Forum: bicycles.stackexchange.com
Tags: <mountain-bike><wheels><freewheel><axle><freehub>
Title: Could I replace a hub on a wheel?
Question: I have a freewheel and I keep bending the axle, however the rim, spokes and tire are all fine, does anyone think it would be possible to unscrew the spokes, buy a new hub that has a freehub, install that with maybe new spokes and my previous rim? (And also buy a cassette) because I don't see the point in buying a whole new wheel just for the hub.

Answers:
sents: text: Simple answer:
text: yes, but it’s not worth doing.
text: Cost of hub, spokes, nipples and having wheel rebuilt will exceed the cost of a new wheel.
text: Even if you re-use the spokes a new wheel will still be cheaper.
text: Wheel building requires special equipment, expertise and time to do correctly.
answer_details: author: bicycles.stackexchange.com/users/24228/Argenti Apparatus
score: 7
sents: text: Yes - I have personally done this, by installing an 8 speed cassette freehub into a wheel that had a 6 speed freewheel.
text: The donor was a 26" MTB wheel, and the recipient was a 20" wheel for my folding bike
text: It was only worth doing because I had a donor wheel
text: and I was able to reuse the 20" spokes well enough.
text: I even reused the 8 speed cassette and chain.
text: My purpose was to get access to smaller and larger gears, because the freewheel was a 14-28
text: and I now have an 11-32.
text: The downsides were Assembling used parts can be a bit fiddly, might need some finangling to get things lined up.
text: Used parts are dirty and less fun to assemble Used parts will be worn and slightly closer to breakage than new parts.
text: It took several hours to assemble, and I messed up the location of the valve hole.
text: Upside, I have a perfectly working, true, QR-based, 8 speed 20" rear wheel and that bike has 2000 km on it now.
text: You'll need parts and some normal bike repair tools: Spoke nipple tool and probably some spare nipples Cassette removal tools - chain whip and lockring tool Freewheel removal tools - a bench vise and a freewheel tool, OR a grinder with a cutting wheel
text: (mine was a non-removable chinese thing hence power tools) Chain tool Lubes
text: Either a truing stand, or some way to use your bike frame/fork to true the wheel.
text: Feel free to ask further clarification questions.
answer_details: author: bicycles.stackexchange.com/users/19705/Criggie
score: 7
sents: text: As the others have already stated: Yes, it is possible, but ...
text: However, I feel that the really important message has not been transported yet: Building a wheel is not easy for the uninitiated.
text: Yes, it can be done.
text: Yes, you will likely get something that looks like a true wheel.
text: But you may easily end up with many broken spokes the weeks after.
text: The critical part about building a wheel is, that you need to apply even tension to the spokes.
text: Fail to do so, and they may break very quickly.
text: And with even tension, I really mean very even.
text: It won't suffice that they feel evenly tensioned to the touch, the tolerances are surprisingly small.
text: If you have a musical ear, that helps a lot, as you can just tune your spokes (that's what I do, at least).
text: However, doing so takes time.
text: Time that may be better spent on other pursuits.
text: After all, when you adjust the tension of one spoke, 35 other spokes have their tensions changed slightly as well...
text: That said, building a rear-wheel with a cassette is an additional challenge, as you need to build it asymmetrically.
text: Consequently, the spokes on one side need a much higher tension than on the other side.
text: With the tuning approach, that's two different tones, the exact pitch of which depends on the geometry that you aim for.
text: So, if your goal is to get to know how your bike is built, go for it .
text: You can learn it.
text: But expect to pay for these skills with a significant amount of time, and likely broken spokes.
text: If your goal is just to save a penny, think twice : buying a new wheel may save more in terms of time than you can save in money by building yourself, and the bought wheel has less risk of failing quickly.
text: Of course, this economic consideration heavily depends on the price tags of the parts that you are trying to save.
text: If your rim costs 500$, you better keep it, no matter how much time you need to invest into building the wheel.
text: However, for a standard, off-the-shelf 20$ rim, buying a whole wheel is very likely the more economic option.
answer_details: author: bicycles.stackexchange.com/users/36555/cmaster - reinstate monica
score: 6
sents: text: Of course it is possible, you're simply building a new wheel with some used and some new parts.
text: Unless we are talking about carbon rims where the spokes are glued and the wheel is trued in the factory already.
text: When doing that take the following into consideration: is the new hub as high as the old one (you have high flange hubs) - if not, new spokes will be needed new hub (the one accepting a cassette) will be asymmetrical - spokes on the non-drive side will reach to the very outside of the whole assembly while the spokes on the drive side will reach to like 2/3 of the complete assembly width as there needs to be some room for the cassette.
text: Most likely the spokes you have will be too long and will protrude through the nipples.
text: Either you need to buy a new set of spokes or trim the existing ones is your rim in good condition - when using rim brakes the rim should be replaced once it is worn out if all the spokes and nipples can be reused
text: - I hope you won't break any of those while disassembling if you are using the nipple washers, you most likely need a new set once the wheel is laced, it needs to be trued and dished - either you outsource it to someone with proper tools and expertise or you do it yourself
text: (a truing stand is almost a must) Good luck!
answer_details: author: bicycles.stackexchange.com/users/34697/Mike
score: 4
sents: text: Yes, one can do this.
text: But you ask "Can I ...?"
text: (my emphasis) and the answer is "probably not, at least not right now.
text: " Please don't take this the wrong way, but building a wheel requires a lot of skill and equipment and the fact that you're asking the question suggests that you don't have those.
text: Unless you're dealing with a particularly high-end wheel, rebuilding it will be more expensive than just buying a complete wheel, especially once you factor in the value of your time.
text: However, if you want to learn how to build wheels as a hobby project, then go for it.
answer_details: author: bicycles.stackexchange.com/users/13174/David Richerby
score: 3

Summary of the answers:
It is cheaper to buy a new wheel than build one from parts. Building a wheel also requires a great deal of skill. It is worth doing if you want to learn the skills but not worth it if you are thinking of saving money.
It is possible, but usually too expensive or time consuming compared with replacing the whole wheel. It is possible to do it yourself, and can teach you about the bike, but it is a skilled job and increases the risk of wheel failure. Correct tension and alignment are important, so the right tools and a truing stand are necessary. Some of the spokes and nipple washers may break and need to be replaced.