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what if? two different crank arm lengths...

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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)

what if? two different crank arm lengths...

Old 09-25-09, 12:05 AM
  #1  
505oh505
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what if? two different crank arm lengths...

I just bought a campy super record pista crankset (nos and dirty cheap)... well, half of it, the drive side. the only problem is that the length is 177.5 (??). so I've been looking for a crank arm but can only find a 175 or a 180. if I used the 175 would my leg fall off or something? would I drift to the left when I pedal?

has anyone tried this? how did it work out?
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Old 09-25-09, 12:10 AM
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why would you want something longer than 175?
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Old 09-25-09, 12:14 AM
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cause it's campy s/r pista fool. also, I have this bike that was built for crit racing with a highass bottom bracket. I used 170's on my old ride with no death and that bb is an inch lower. the 177.5's are only a half inch longer.
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Old 09-25-09, 01:48 AM
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Originally Posted by 505oh505 View Post
cause it's campy s/r pista fool. also, I have this bike that was built for crit racing with a highass bottom bracket. I used 170's on my old ride with no death and that bb is an inch lower. the 177.5's are only a half inch longer.
half inch means a lot when you're takin' real tight corners when ridin' fixed.
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Old 09-25-09, 02:01 AM
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This is a terrible idea.
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Old 09-25-09, 04:24 AM
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Who buys half a crankset without knowing where the other half is coming from?

Someone who plans poorly-
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Old 09-25-09, 04:46 AM
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I seem to remember Sheldon strongly advising against this.
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Old 09-25-09, 05:34 AM
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Sounds dumb.
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Old 09-25-09, 06:13 AM
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2 1/2 mm isn't very much. You wouldn't think it'd make much difference but my bet is it will feel wierd.
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Old 09-25-09, 06:58 AM
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As awesome as the one Super Record crank probably is, I'm pretty positive that two cranks that actually match is going to feel a lot better, even if they're cheap cranks as your saddle height is always going to be wrong for one of your legs with this setup.

Also, 177.5 is a stupid length unless you have really long legs or have a compelling reason to be using them. On the upstroke you're going to be raising your leg 15mm higher than you would with 170s and that personally sounds like a good way to get knee pains.
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Old 09-25-09, 07:57 AM
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I'm sure your leg wont fall off, but any classiness you gained with the S/R crank, you lose because you have two different length cranks.
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Old 09-25-09, 08:06 AM
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Cause and effect:

instant jackass
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Old 09-25-09, 08:07 AM
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Throw that on ebay and buy a matched pair.
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Old 09-25-09, 08:18 AM
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you're going to **** up your body real bad. my cleat is out by like 5mm and I have to fix it cause it's ****ing me up
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Old 09-25-09, 08:52 AM
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I know someone who had a 170 and 172.5 set up. It ****ed up his leg on the longer crank because it caused him to rock side to side slightly. He would also over extend that leg at the bottom of the stroke because his saddle was set with the 170.


p.s. he didn't do it on purpose. A stupid mechanic replaced his damaged crank with the 172.5 thinking it was the same length as the other crank.
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Old 09-25-09, 08:54 AM
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Are your legs exactly the same length? Have you actually measured?
Buy your cranks accordingly.
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Old 09-25-09, 08:59 AM
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You should bend one of your saddle rails a little to lower or raise that half of your body a bit to compensate.
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Old 09-25-09, 09:08 AM
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Originally Posted by lz4005 View Post
Are your legs exactly the same length? Have you actually measured?
Buy your cranks accordingly.
I don't what what you should do if you ride with your street shoes but with clipless shoes you stack the cleat to compensate for a shorter leg.
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Old 09-25-09, 09:52 AM
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Originally Posted by 505oh505 View Post
cause it's campy s/r pista fool.
I lol'ed.
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Old 09-25-09, 09:53 AM
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People change crank lengths by as little as 2.5mm because it can feel like a very big difference. I've ridden 165, 167.5, 170, and 172.5, and my body reacts to each differently. Jumping from 170s to 177.5, first of all, sounds like an uncomfortable change to make. And secondly, I really think that riding two cranks of different lengths at the same time would be very, very uncomfortable.
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Old 09-25-09, 10:26 AM
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And just plain dumb.
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Old 09-25-09, 10:36 AM
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Old 09-25-09, 10:51 AM
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Originally Posted by Yo! View Post
that's a whole lot of woman! Iggy don't stand a chance
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Old 09-25-09, 11:07 AM
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I think this is the first time I've ever seen Iggy wearing a shirt.
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Old 09-25-09, 11:09 AM
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She's got some broad shoulders. Sure she's not a man?
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