Is it possible to alter a rear Campagnolo Hub? Advice please.

[Fifthgrace]

Appreciate some help with this: I bought a nice pair of clincher wheels: Ambrosio Durex Servizio Corsa rims on Campagnolo (Chorus?) Hubs. A 6 speed Falcon cassette/freewheel (haven't removed it yet as needs a unique tool) was fitted and I thought the rear OLN would be c.126mm. However, it's coming in at 129mm and I'm not really happy with the forces it applies to the frame I have. Is it that the hub is really a 130mm? Can I alter the hub/axle so it better fits a 126mm? Pics attached for reference. Thank you.

 

[Midlife]

After my time but is that a freewheel ? Maybe the extra alloy bit on the non drive side comes off ?

 

[Guinessisgoodforyou]

@benjabbi @bikeworkshop

 

[Fifthgrace]

After my time but is that a freewheel ? Maybe the extra alloy bit on the non drive side comes off ?

Yes probably a freewheel but not yet removed. Not sure on the alloy bit- it rotates freely.

 

[pigman]

Looking at that alloy cone spacer on the left, I'd say the left side can't be reduced.
So you could take axle washers out of the right but any freewheel you use will have to be really narrow

And not forgetting that the wheel will need redishing

 

[onegoodbike]

Hi,

it looks to be a mid to late 80s Campag C-Record rear hub, it should have an OLN measurement (rear spacing) of 126mm, according to the velobase website.

The alloy part on the non-drive side is the dust cover for the bearing assembly, it's removable for adjusting the bearings with an expensive proprietary tool (see ebay), or more carefully with a wide flat-bladed screwdriver used slowly to lever it away from the body.

It looks to be an example that is threaded for freewheels, once the freewheel is removed there should be some spacers that can be removed from the drive side axle assembly allowing you to bring the spacing back to the 126mm you require (although unlikely, it may be possible that there is also a spacer(s) on the non-drive side, these would be obvious once the dust cover is removed).

Once you have reduced the rear spacing you may need to slightly re-centre the bearing races so that the amount of threaded axle exposed is equal on both sides. It is worth checking this new axle measurement to make sure it will still clamp correctly in the rear dropouts, although effectively adding 1.5mm to each side should not be a problem if it's still the original axle.

Hope this helps.

Cheers Matt

 

[Fifthgrace]

Hi,

it looks to be a mid to late 80s Campag C-Record rear hub, it should have an OLN measurement (rear spacing) of 126mm, according to the velobase website.

The alloy part on the non-drive side is the dust cover for the bearing assembly, it's removable for adjusting the bearings with an expensive proprietary tool (see ebay), or more carefully with a wide flat-bladed screwdriver used slowly to lever it away from the body.

It looks to be an example that is threaded for freewheels, once the freewheel is removed there should be some spacers that can be removed from the drive side axle assembly allowing you to bring the spacing back to the 126mm you require (although unlikely, it may be possible that there is also a spacer(s) on the non-drive side, these would be obvious once the dust cover is removed).

Once you have reduced the rear spacing you may need to slightly re-centre the bearing races so that the amount of threaded axle exposed is equal on both sides. It is worth checking this new axle measurement to make sure it will still clamp correctly in the rear dropouts, although effectively adding 1.5mm to each side should not be a problem if it's still the original axle.

Hope this helps.

Cheers Matt

Thanks for the info Matt, I've purchased the FR7 removal tool for the Falcon Freewheel and will look to take it from there...

 

[Fifthgrace]

Just an update on this: I've removed the freewheel and can now measure the axle which is definitely set for 130mm, despite it running a 6 speed freewheel. I'll remove the dust cap on the non drive side, I'll then either use a replacement 134mm axle (for 126/7 OLN) or cut the current one down after using reduced spacer(s) and re-setting lock nut positions. If that doesn't work, I may have to run with the wheel slightly off centre line.

 

[bikeworkshop]

These axles are usually a 9.5mm? thread not standard, so unless you have a 126 campag axle of similar period it will be easiest to cut 4mm off the existing.
You should then be able to reduce the spacers each side by 2mm, giving you the right end result.
The NDS does look a bit close, but I'd say these hubs are often 126 so should be fine

 

[Fifthgrace]

@bikeworkshop , Yes thanks- 9.5-10mm thick, hollow Campagnolo axle. So far I've managed to remove a 2mm spacer on the non drive side, and have just ordered an 11mm to replace the 13mm spacer on the drive side, Once I've fitted that, I'll cut 4mm off the current axle. Threading is 26tpi (not the modern standard which is 1mm).