126mm dropouts and 7-speed campag: obsolescence issues

Sgt Pluck · Post by **Sgt Pluck** » 11 Aug 2007, 3:58pm

Half the posts here seem to be about drivetrain compatibility issues so apologies for adding another one...

I recently bought an old 531C road bike (early 90's?) which is in lovely condition apart from the rear hub, which has badly pitted cones and is definitely on the way out. The frame has 126mm dropouts and it is fitted with a 7-speed campagnolo freewheel, I've had a trawl on the internet already and I can't find any reference to 7-speed campag cassettes whatsoever. So clearly getting a new hub or wheel that will work with the derailleur and integrated gear-shifters is not going to be straightforward.

Any suggestions on how to keep this bike on the road? It's probably not worth spending too much money on it, and I'm prepared to accept I may be on a hiding to nothing, but it seems a shame to give up on it. If I could find any hub/cassette combination that would work with the existing derailleur and shifter I'd be laughing. Failing that, I'd contemplate replacing most of the groupset but then there would be the 126mm dropouts to contend with.

Thanks,
Paul

reohn2 · Post by **reohn2** » 11 Aug 2007, 4:10pm

Later hubs are 130mm but will fit 126mm frames if you are prepared to just spring the dropouts to get the hub in,I've just had a pair of wheels built that are 130mm and was surprised how easy the rear one went in the 126mm d/outs on my frame.
As for the Campag 7sp thingy I've never owned anything Campag so can't help with that part of the question.

Post by **Mick F** » 11 Aug 2007, 9:01pm

My Mercian Vincitore is 21 years old this summer. It was built with a 126mm rear end.

I've been using a 130mm "modern" Campag hubs for some years now. So what? It just fits ok! Springs a bit, but ok nonetheless. It's only 4mm.

drossall · Post by **drossall** » 11 Aug 2007, 11:09pm

Don't you just need a screw-thread hub? Either a new one, which will probably be 130mm and mean springing the drop-outs a bit, or a second-hand?

Alternatively, especially if the hub is Campag too, you should be able to replace cones, bearing surfaces, the lot. Try Baker's Bikes at Bishops Stortford or Mercian in Derby.

MartinC · Post by **MartinC** » 13 Aug 2007, 4:14pm

You need to get some 7 speed hubs of almost any description. If they're threaded hubs then you can get 7 speed freewheels to fit - I'm sure I've seen Spa Cycles and Byercycles advertising them. 7 speed spacing is the same whether it's Campag, Shimano, Sachs or whatever. If you can get some Campag 7 speed cassette hubs then you're still OK, you can still get 8 speed Campag cassettes - just remove 1 sprocket and spacer and you're OK, 7 and 8 speed Campag spacing was the same. 7 speed Shimano hubs will work too because 7 speed Shimano cassettes are still available and the spacing is the same.

Of course if the gears aren't indexed then any 126mm hub and any 5,6 or 7 speed freewheel or cassette will work

Handlebar Dave · Post by **Handlebar Dave** » 13 Aug 2007, 4:28pm

I once had a second hand 531pro frame that the previous owner had sprung to take a 130 axle (from the original 126). Unfortunately after a few years, the frame cracked across the chain stays just past the brace. The cracks on both sides started from the inner face and lead me to conclude that the frame had cracked as a result of the springing.

However 531pro was notoriously brittle and you are probably fine springing 531C.

pliptrot · Post by **pliptrot** » 13 Aug 2007, 5:21pm

If the system is indexed then the following may help;

126mm screw on hubs can take 7 speed freehweels in most cases, but the Campag hub/ screw on 7 speed freewheel combination is a bit tighter (and with a Sachs 7 speed block the smallet sprocket will be very close to the drop out, making wheel removal difficult and you can't use that sprocket). My 126mm Campag hub/Shimano 7 speed freeewheel combo works perfectly with Campag 8 speed ergo levers (and Campag derailleur), and also worked with Shimano 7 speed d/tube levers and rear mech.

7 and 8 speed indexed systems use 5mm sprocket spacing, so if you end up with an 8 speed (invariably 130mm OLN hub) system the indexed gearing should work.