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Changing hub axle diameter

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Changing hub axle diameter

Old 07-05-13, 06:33 PM
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Roadie607
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Changing hub axle diameter

Howdy, I'm thinking about replacing the front bolt-on axle of my 29er wheelset with a QR axle. I measured the current solid axle with a pair of calipers and found the axle diameter to be 9.5mm or 3/8". Bearings are 1/4", despite being a front hub (Is this normal with mountain hubs? I know the common size for for ROAD hubs is 3/16"). I guess it goes without saying the hub is a cup and cone style.

Ideally, I would like to be able to convert the solid axle to a 9mm QR as it would allow the wheel to be used with most modern sus forks. My question is if it is possible to convert the axle diameter from to 9.5mm to 9mm for a hub that takes 1/4" balls?
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Old 07-05-13, 06:53 PM
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Well, the main problem is getting a dustcap and cone that are compatible with each other, the cup and the fork spacing.
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Old 07-05-13, 06:58 PM
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I've seen Huffy's w/ 1/4" balls in the front hub.
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Old 07-05-13, 08:47 PM
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Originally Posted by cny-bikeman View Post
Well, the main problem is getting a dustcap and cone that are compatible with each other, the cup and the fork spacing.
So I'm assuming a cone that works for a 9mm axle would be slightly smaller than one that work with a 9.5mm axle, and therefore be incompatible with the cups. Also, the dust caps would be a slightly smaller diameter and not form an adequate seal, right? How would axle diameter affect fork spacing?
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Old 07-05-13, 08:53 PM
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9.5mm QR axles exist, so your easiest option is to go that route using the existing hardware. If necessary you can turn down the outer 5.5mm of the axle by 0.5mm diameter to 9mm with a file. It'll go really fast since you're filing mainly the crests of the threads.
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Old 07-05-13, 09:31 PM
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Basically changing axel sizes is not a realistic option every part of the hub and the fork are made for the current axel. Your option if your dead set on having a quick release is to buy a axel and GR in the 9.5 size that will work there are several on the market.
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