In search of a 20h rear hub

[themidge]

Hello everyone, hope you're having a wheely good day .
My Mavic aksium rear hub gave up the ghost recently and while I do have wheels to ride (DA c24's no less, borrowed from a friend who doesn't use them), I'd quite like to rebuild the rear rim with a new hub and spokes. I've never built a wheel before but I'd love to try it.
However, the Mavics have just 20 spokes at the back (and the front) and I can't seem to find a 20h rear hub anywhere that isn't Chris King or something expensive like that.
It doesn't need to be light (these are aksiums after all), but it needs to be not shit, and cheap (<£100). Suggestions?

Its not the end of the world if I can't do it (is it even OK to rebuild with so few spokes?) and I can still use the front for something, but these have been good training wheels, and it'd be a shame to not be able to use them.

[jch3n]

Are you sure the rim can even take standard nipples and spokes? Mavic tends to use a lot of proprietary stuff. Honestly, I think you're better off just buying a new Aksium rear wheel, which seems to be around $130 USD. You'll probably be spending close to, or more than, that on a hub, spokes, and nipples.

[alcatraz]

Take a spoke out and measure at the head with calipers. If the spokes are bladed you also need to measue the width of the widest point to see if you need special spoke holes. Give the specs to several hub seller that specialize in different brands. Bitex/chosen/dt/novatec.

Finding a 20h hub that can take the dimension of that spoke while having the same hole pattern radius could be quite a challenge. Especially if you need special features like U-shaped spoke holes (spoke doesn't pass through but simply hooks in the U).

You might have more luck finding a failed aksium rear wheel and take it's hub. That means long term project.

/a

[Miller]

I'd echo that Mavic parts are liable to be quite proprietary. Making use of a leftover used spare part as the basis for a project can lead one down a frustrating path.

Wanting to build your own wheel is a perfectly good idea. To set you on a successful course, buy a new general purpose hub and a rim and the necessary spokes. You can enjoy the freedom of parts selection to get exactly the build you want.

[Svetty]

Agree there will be lots of Aksiums out there with worn out rims and decent hubs. If you search on ebay a used one is likely to come up at some point. Before spending any money though I'd check that you can dismantle the old wheel and that the spokes and nipples survive the process well enough to be re-used.
Otherwise just get a new wheel - assuming the front one has enough life left in it to be worth matching with a new rear.

Alternatively can you just not replace the bearings - or is it the freehub that has 'died'?

[themidge]

Cheers for the replies dudes.
Yes it is the freehub that has died The rims are pretty unworn, enough that a new rear would match the front well enough. That might be the easiest and cheapest option anyway TBH.
It's true that a lot of mavic wheels have proprietary spokes, but the aksiums are normal as far as I can tell. That's a good shout on taking a hub off another aksium, which I suppose would mean that I could reuse spokes and have spares from the donor wheel. However, this last mavic hub lasted about 4500km (somewhat rough estimate) which doesn't really fill me with confidence for another one. I honestly don't mind getting a new hub and spokes.
The fewest number of holes I can find in a hub like bitex, novetec, etc. is 24 though, so it might have to be a mavic from another wheel .

[alcatraz]

Freehubs are replaceable items. Have you localized the problem? Is it in the hub body or just the freehub?

If the freehub body is chewed up by the cassette or bearings toast or the little spring loaded teeth that make up the freewheel mechanism are damaged.... then you simply replace the freehub with a new one. The manufacturers provide freehub's as spares. They are also available in two kinds for shimano and campagnolo style cassettes.

/a

[mattr]

Agree with that ^^^^^^^
We replaced a first gen Aksium hub for about 35 quid (after a mate cross threaded, then stripped the lock ring threading).
If this is still a current model, the freehub replacement will be the cheapest (and easiest) way to do it, unless the hub bits have gone as well.

[themidge]

Ah ha! I hadn't thought of replacing the freehub, which must be what's broken as it makes a really bad squeaky noise when I pedal buy not when freewheeling (regreasing it didn't last 5 minutes until it started again. I'll go into my LBS and ask about a replacement one. I think they do mavic, or at least have experience with them, when I went in at first with the problem they said that eventually mavic freehubs sort of lose the will to live .

[MayhemSWE]

When in need of service Mavic freehubs normally start making noise when freewheeling rather than pedaling. If the Aksium hub has the same weird bushing as other Mavic freehubs the internals should not be greased but lubricated with mineral oil.

[mattr]

Yup, oil. Not grease. Grease gets pushed out of the way. Oil tends not to.

Did you actually open it all up and clean it properly? Mavic hubs tend to need a bit of looking after if you use them in all weathers.

[themidge]

This freehub has certainly been a bit of a handful:
- made a horrible grinding noise when freewheeling, guy at shop took it into the back and it came back pretty quiet, I think he put some light grease in it, maybe, I dunno.
-then it started squeaking when pedalling (fine when freewheeling) so I went in again and they did something to it, but after only a week and a bit it started again and they said its probably dead. Maybe they used grease instead of oil?
- I borrowed some dura ace wheels from a friend for the mean time
If I can, I'll try to take apart and inspect the freehub to see if anything looks broken or knackered and report back.

[MayhemSWE]

There is an article on Slowtwitch about servicing Mavic hubs which I'd suggest you have a look at:

https://www.slowtwitch.com/Tech/Mavic_h ... _4006.html

[themidge]

Thanks, that looks good. I'll see what I can do when I have time (no rush on this ).

[ergott]

I have a Reynolds 20 that I removed to rebuild with a Powertap. It's yours for whatever shipping plus $15 cost. Decent hub.