Changing hub axle diameter
07-05-13 | 06:33 PM
#1
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Bikes: 2010 Masi Gran Criterium, Motobecane ca. 1980 Grand Jubilee, 1984 Trek 500, Specialized Camber Comp 2014
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?
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?
07-05-13 | 06:53 PM
#2
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Bikes: 2008 Novara Randonee - love it. Previous bikes:Motobecane Mirage, 1972 Moto Grand Jubilee (my fave), Jackson Rake 16, 1983 C'dale ST500.
Well, the main problem is getting a dustcap and cone that are compatible with each other, the cup and the fork spacing.
Last edited by cny-bikeman; 07-05-13 at 06:59 PM.
07-05-13 | 08:47 PM
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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?
07-05-13 | 08:53 PM
#5
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Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
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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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
07-05-13 | 09:31 PM
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Bikes: Current 79 Nishiki Custum Sport, Jeunet 620, notable previous bikes P.K. Ripper loop tail, Kawahara Laser Lite, Paramount Track full chrome, Raliegh Internatioanl, Motobecan Super Mirage. 59 Crown royak 3 speed
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.
