re: [CR]Spoke tension wooden rims

(Example: Racing:Jacques Boyer)

To: classicrendezvous@bikelist.org
From: "Robert Schenker" <ris@schenkerdesign.com>
Subject: re: [CR]Spoke tension wooden rims
Date: Thu, 11 Jan 2007 11:33:37 -0800


At one time I went nuts over wood rims and built a number of pairs of wheels with them, riding them regularly for several years. I'll pass along what I remember learning.

First, you really must keep the spoke tension quite low, especially at first. Depending on climatic conditions, the rims will swell and shrink fairly dramatically. If the spokes are too tight and it's dry, when it gets damp you risk the rim de-laminating.

Obviously, it's also important to have very even spoke tension for the same reason. However, due to the organic nature of the material, this may not be so easy to judge.

The result is, in a period of prolonged dry conditions the spokes can become alarmingly loose, so much so that they tinkle and scrape when you accelerate or climb out of the saddle. Because the rim is resilient, unlike an aluminum rim, it is more than strong enough to work with no problems. The spoke noise (and along with that, the tendency for the rubbing to cause loosening) can be solved by tying and soldering--probably the original motivation for doing this.

When it's damp, the spoke tension will be mighty tight--hopefully just within the limits the rims can withstand--washers make a big difference here.

The wheels are very nice to ride on and very strong. I've hit major potholes with no problems. However, they are very weak if impacted laterally. I once had someone bump into the side of my rear wheel while we were looping around in a parking lot getting ready to start a ride. My wheel shattered into pieces.

Obviously, riding in the rain is a bad idea. Unless the varnish is very new and still covering the braking surfaces (only possible on a track machine) the rim can come apart rather quickly--been there.

The last thing is brake pads. The first time I did a real ride on my then new first set of wooden wheels, I returned down a longish downhill. At the bottom, my brake pads had melted away to almost nothing. It was shocking to see. In those days, the only workaround I could come up with was to round up some of the old asbestos filled red rubber pads that came on Universal or Weinmann (I forget which) brakes. These held up fine--although I may yet live to regret it. Nowadays, you might be able to use the same pads used for carbon rims, providing they can be fitted to your brake calipers. If all you do is flat rides, maybe this isn't too important--we don't have flat rides of any substance here.

Have fun, Bob Schenker Oakland, CA
> Am currently having some wheels built by my local wheelsmith. Early
> wooden rims that are in great condition, no warpage or cracks. I need
> some advice on the spoke tension - normal tension or possibly slightly
> releived. Straight 15 guage stainless, correct nipples and washers.
> These are for my '38 Bianchi and will see the odd spin down the road
> with my 90kg astride.
> Greg Softley
> Coffs Harbour
> Australia