shifting laterally.
The horizontal drop outs typically have a slight angular alignment such that repositioning the wheel does not affect the relationship between rim and brakes.
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This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.
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Old 01-24-08, 08:00 PM   #14
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Quote:
Originally Posted by dobber View Post
He didn't ask about geometry, he asked whether the change would affect handlebar and saddle placement.
Check the thread title again chief
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