Re: [CR]Rear axle replacement questions?

(Example: Events:Eroica)

Date: Mon, 18 Feb 2002 17:58:36 -0800
From: "Bill Bryant" <Bill_Bryant@prodigy.net>
To: "Roy H. Drinkwater" <roydrink@mac.com>
Cc: classic list <Classicrendezvous@bikelist.org>
Subject: Re: [CR]Rear axle replacement questions?
References: <000a01c1b850$c11bbec0$fabb56d1@Marta> <3C711629.1E64B35B@prodigy.net> <a05100330b896c4eb9f40@[192.168.1.1]>


"Roy H. Drinkwater" wrote:
> My questions are:
>
> 1. Are the Wheels Manufacturing axles a good replacement? I'd
> like to have some replacements on hand just in case, and they're
> available from QBC.

My experience with them is limited since I have a pretty good stash of Campy hub parts, but my impressions thus far are very favorable. Nicely machined and true--but I can't speak to their longevity with heavy riders over rough roads using a traditional 5 or 6 speed hub spacing. In modern road cassette hubs they seem quite good overall.

The one thing you will want to be sure of is to get a replacement axle with the milled keyway. Modern hubs tend not to use them to save production costs, but classic Campagnolo hubs did to help keep the bearing adjustment from creeping over time. Also, be sure you are ordering the appropriate thread. The Campy units were, if memory serves, 10x26, while the French and Japanese ones are 10x1 metric. (If you can't get one with a keyway, it isn't the end of the world since hubs without this seem to hold their adjustment pretty well most of the time. However, the older, more time-consuming method makes a slightly more reliable axle assembly, IMHO.)
>
> b. The front axles are listed as 110mm; 100mm spacing + 5mm each
> dropout, but the rear axles are longer. Are rear dropouts wider than
> fronts? Would they be 5.5mm? And therefore, 126mm spacing would
> have a 137mm axle (126+5.5+5.5)?

Yes, when discussing axles, the common measurement is actually the space between the dropouts, not the actual overall axle length. So, I measured some NOS Campagnolo hubs at: Front: 100mm over locknut; 109mm total length, or 4.5mm sticking out from each locknut Rear: 126mm overlocknut; 136mm total length, or 5mm sticking out from each locknut For a five speed hub, subtract 5mm from the gear side spacer and axle. (Depending on the freewheel and frame clearance, 6mm could be subtracted in many instances and this will help with slightly less spoke dish.)

I measured some new, unpainted Campagnolo #1010 dropouts and they were: Front: 5.5mm width Rear: 7mm width

Importantly, don't assume all Campy hub parts are identical despite the same parts numbers in the Campy catalogs. The axle lock nuts, aluminum spacers and toothed washers were available in several widths so overall axle and freewheel spacing could be fine-tuned for precise wheel spacing between the dropouts. Probably not a big concern for most individual owners, but when you are lining up many sets of race team wheels then the shifting must be identical on all the bikes. Not for indexing (which was still off in the future), but more for being able to get into low gear but not going into the spokes, or on the other end, not shifting off the outer cog after a wheel change. This was one small, but crucial way Campy race support with parts was superior to all other brands by a mile.

Anyway, if you are fine-tuning your axle set-up, the toothed axle washers were made in .5mm, 1.0mm and 1.5mm widths. For shifting and wheel dish reasons, it is important to keep the same set-up after any hub overhauls. If you swap things around, things may not line up exactly as they did before (depending on what items are on the axle to begin with.) Keeping the gear side cones and spacers intact and just doing all the disassembly from the non-gear side is the time-honored way to keep things straight. Anyway, no reason to undo the gear side unless a cone replacement is needed. Also, when you have a rear hub apart, it is a good idea to carefully inspect the rear axle for cracks with a magnifying lens. Sometimes you can spot something starting before it breaks. Inspect the axle just inboard of the gear-side cone.

Similarly, if your front hub is either too loose or tight in the front fork, try measuring the distance between locknuts and then the distance between dropouts. Some fiddling with different width washers might get a better fit.

Also, it goes without saying that using a good axle vise is mandatory for best results. IMHO, the Campy unit can't be beat for holding things securely without hurting the threads. Worth every penny.
>
> III. Do Record and Nuovo Tipo rear hubs both use 10mm 26tpi axles?

Yes, the axles are interchangeable (am not sure of the cones, though... alas, time has been eroding the details)
>
> four. Can an axle be cut or ground down to the proper length
> without weakening it?

I didn't do this too often, but wouldn't worry about it. Where you are cutting is out at the end, while the place axles break is immediately inboard of where the cone assembly sits under freewheel threads. I can't recall seeing them break anywhere else.

For this operation, I'd use a hacksaw, followed by a quick trip to the belt sander (or lathe) to dress the cut end before I tried ~grinding~ off 5mm of threads--yow. Things will stay a lot cooler and the noise level is lower by far. For a straight, fast cut, just stick the desired excess out of an axle vise, then cut it off using the vise to keep the saw blade perpendicular to the axle. (I use an old "cheapo" axle vise for this operation so as to keep the Campy unit in good shape.)

Good luck with your project, it's all straightforward stuff and you'll no doubt stay out of trouble. For best results, your metric calipers will be as important as cones wrenches and axle vise.

Cheers,
Bill Bryant
Santa Cruz, CA