Singlespeed & Fixed Gear - 126mm hub in 120mm track ends

I was having a rough time finding appropriate search terms to see if I could find a thread on this. Usually I just spy on other threads to find my info, as you might tell by the minuscule post count. But, onto the goods:


Would it be feasible to run a 126mm hub on a steel track frame with 120mm track-ends? I plan on getting an IRO Mark V frame but I have a 126mm fixed hub/wheel and I'd sooner not have to buy another wheel and/or hub.

Oh, and I haven't actually seen the wheel yet. I was going to do a conversion, but over the weekend I decided I'd just as soon get a more fixed specific frame as well; finicky aren't I? I'm probably going to end up sending the wheel back (assuming they'll let me) for 120mm version, but just in case, and for the sake of curiosity, the question stands. Any experiences with the Mark V wouldn't be ignored as well, though I can search for that easily enough. Thanks

Chances are that the hub is spaced to 126 with removable spacers. Just take those off (or have your LBS do it).

If not, Yeah, cram it in there. Steel is a resilient metal, it'll be fine.

howbout a 120mm track hub to go into a 126mm steel road frame?

Same thing. In either case you're relying on the elasticity of the steel chainstays and seat stays---the dropouts have not much to do with it.

For some time I had a 120 mm hub in a conversion with (most likely, never measured) 130mm stays. The only problem I had was adjusting chain tension. Cold setting would have solved this annoyance, but I ended up buying a new frame.

OP. If you take out spacers you may have to 1) shorten the axle if you dropouts are on the thinner side 2) re-center your hub/wheel with new (thinner) spacers to match the new dropouts.

Spacers are cheap. I would not cold set your rear triangle for $3 worth of spacers.

For going the opposite (120 hub to 126 rear stays), you will need a new axle ($8) and some extra spacers($3-5). Again, if it were my bike, I would not try to cold set the stays to fit my hub.

The only time cold setting makes sense is when you have a cassette road hub that needs to maintain dish and proper spacing on the drive side to accomidate the chain (so it does not rub). Or two, when you have hubs like Pauls where you don't have a way respace the hub other than to buy the correct sized hub.

when I respaced my hub (formula) I didn't need a new axle, just 10 cents worth of spacers.

I haven't seen the wheel yet. It had crossed my mind that it might be a spaced out 120mm (though, I've never actually dealt with that, I just remember reading some snippet somewhere.) If that's the case I'll certainly just take the spacers out and go from there. I'd sooner not send the wheel back (I'm impatient). Else I'll just stick it in there. I suppose 3mm of flex either side isn't really all that bad?

Another plus would be that I might just end up fixing the road-bike until I get the track frame, avoiding an entirely new layer of impatience, heh.

Any other ideas/input are welcome. Thanks for the input.

OP. If you take out spacers you may have to 1) shorten the axle if you dropouts are on the thinner side 2) re-center your hub/wheel with new (thinner) spacers to match the new dropouts.This is only true of a quick-release hub (it took me a bit to figure out what you were talking about). If it's a bolt-on, as any true fixed/SS hub should be, you can just take out the spacers and have a little more axle sticking out past the track nuts.
For going the opposite (120 hub to 126 rear stays), you will need a new axle ($8) and some extra spacers($3-5). Again, if it were my bike, I would not try to cold set the stays to fit my hub.Sometimes the axle is long enough, as it is with a lot of Formula and rebranded hubs.
The only time cold setting makes sense is when you have a cassette road hub that needs to maintain dish and proper spacing on the drive side to accomidate the chain (so it does not rub). ...I'm going to disagree with you there. Cold-setting makes a lot of sense if you bike is a conversion (read, 126 or 130mm spacing), steel, and otherwise the replacing the axle would be necessary.

...Or two, when you have hubs like Pauls where you don't have a way respace the hub other than to buy the correct sized hub.If you've got Pauls, you can afford to get a frame with the proper spacing. ;)

This is only true of a quick-release hub (it took me a bit to figure out what you were talking about). If it's a bolt-on, as any true fixed/SS hub should be, you can just take out the spacers and have a little more axle sticking out past the track nuts.
Ah. Good Point. Not sure I agree 100% on needing a bolt on axle on a SS, but understand what you are talking about on just having some more axle taken out when you have a bolt on axle.



I'm going to disagree with you there. Cold-setting makes a lot of sense if you bike is a conversion (read, 126 or 130mm spacing), steel, and otherwise the replacing the axle would be necessary.

We can agree to disagree.... but bending your rear triangle so that you don't have to spend $15 for a new axle and spacers seems like a really silly way of *NOT* spending money.

Thanks for the info; tony e-mailed me back and as was suggested, the wheel is just a 120mm hub with spacers on it, so I ordered my frame and I'm going to go ahead and put the wheels on the bike I was going to convert and ride it fixed until I get my frame and such.