Atom

WP 33

French Atom drum brake hub, times two, laced to vintage Mavic rims.  Two of these wheels were gathering dust in the back of Two Wheel Drive.  The bearings and brake action were smooth, and the wheels were mostly round. I repacked the hubs with fresh bearings and grease, and lightly sanded the brake shoes.  I trued and tensioned the wheels, and used one of my favorite bike tools to pull out some low spots in the rim– the Overland Rim-True Straightener formerly made in Grand Rapids, MI.

Nice hubs; in an era before disc brakes, an excellent alternative to rim brakes in rain, mud, or snow.  Geoff Apps outfitted many of his early bikes with LeLeu drum brakes.   Below, the hubshell acts as the braking surface.  Both hubs use nine 1/4″ balls per side.

Edit: Geoff Apps installed French LeLeu brakes to his early prototypes.  These brakes, unlike the offerings from Sturmey-Archer and others, featured a floating cam which powered both pads evenly.  This allowed more even braking and pad wear.  For a time, David Wrath-Sharman was manufacturing high-quality brakes with a similar design.  Read more about his hub brakes in this great interview on 63xc.com.

Also, an interesting discussion about hill-climbing bicycle geometry and some talk of hub brakes can be found in this thread.  Also featured, my new favorite fatbike which is fitted with very nice fenders and modern Sturmey-Archer hub brakes.

WP 36

The two brick colored surfaces are the brake pads, and can last for many thousand miles without service.  The brake is actuated by pulling a cable, which operates a cam and expands the brake ring outward.  The springs return the brake shoes to the rest position.  Ultimate stopping power is adequate, modulation is very good.  I sanded a light glaze off the brake pads.

WP 35

Atom, Fabrique en France.

WP 34

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14 thoughts on “Atom

  1. In my days of hub braked cars I am sure that you were supposed to leave the glaze on the pads but I’m equally sure that it will be back after a couple of uses :0)

    • It seems the glaze is probably mostly aluminum, which should build up again quickly enough. Part of the glaze on these pads was due to age, although I can’t say if it was a bad thing as I didn’t ride the wheels at all, before or after.

    • No. I’m working at a shop one day per week and one of my projects involves rehabilitating a pile of old wheels. Most are of decent parts that need some love, but will ride again soon. I grabbed these Atom/Mavic wheels first. There are some old Campy hubs in the pile as well.

  2. Hello; nice reflection on hub brakes.
    To be fair, I don’t rate drum brakes very highly, except for a particular French company called ‘Leleu’.
    Leleu produced an exceptional drum brake that really worked reliably, progressively and powerfully.
    The reason this particular drum brake worked so well was little known or appreciated; most people do not realise that this firm had come up with a unique design, which should have resulted in the world beating a path to its door.
    It did not, and Leleu disappeared, along with the genius it incorporated.
    No other drum brake comes anywhere close to a Leleu for performance.
    Actually, twixt thee & me, all other drum brakes are shite, although they are still much better than any rim brake.
    Nowadays I use Shimano’s ‘Roller Brakes’ ~ as good as Leleu, but for slightly different reasons.
    Rollerbrakes are not quite as smooth operating, however, they are available, cheap, virtually nil maintenance and, finally, because they run filled with grease, are completely unaffected by anything (except, perhaps, a small nuclear device). They are relatively heavy and have a small amount of rotational play, so what?
    The brakes I currently use were fitted in 2006 and I have had to do NOTHING to them, apart from a squirt of grease every year or two.
    Many other people say Rollerbrakes “…are not very powerful…”.
    I cannot account for this view. It is possible that I inhabit a parallel reality, or it could be that other people expect a brake to snap into action and instantly lock the wheel.
    This kind of brake action is not quite what you want when delicately balanced on a slippery off-camber ~ what you actually need is something very ‘spongy’, with oodles of predictable progressive braking action.
    This is my preferred brake action in any circumstance; it is what the Leleu brakes provided back then, and what Rollerbrakes do now, but which is generally regarded as ‘weak’ braking effect.
    Note that I do not refer to disc brakes. The reason? Regardless of their performance, they are relatively complex, vulnerable and expensive, as well as requiring a high level of maintenance.
    My Rollerbrakes? 50 smackers each, slap ‘em on, forget ‘em. Six year later, write this.
    Hope this is interesting.
    ~ Geoff

    • Geoff,

      Thanks for visiting. Last time I tread into new territory (650b ATB history), Graham was there to save me and help me find my way. Although I knew that you had been using hub brakes on some of your bikes, I had never taken one of these brakes apart. Now I can see that the “floating cam” mechanism seems highly valuable to operate the brake efficiently (even pad wear), and to gain a smooth transition in braking (modulation). The hubs from David Wrath-Sharman seem very, very nice. As I’ve been riding a Surly Pugsley for over a year in all conditions, I’d be curious about such brakes on a bike like that. I noticed that VeloBike was riding such a bike in some nasty UK conditions, with some very nice mudguards as well.

      In defense of rim brakes: they are light and their mechanics are transparent. Generally, disc brakes work fine, yet I find that their mechanics are out of reach to the average user, even with simpler mechanical models like the Avid BB7. As well, they are prone to feeling “grabby” in sensitive conditions, which is what I fear of “road disc” bikes. In all but the worst conditions, I have been happy with a well-tuned cantilever, but as I’ve seen, things can get pretty soggy in the UK. In such mucky conditions I would also be unhappy with the rate of pad and rim wear, as well as decreased stopping power.

      I’ve been curious about the Shimano RollerBrakes. I will have to look into it. I like cheap things, and 50 smackers sounds like a deal. Converting smackers to bucks…

      nicholas

  3. It’s cool you’re saving these old parts from the dumpster/recycling bin. Are the rims 27″? Rear spacing? Are you keeping these or just fixing them for Charlie?

    Thanks for the ‘Geoff Apps’ link. I hadn’t seen it before. His Flick’r album has some really interesting stuff.

    • Gary, Rims are 700c with some nice vintage Ritchey cross tires mounted with tan sidewalls. The rim rim had some unique aberrations, but I worked most of them out. As with any hub brake, the rim need not be perfectly round as it is not a braking surface. With the tires mounted, the wheels appeared functionally round.

      Above, a comment from Geoff Apps suggests that it was not S-A hubs that he was using, but the French LeLeu drum brake. It appears to have been an inexpensive product with some accidental genius– a floating design which actuated opposing pads equally.

      I have updated the article with some additional links.

      • Gently filed the the brake shoes…? steady on, old bean.. seem to remember that a couple of makes of older brake shoe used to have some small asbestos content to deal with the heat..
        i’d like to second the opinion of roller brakes. Rather under rated by the bike press, but with the slight drag that these brakes have, i can understand why.. used to have a couple of bikes fitted with a roller front and cantilever rims back. The roller brakes always brought me to a controlled stop whatever the weather..

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