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I just bought new wheels for an older Schwinn frame. I don't know the date it was made, but it's a steel frame and as built it had stem shifters and a cup-and-cone bottom bracket, etc. Probably from some time in the 80s, I estimate.

The spacing between the rear dropouts on the frame itself is 130mm; the new rear wheel and hub arrived spaced to 120mm. It's a flip flop hub with a solid axle (no quick release). I am able to get the hub to fit snugly between the dropouts just by tightening the axle nuts, since the steel frame will bend to make up that 5mm on each side pretty easily.

Is this a safe setup? Or do I need to add spacers to the hub to fit the 130mm frame without any bending?

  • Send me a picture of the your bicycle and I want look it properly before taking any decisions and then I give you any advice – Rajender singh Jun 14 at 1:25
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    120mm is quite small - is it a track frame? 126mm was one common size for the OLD measurement. – Criggie Jun 14 at 7:16
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    @Criggie the frame is 130mm - it's the hub/wheel that's currently spaced to 120mm out of the box – hairboat Jun 14 at 17:34
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No, that much of a spacing difference is generally a bad idea even with steel because of the increased stress it causes in the dropout area, which may cause or contribute to failure of the frame in the dropout area over time.

How bad it is exactly on a given frame is difficult to pin down. But it's observably true that the right rear dropout is a common failure point from fatigue on heavily ridden bikes where everything else is holding up well. The static stress that gets created from having the frame squeezed down can only add to that.

Presuming it's steel, just respace it to 120, and then re-align the dropouts afterward. A side benefit is that you get to align the rear end at the same time you respace it, so it can be perfect on both fronts.

Having the spacing and dropout alignment be right will also make tensioning the chain during wheel re-installation be a much smoother process.

  • Sorry, when you recommend respacing, you mean respacing the hub to 130, right? – hairboat Jun 14 at 17:34
  • @hairboat No, the frame. Respacing the hub may be a good choice if it's possible, i.e. if it's a standard axle hub or a nonstandard axle one that can take spacers and also has the length to give, but that excludes a lot of track hubs and you don't say what you have. – Nathan Knutson Jun 15 at 5:39
  • Got it. How do you respace the frame itself? I've never heard of doing that. This is the wheel, btw. A bit generic so no useful details on the hub, but IIRC (I am out of town right now) there is room on the axle for spacers. I also have access to a shop where I could swap out the axle for a longer one if needed. – hairboat Jun 17 at 13:40
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    That hub does use a proprietary shouldered axle. If it's got room for spacers without running out of axle, then that's certainly the easier way to go. Respacing the frame is a question all its own. There are questions on here about it, and sheldonbrown.com has a good tool-minimal procedure for how to do it. – Nathan Knutson Jun 18 at 6:49
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You don't have to add spacers to be safe. With 5mm play per side it's more of a squeeze than a bend. On a steel frame you'll be fine.

It is handy to have a wheel that actually fits. It's nice to be able to spin the nut down and tighten it up with a few turns of the wrench rather than wrenching the frame down to fit the hub spacing. You might be able to get away with adding a washer on each side between the hub and the frame to take up the space.

Another thought, if you space the hub so that all of the extra 10mm is on the non-drive side then you could re-dish your wheel so that it's more in the center of your hub. This would make the spoke tension on both sides of the wheel more even. It's kind of a bike geek thing to worry about that has no impact on most people's riding.

Wheel Dish

When rear wheels are built properly, the spokes on the right side are made tighter than those on the left side, pulling the rim to the right, so that it is centered with respect to the axle (and to the frame.) Viewed edgewise, a rear wheel built this way resembles a dish, or bowl, since the left spokes form a broad cone, while the right spokes are more nearly flat. Sheldon Brown

  • Good note on the re-dishing thing. For this bike I probably won’t since I plan to swap it back and forth (fixed gear side vs freewheel side), but useful to know for future projects/others’ benefit! – hairboat Jun 13 at 19:30
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    Since it's a fixed/free hub, it most likely is equal regarding flange spacing. Ergo, re-dishing would just mess things up. – Walto Salonen Jun 13 at 19:39
  • @WaltoSalonen good point, I forgot that hairboat said it was a flip hub. – David D Jun 13 at 19:52

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