Replacing a rear bike wheel, what do I need to know

I have a Schwinn 21 speed ‘Woodland’ bike (which is more of a city/road/gravel bike than a woods bike). I got it used and a rear spoke is broke, the wheel is a bit out of true, but not too bad considering the spoke. It does look like it has a lot of wear and I do think the spoke broke from fatigue rather than impact. I feel that it would be better to replace the wheel than just the spoke (also the bearings don’t seem smooth). And from there I pause as I’m not sure what to get.

What I do know is tire size for the rear is 26x1.50 (front is 26x1.75 which I may want for the rear). It’s a thru axle mount (not quick release), and I believe it’s a freewheel, but not sure. It has cantilever brakes.

So what type of wheel do I need? I’m not looking for expensive, but cheap and serviceable.

So where do I go from here, liking to do it myself, so I’m really looking for the challenge and learn and not looking to the bike shop option. Actually I got this bike partly to learn from.

I would not mind getting a quick release however the family has some thru axle’s as it is so carrying a wrench is needed anyway so no biggie if it stays thru axle.

Also could I get a cassette hub instead of a freewheel hub? And would I even want to do that? Again I’m not totally sure I have a freewheel but it does look that way. Would the de-railer work with either? Should I replace the gear rings, again would by old de-railer work on new gears?

Thanks

The thru axle threw me off, I am pretty sure you have a threaded axle and not a thru axle. Which means that you have a fairly inexpensive bike that probably isn’t worth sinking much money in. So I suggest that you replace the spoke, and learn how to true the wheel. It might be a bit of a pain if the broken spoke is on the drive side, you’ll have to remove the cassette or freewheel to get the spoke through the flange.

Other than that, a bike shop might be able to get a replacement wheel, or one off of an old bike. Also, check to see if your community has a bike repair resource, you may likely end up with a used wheel for this repair.

I had a spoke go out on the rear wheel of a Schwinn Voyageur, also a 21-speed. Had it trued at the bike shop and on my way back to my car in front of the shop I felt a twang and damned if another spoke hadn’t broken.

I took the wheel to another bike shop and they trued it. A few weeks later another spoke broke, then another shortly after.

They suggested a new wheel and guessed the spokes might be fatigued from a long period without adjustment. The old wheel used a freewheel cogset and these days the cassette style is more in vogue, so there was going to be an additional cost there.

When all was said and done it was actually only a bit more expensive to buy a replacement bike of similar value than it was to replace the wheel and cogset. At the time I didn’t have a garage or any space to work on the bike or I might have tried doing the work on my own.

“thru axle” threw me for a loop too.

For the uninitiated, ‘thru axle’ in cycling lingo refers to the new-fangled one-piece axles on disc brake bikes that screw directly into the frame. They actually pull completely out of the wheel when mounting-dismounting the wheel from the frame. Normally the sort of axle the OP is referring to would be called a solid axle.

Anyways, any replacement 26" wheel with 7-speed cassette should work, provided that the brand of the cassette matches the brand of the derailleur. I’m not sure it’s even possible to get a freewheel setup these days. From a functional perspective for a casual cyclist cassette vs freewheel doesn’t make a huge difference. A freewheel makes it harder to service cup & cone wheel bearings, and places higher stress on the rear axle as the drive-side bearing is further inboard, but if you’re not frequently repacking your own bearings and don’t weight 300lbs and habitually hop up and down curbs neither of those are terribly likely to be crucial differences. Except, as I say, I’m not sure you’ll find a replacement wheel that isn’t freehub w/ cassette these days. Either way, when messing with cassettes or freewheels, specialty tools are required.

All that said, if you’re wanting to learn I would try to service the wheel. While it’s true that one broken spoke might be a precursor to a lot more, it needn’t be, and the cost of a single spoke and a freewheel/cassette lockring tool (plus chain whip if it’s a cassette) should be minimal. Identifying the correct tool you need is important, as there are a lot of different ones and they are not interchangeable. They are tools you should have anyways if you intend to maintain your own bike. Re-pack the bearings while you’re in there, and you’ll be good to go. These are both fundamental bicycle maintenance tasks you should know how to do if you intend to learn how to maintain a bike.

If you need help identifying what you’ve got, you could post pictures here and I’ll try to help. Also r/bikewrench on Reddit is a forum completely devoted to people posting “how do I fix this” queries with lots of knowledgeable people answering.

Great post @Gorsnak! I agree if you want to learn go ahead and learn on the wheel you have. If the broken spoke is NOT on the drive side (with the gears), then the fix is very straightforward, once you have the correct replacement spoke and a spoke tool (together at your LBS or REI will be less than $20 - bring the wheel with you so they can get the correct length spoke). There are going to be lots of video online, but the basics are:

  • remove the wheel from the bike,
  • remove the tire and tube,
  • remove the rim tape or runner that covers the spoke nipples (yes, that’s what they are called),
  • remove the broken spoke from both the rim and the hub,
  • thread the new spoke thru the hub and aim toward the empty hole in the rim (pay attention to the way the other spokes are threaded around one another and copy),
  • insert the re-used spoke nipple and turn a few times by hand to grab the threads on the spoke,
  • then use the spoke wrench to tighten a little.

Put the wheel back on the bike and use your brakes to true the wheel, applying quarter-turns to the spoke nipple (tighten or loosen) until the wheel is straight. While you are at it, you can check for other spokes that are loose, too tight, or damaged. Replace the rim tape, tube and tire and you are on your way. If the work is on the drive side, you will have to remove the gears as mentioned, but the spoke replacement is the same process.

Just an update, yes it’s a solid axle. Thanks for the lingo and all the help here. Yes the spoke is on the drive side however…

Today a guy was selling a 26 in bike wheel on facebook marketplace for $20 he says he bought the wrong size.

So I just got a new, never used before it appears, wheel complete with tire and gears (Shamano 14-34t?) and tube, however the person put a schader valve in and it and the hole is obviously presta sized, so I will need to get that tube (do people drill out those holes to enlarge them)? It’s a solid axle. I won’t be able to try it for a few days, but excited by the find.

How on earth do you put a Shrader valve onto a rim drilled for a Presta? Or is it not assembled? I don’t see any particular reason you couldn’t drill the hole larger, though you’d want to take a lot of care filing any leftover burrs smooth. Presta vs Schrader never even occurs to me in these discussions because I always just take it as a given that all bicycle valves are Presta.

With regards to the new cassette, assuming it is 7 speed and the old drivetrain was also Shimano (I don’t think you’ve said), it is probably compatible, but there are a couple potential issues. First, depending on the model of your rear derailleur, it may or may not be compatible with a 34T largest cog on a cassette. Back in the day they could only accommodate up to 28T, for example. Second, if the largest cog on the old freewheel/cassette is smaller than 34T, then your chain won’t be long enough and if you try to shift into big ring-big cog combo you’ll tear your rear derailleur apart. Obviously if the old one is also 34T there’s no problem.

They just put the valve in the hole, only the threads were small enough to get through however. All the rest of the stem is inside the tire.

Thanks for the heads up on the chain length, I suspect that’s the case. And yes it’s a Shimano derailer however I don’t think it can accommodate that large ring, but again I can’t do anything for a couple of days with that bike.

If you can determine the specific model of derailleur we can figure out if it can handle a 34T cog.

I’d get a presta tube.

You can still get freewheels.

Also, the alignment of the rear gears with derailleur could be off since it is a different wheel. If you install it and go thru the gears if it is not shifting smoothly, you should be able micro-adjust using the derailleur tensioner.

If it’s compatible, jump on it.

I jumped all over that, it’s a beautiful wheel.

Absolutely, you can drill the hole out. Drill it to 21/64. And definitely file the new larger hole smooth.

I myself really prefer Schrader valves over those fiddly little Presta valves that break too easily.

Also, here’s the ultimate online resource for what-fits-what kind of stuff. Super-useful. kanicbird, you’ll find the answers to any question you can think of here.

https://www.sheldonbrown.com/harris/#articles

Which you said but I missed, sorry.

If you have schraeder on the front, drill the rear for it as @Saintly_Loser suggests. Switching between the two is a PITA and filling up at an air station is easier overall.
The 34 T rear shouldn’t be an issue for a MTB derailleur, even my 85 Bianchi Grizzly could handle it.

This new wheel has some aero ring that may require a longer valve stem, I will have to see if a schraeder would work at all.

Ah, that will complicate things. In that case you may want to just run long stem Presta on both. There’s nothing stopping you from running longer Presta on one and Schraeder on the other, but I like having only one type of spare tube with me in my panniers. YMMV.

Sigh.

I used to be big into cycling and wrenching on bikes, and Sheldon was a bit of a legend.

When I was on a trip to Mass., I paid a visit to meet him. He was sick. We talked for a long while. I asked what, if anything, I could do as my way of thanking him for his endless generosity to the cycling community.

Just buy a Harris Cyclery jersey, he said.

He was sui generis.

Yeah: mixing valve stem types (at least on a single bike) leads to madness. I went all Presta (across all my bikes) at some point, in no small part because of the other cyclists that predominated my area. If you got a flat, anybody could loan you their pump or a tube to get you on your way.

YMMV.

The Schrader crowd – my sense is – always seemed less likely to have spares or pumps or anything. It was usually older and/or less expensive bikes and people who were sure there was nothing they could do with tools or a spare tube (ignoring the possibility that a well-meaning cyclists c/would help them out with the stuff they might have carried).

The derailer is a Shamano 200 GS, the gear is MegaRange MF-TZ31 Superlow 14-34T

I put it on and carefully turned it (bike upside down, not riding it), it was able to climb onto that big gear (34), but looks like it’s not centering on it, riding the side of it. I also tried carefully the large front ring, it did manage to work but the chain is at it’s limit and the rear derailer is very far forward.