Classic & Vintage - NR/SR Hub 126mm to 130mm Questions

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Soylent
06-01-09, 09:30 PM
My first question here so sorry if this has been beaten to death. I have read the few threads here on this topic. I have a new Cinelli Super Corsa with 130mm spacing and want to build with vintage mid 1980's SR components. I purchsed a vintage set of NR/SR hubs that were advertized as 125mm spacing, 32 hole, 35x24F. I was planning to add 4 mm of spacer on the left side, recenter everything, and then see if enough threads make it into the dropouts. If not I would buy a 10x141mm axle and build that up.

Ok. I took the rear hub apart to clean it and found that the axle was 134mm. Shouldn't a QR axle for 126mm spacing be 137mm? Is this the wrong size axle for this hub? Or did Campagnolo make NR/SR hub that was thinner (hub measurement without the axle) for a smaller spacing of 123mm?


Charles Wahl
06-01-09, 10:52 PM
http://www.sheldonbrown.com/frame-spacing.html
see info below the table.

robatsu
06-01-09, 11:05 PM
You can do it, but you may find that your dropout adjusters are fritzy - on one side they may contact the axle, the other side the qr skewer, and this may even change as you tighten down.

Beyond this and independent of axle length, the bicycle industry found that 126mm rear spacing was about the max for generally reliable freewheel applications, at 130mm bent axles started becoming far too common. This may not be relevant to you depending upon your specific weight/usage. For my purposes, I will only go to 126mm with freewheels, beyond this, I would go with a freehub.


Homebrew01
06-01-09, 11:35 PM
You could leave your hub at 126. When you put it on your bike, the qr will squeeze your dropouts to 126 temporarily. No big deal, 4 mm is pretty small. Just as many people do the opposite, putting a 130mm wheel into a 126 mm frame without coldsetting.

Soylent
06-02-09, 12:18 AM
Thanks for the quick replies. I saw that chart on Sheldon's site. The 134mm QR axle is what didn't make sense to me. Does that mean these hubs were 5 spd set up for 120mm spacing? Is the width of the 5 spd hub smaller than the 6/7 spd, or do they just use different axles. I wouldn't want to bridge from a 120mm hub to 130mm. I could squeeze it down but I would hate to have to unsrew the QR way out each time I removed the wheel and I don't really want to cold set the frame smaller.

Would an 8 spd freehub work with the 1983 SR derailleur? Maybe this is the way to go since I'm not completely hung up on keeping it all period correct.

Homebrew01
06-02-09, 05:05 AM
Thanks for the quick replies. I saw that chart on Sheldon's site. The 134mm QR axle is what didn't make sense to me. Does that mean these hubs were 5 spd set up for 120mm spacing? Is the width of the 5 spd hub smaller than the 6/7 spd, or do they just use different axles. I wouldn't want to bridge from a 120mm hub to 130mm. I could squeeze it down but I would hate to have to unsrew the QR way out each time I removed the wheel and I don't really want to cold set the frame smaller.

Would an 8 spd freehub work with the 1983 SR derailleur? Maybe this is the way to go since I'm not completely hung up on keeping it all period correct.

You wouldn't need to.

miamijim
06-02-09, 05:53 AM
Just squeeze the frame down to 126mm......

Soylent
06-02-09, 09:53 PM
Well, turns out that this is a 120mm 5spd hub. So much for eBay accuracy and my noobishness. I'm going to try and find a set of 8 spd C-record hubs.