Sturmey Archer Drum Brake - initial thoughts

[KneesUp]

I've been toying with getting drum brakes on my bike for some time, largely because

a) I get annoyed at my cantis squeaking in the damp
b) I get annoyed by my cantis not working as well in the wet
c) I am tight, and I don't like braking wearing out my rims, and I really don't like the resulting black gunk, especially in winter
d) I like the idea of a brake that doesn't rely on the wheel being totally straight, especially on a bike used for all sorts - but my frame has no disc mounts
e) They're unusual, and if I'm honest that appeals

So I now have a Sturmey Archer X-FD (70mm) on my front wheel - I wanted an XL-FD (90mm) or even an XL-FDD (90mm with dynamo) but the FD was a (secondhand) bargain so I picked it up to see if I actually like the feel of drums. I thought I'd post my initial thoughts in case anyone else has been thinking about it.

It isn't massively heavy - certainly in the hand it doesn't feel significantly different to the 32-spoke generic Specialized rim / Deore LX wheel that I took off once it's got a tube and tyre on. Of course it does weigh more I suspect, but it's not an order of magnitude such that when you pick it up you think 'chuffin 'ell" Of course I've been able to remove the cantis too, so there is a weight 'credit' there. Overall it's heavier - it's got more brkae outer, and the clamp on the fork - but the rim is lighter, and the hub is not massively more than the other hub plus cantis. I guess the larger XL-FD will be more, and the XL-FDD more again. As a bonus, the barely used Sturmey hub runs a lot more smoothly than my "I-really-should-service-them" old hub was.

Fitting was fairly simple -all I got was the wheel and hub and the adjuster. The adjuster is really important - you can't fit them without one as it anchors the cable to the reaction arm. I didn't get a proper Sturmey clamp, so I've used a jubilee clip and a it of inner tube to clamp it to the fork leg. I got one with a wing-nut arrangement so it's easier to slacken off should I need to get the wheel off. Fitting was just a case of putting in a new cable (because the old one was too short - it has to go down the fork leg) with a full length outer. Ideally you use Sturmey's own double ended cable, but they seem to be 90cm long, which is 20cm too long for my bike. Plus I couldn't find one locally to buy. The adjuster came with a little metal cylinde with a hole which sits in the bit the cable pulls, so I just used a pinch bolt to hold that in place, because the pinch bolt didn't fit in the recess the cylinder bit is supposed to go in. Sturmey do their own specific correct-sized pinch bolt for this but again, nowhere local has them, and I was too impatient for the internet to deliver.

Anyway, it took maybe half an hour to fit, but 20 minutes of that was fiddling about trying to get something to clamp on the end of the cable - I tried a 'solderless nipple' first but that wouldn't hold under a full braking load - if I'd had the proper Sturmey part it'd all have been done in 10 to 15 minutes.

I've ridden it to work this morning, and first thoughts were it didn't feel any better than the cantis. However, commuter traffic being commuter traffic I had to hit the brakes hard at one point this morning and I stopped pretty quickly. It's good to know that the performance should be the same regardless of the weather too. I guess it may improve as the shoes bed in (if they're not already) and a 90mm XL-Fd might be better, but it's perfectly fine now. I have read that compressionless cables make them better - mines on boggo Clarks outer but I won't be rushing to upgrade. I've seen elsewhere that people have bent forks using compressionless outers, but my forks are chunky steel MTB ones so I think they'd be ok.

So there you go - initial thoughts are it's quite good and will be the same regardless of the weather, hopefully. The shoes might not be bedded in yet, and it might be even better with compressionless outer. It's not loads heavier, and hopefully will be largely maintenance free. I'll update if anything changes.

 

[KneesUp]

Update - the damn drum is squeaking! One of the main things that annoyed me enough to get rid of the cantis!

I've not had it apart since I bought it, and it was secondhand, so I'll get the cover off and give it a clean at some point. It only squeaks slightly just before you stop, so it's not as bad as the constant squeal of damp rim brakes. Yet!

 

[amasidlover]

I had an XL-FDD until I changed bike to one with disc brakes. For me the braking in the wet was the big advantage (that and the built in dynamo) - braking in the dry was much the same as a decent rim brake.

 

[Drago]

degrease it and rub the working surfaces of the shoes with 800 grit wet and dry and slightly soapy water.

I have a motorcycle handbook from the 1920's. There recommended cure of squeaky brakes was a dollop of grease in the drums! I kid ye not!!!

 

[Globalti]

I used to ride a Puch Maxi moped, which had drum brakes probably very similar to the SA brakes described. They were a nightmare to maintain because the pads wore out fast creating lots of dust, which made them squeak and because when they got hot, grease from the wheel bearing contaminated them causing them to lose efficiency and squeak even worse, stopping the bike with a judder and a horrible squawk. I think of all the brakes, drum brakes are probably the worst ventilated and the most prone to overheating. Oh and the brake dust can't escape as it does with a disc or a rim brake. The drum brakes on the rear axle of our Land Rover 90 had the same shortcomings with accumulation of dust, especially after wading had filled them with muddy water.

 

[Smokin Joe]

I agree with everything @Globalti said.

I've had drums on motorcycles and cars and I wouldn't touch them on a bike. They are simply not a patch on discs in either performance or ease of maintenance.

 

[Globalti]

Here's a pic I found in a mag called Mountain Bike Monthly, which failed after just a couple of editions, showing a very early attempt at a disc brake. Even this would be preferable to a drum.

It has a massive swept area; I wonder how the crude fixing system stood up to the torque the brake must have experienced?

 

[KneesUp]

As mentioned in my opening post though, my frame has no disc mounts, and wasn't designed with them in mind, so would need reinforcing on the rear triangle and replacement forks (with disc mounts, in non-suspension corrected 26" wheel with a 1" headset ...)

I've read many reports of SA hub brakes requiring almost no maintenance - a bike is a lot lighter than any motorcycle, don't forget, and with me on board is definitely a lot slower - so the demands are much less. I took the cover off the hub last night and greased the pivot - it took about 5 minutes including taking off and remounting the wheel. I suppose if I had brake cleaner I could have cleaned it out in another few minutes, but it looks barely used - I think my squeaking might be because the pads have glazed slightly, so I'll get something to rough them up a bit.

I've also read many reports of squeaky discs, disc pads lasting an afternoon, discs that seize, discs that are buckled, callipers getting stuck and all sorts. All I've ever seen abotu SA hubs is that the pads will last, essentially, as long as you want, and that you need to clean it out every few thousand miles (and as above - it takes basically no time) We shall see though

 

[tyred]

The Sachs drums on my post office bike work like a dream. I can definitely see the appeal.

 

[Drago]

Sachs drums can indeed work well. The shimano roller drums can work well, and some very niche MTB builders like them for their excellent modulation and lack of propensity to lock unexpectedly when grabbing a handful in a panic. Back when Highpath were making very expensive Cleland style MTB's they had their own bespoke drum brake set up designed by Dave Wrath-Sharman, and they were superb performers.

Drum brakes could be a low maintenance, all weather, relatively high performance option, but very few people/firms have gone to the effort of developing them to an effective degree. Shame.

 

[fatjel]

My trike has SA drums , which work OK , they don’t squeak either.
The front left one did stick on once down a fairly steep hill and took over steering responsibility
That was interesting .
Fitted some return springs and the terror hasn’t returned

 

[stewie griffin]

Update - the damn drum is squeaking! One of the main things that annoyed me enough to get rid of the cantis!

Here are my experiences with 70mm S.A drums.

Just over a year ago I bought a restored bike (Cleland) that hadn't been set up or ridden fitted with N.O.S Sturmey Archer drums, they had always appealed to me for the same reasons you mentioned in your first post.
But, despite decades of drum brake experience on old British bikes & foreign cars (I have a few drum motorbikes & run a car with drums all round) non of the tricks would stop the things intermittently squealing or juddering, it drove me up the wall, every time I tried something new they'd maybe behave for a ride then next ride play up....

The S.A drums have a major flaw. All drum brakes I've ever worked on previously have some kind of "float" to let the shoes center or balance, not so with the S.A back plates, fixed pivot & cam, even if you manually balance the shoes by marking & removing material it's only a matter of time before the leading shoe wears more than the trailing & you're back to an imbalance, one shoe getting more force than the other creating all kinds of annoyance.

I cannot stand things not working correctly, noisy brakes pretty much top my list of things that I can't stand, so it was either find some new brakes/wheels or try a modification, the mod won because I had nothing to loose, I was not prepared to carry on having my rides destroyed by brakes playing up.

With info found on the web of similar mods I made the pivot "float", it only needs a mm or two & all becomes harmonious & happy! After lots of miles of silents braking I've forgotten about them, just what I wanted in the first place!
They're not super Powerful, I'd describe them as adequate, similar to canti's.

Below is what I did, a bit involved but worth it.

The back plate with the steel pivot bush removed (press fit) & the hole elongated.

Pivot bushing welded to a plate, slotted hole fits over a threaded screw to locate it but allow movement.

With nut on the thread to apply a little friction (not tight) & fitted with the brake arm.

Now the pivot is free to center itself & balance the forces applied to the shoes equally.

 

[Drago]

You have a Cleland? Fantastic! I love the Clelands, Highpaths and English Cycles derivatives.

 

[Serge]

My trike has SA drums , which work OK , they don’t squeak either.
The front left one did stick on once down a fairly steep hill and took over steering responsibility
That was interesting .
Fitted some return springs and the terror hasn’t returned

Damn, I just coughed hot tea out of my nose after reading that.

 

[simon.r]

The ex TNT bike in my avatar has SA drum brakes front and rear.

My experience is that they work well enough to slow down / stop a heavy bike and require virtually no maintenance,.

I ride to their limits (i.e. not fast and planning ahead as much as possible).

I’ve not had to do a full on, real-life, emergency stop from high speed on the bike, but given what I use the bike for and my riding style on it I suspect I never will have to.

Horses for courses.