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I'm about to replace a back axle for the first time, and I'm confused about whether I need to remove the cassette to do this properly. This is relevant because I don't have the tools to remove the cassette, so I'm wondering should I hold off on the job until I have those tools.

Here's the issue. My back wheel uses a cup and cone bearing system. I understand how tightening the cone works and I have all the tools, but the problem is that when the axle is inserted the cassette side cone is concealed by the cassette, and so it can't be tightened when the axle is in.

My idea for getting around this is to fix the cassette side cone on the axle using the associated nut while the axle is out, then put the axle in the hub, and then tighten the other cone and nut to finish the install. Is this reasonable?

(Sorry if this is a stupid newbie question, but neither my Zinn book nor the online articles and videos discuss the relationship between installing the axle and the cassette.)

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    You should remove the cassette.
    – Batman
    Oct 12, 2016 at 16:50
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    With a standard axle design the problems are (at least) two-fold: 1) You may need to access the locknut on the cassette side after the new axle's installed to do fine adjustments, and 2) in some cases the cone may be larger than the hole in the cassette. There's also the point that you will not be able to clean, inspect, and relube the cup on that side. (Generally, the cassette tool and chain whip are not that expensive.)
    – Daniel R Hicks
    Oct 12, 2016 at 17:05
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    You can also quite easily make your own chain whip if you have an old length of chain lying around. Also, check to see if there is a bike co-op in your area. Many cities now have a bike co-op with tools that can be used for free or for a small fee.
    – Kibbee
    Oct 12, 2016 at 17:37
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    Personally I'd buy the tools. That way you have them for ever. If the drive-side cone will fit through the freewheel, then you might be able to do it with the freewheel in place. If you have a cassette, you'll have to get the lock ring off to access the bearings anyway.
    – Criggie ♦
    Nov 5, 2016 at 23:24
  • James - would you mind adding an answer to this question ,so that others know how you got on and what you did? Feel free to "accept" your own answer.
    – Criggie ♦
    Nov 5, 2016 at 23:24

1 Answer 1

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It is possible to do this, at least with some cassettes/freewheels, either in an emergency where you don't have the right tools with you (but see here for a small cassette tool), or where you can't easily find the right freewheel remover for an old bike.

If you are at home, it isn't urgent, and you have a modern freehub, don't bother with this, just buy the proper tools first.

Use a cone spanner and normal spanner on the non-drive side to loosen that locknut, then remove the locknut and nut. If necessary (because the drive side locknut undoes and you can't reach the cone), hold the axle with a vice, or vice-grip wrench - you will chew up the thread, but you were going to replace it anyway. (If you have to reuse the cone and locknuts, undoing them over a chewed up thread may damage their threads, so try to avoid that.)

(If the axle is broken, you don't have to undo anything, just pull half out each side.)

Withdraw the axle and drive side cone from the cassette (this is where @Daniel's "in some cases the cone may be larger than the hole in the cassette" may make it impossible).

Clean the cups - it is a bit awkward doing one inside the cassette, but not impossible.

Tighten the drive-side locknut and cone against each other, hard. Insert the axle. Do up the non-drive cone slightly tighter than you want it to end up. Do up the locknut, then tighten the cone and locknut against each other. If it ends up wrong, undo, adjust, and repeat. It is tedious to do this without being able to use a cone spanner on the drive side, but it is possible. (You can put a spanner on the drive locknut, but if it becomes unlocked, you'll have to take the axle out and start again.)

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  • It's true that in some cases this will work. But it's the exception to the norm by a pretty good margin. Most hubs encountered will have something that can't make it past the lockring, either a seal or the cone itself. I think you also need to address the fact that most people reading this looking for information are going to be oblivious to the need to very carefully ensure the bearings remain or are put back into place down there, which is fiddly at the best of times, and if the axle needs replacing then we're talking about an average case situation where the hub is in bad shape.
    – Nathan Knutson
    Nov 11, 2016 at 18:40
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    If you use bearings with a retainer cage, it's trivial. But in general, yes, that's yet another reason why I advised against it in the normal case.
    – armb
    Nov 12, 2016 at 11:42

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