Replacing Parts

Hey all, it looks like my right crank came loose and the LBS had to do some repair work… I’ve got the Nimbus 24" Muni, and have been riding it pretty hard, and I’m wondering about replacing the hub. Can I get any replacement hub that matches the spoke count, and get the LBS to replace it (and install new cranks to go with it of course.)? Am I limited to certain hubs that will fit in the frame? Last time something like this happened I replaced the entire uni (it was a cheap learner anyways ;)) and I’d rather not do that again :wink: Would it be cheaper to just get a new KH wheelset then get the LBS to do the hub work (assuming the KH wheelset fits in the frame…) I can ride the thing, but am a bit clueless on parts :wink:

You could just buy a KH hub and have your LBS rebuild the wheel. Mine have built several wheels for me. If your rim is ok, then don’t bother with the entire wheel set, unless you don’t want to mess around with having the wheel rebuilt.

As for frame width, unicycle hubs should all fit with only a little bit of persuasion. Unless you have a carbon fibre or aluminium frame, then I don’t think you are supposed to bend them.

Oh the KH wheelset will fit the Nimbus II 24" frame.

If the flanges are a different size then you might need new spokes, too. Most unicycle hubs are pretty similar so you’ll probably get away with it.

If you are riding hard and likely to trash the hub again then it is probably time for a splined hub.

Cost wise it depends on your bike shop. Building a unicycle wheel will be a bit trickier as it doesn’t fit in a normal wheel building jig so they might charge you a bit extra. If that is the case then it’ll probably be the same price as a new wheel.

Finally, wheel building isn’t difficult so you could tackle it yourself.

ATB
Nick

Re: Replacing Parts

“one wheeled stallion” <one.wheeled.stallion@NoEmail.Message.Poster.at.Unicyclist.com> writes:

> As for frame width, unicycle hubs should all fit with only a little bit
> of persuasion. Unless you have a carbon fibre or aluminium frame, then I
> don’t think you are supposed to bend them.

Right. Except I found your wordinbg a little confusing. To clarify,
it’s generally OK to bend steel frames to fit a new hub, but best not
to try that with aluminum (and especially not carbon fiber).

Ken

If you get your LBS to rebuild the wheel, it is very likely they will replace the spokes. Even if they are the same length with the new hub (whatever it might be) most wheel builders I’ve met insist on using new spokes. This will add to the cost of the rebuild.

+o}{y

I think the reason most Wheel builders insist on new Spokes are that it is much faster to cut out all the old spokes. If you’re paying your bike mechanic by the hour, imagine how long it takes for them to unscrew each spoke.

I suggest if you’re desperate about saving money to ask if they will rebuild the wheel if you unscrewed the spokes yourself. But if you’ve been rough on the wheel the spokes might not be that flash.

Yes, exactly. It’s cheaper to use new spokes. Cutting out the old spokes takes a few seconds, but unscrewing them takes five to ten minutes. And then re-using them to build a wheel takes a little longer because the threads tend to be a little corroded so the truing and tensioning takes longer.

If you are going to re-use spokes to save money then do most of the work yourself. Get a hub that uses spokes of the same length. In practice, that generally means having the same flange spacing and radius. Carefully de-tension the wheel so that you don’t prang the rim. (Unscrew all the spokes 1/4 turn, then repeat until they are slack. Once the hard tension is off you can start going with 1/2 turns.) Lace up the new hub and get it roughly true with low tension. THEN take it to the LBS for the final true and tension.

Tell them what you intend to do up front and they’ll help you a bit. It saves them work later to have you use a proper spoke lube, etc.

If it were me I’d buy a whole new wheel set and keep the old one in reserve as a spare.

There is a spoke length calculator on the unicycle.com UK site where you enter the hub and rim and number of spoke crosses and it gives you the spoke length you need. I switched out my suzue hub with a profile and the same spokes were close enough to reuse. The suzue is narrow with large flanges and the profile is wider with small flanges so the spoke length was only a couple of millimeters diferent. I think that reusing spokes is fine, bike shops like to allways use new spokes because as mentioned before its easier to cut them out than unscrew the nipples, and then they get to sell you new spokes. With stainless steel spokes and brass nipples corosion is not a problem, and neither is reusing spokes if anything used spokes are tested and any stretching they may do has allready happened.

Costs

So how much has it actually cost people to rebuild their wheels? As a baseline for me to work with… I went less than a mile today and that dang right crank went loose again… walked home :’( I’m thinking of getting the KH hub, which will mean new cranks as well… so maybe it will end up being cheaper to just buy the whole wheelset…

Re: Replacing Parts

Rebuilding your wheel can cost nothing if you borrrow a spoke wrench
and do it yourself. Otherwise, I can tell you that Kovachi Wheels who
build wheels for unicycle.com advertise $30 for a wheelbuild. You may
need new spokes when you change hub and/or rim, and that’ll set you
back an additional $15, or so.

The bearings that come with the splined KH hub are 42mm (outside
diameter), while I think most unicycles use 40mm. Unless your frame
accomodates the larger size (e.g. currently uses shims to fit the
bearings) you can’t use the splined KH hub. You can go Profile for
about $110 more.

As for price, by the time you’re done with hub, cranks, spokes,
bearings, and wheelbuilding cost, you’ll probably save a few dollars
and end up with a better built wheel compared to the KH wheelset on
unicycle.com. The advantage of the wheelset is it comes with a great
rim plus tire, tube, etc. If you go Profile, you’ll definitely save
money buying the hub a la carte.

Ken