Drum Brakes?

[Duchess]

Anyone ever use drum brakes? I'm going to be converting an old hybrid to electric. Whether I can wait for the BO or not is to be determined (I'm trying to content myself with parts gathering and diagramming the electrical), but I'm thinking cantilever or V-brakes are going to be a little weak at least on the front wheel for a "1000W" mid mount (more like 1700W with a full charge 52V pack). I can't upgrade to discs with a 1" fork, so I'm thinking a 90mm SA drum. Reviews I've read about the power are pretty good, but I was wondering if anyone here had any experience with them.

 

[Chainmaker2]

I love my front drums, they are fantastic!!..the stopping is smooth and sure!!!!..every motorized bicycle I've built has had a front SA drum...wouldnt build a motored bike without one. I've used them only cruisers as well , but not "standard"

 

[JA331]

I have SA drum brakes on my red menace. All good. Smooth and more braking power than i needed but I had to build a set of wheels and the cost was reasonable on ebay. You’ll be happy with them.

 

[JA331]

 

[sandman]

I have been looking @ this 50s Town and Country and contemplating making a offer just for the wheel . I have a Schwinn Cruiser Supreme that I put a set of SA drum brakes from another tandem and love them .

https://www.facebook.com/groups/370077396500469/permalink/1766809920160536

 

[Duchess]

Wow, that was fast! Perfect. I don't expect I'm going to be running this thing at speeds it can achieve (well . . . not often), but definitely higher than my average cruise speed and I need something more effective than upgrading cantilevers to V brakes. Ordered a 90mm SA. Thanks everyone!

 

[Starnger]

Drum brakes are great, but prone to overheating, unlike disc brakes. If you are building a heavy electric bike the drum brakes could possibly bake. I would still try to switch at least your front to disc, and use roller or drum as a rear brake. Why is it a problem to use 1" fork with the disc brake? Is it connected to specifics of your build?

 

[Duchess]

Drum brakes are great, but prone to overheating, unlike disc brakes. If you are building a heavy electric bike the drum brakes could possibly bake. I would still try to switch at least your front to disc, and use roller or drum as a rear brake. Why is it a problem to use 1" fork with the disc brake? Is it connected to specifics of your build?

From spending hours looking, I don't think 1" 700c disc forks exist (if they do, they're apparently super rare and would probably not be new). It's only a more recent thing that road bikes and road bikes with wider tires gravel bikes have moved to disc and they're all 1 1/8". I can find them in 26", but those are still not common. While I was pleasantly surprised by the disc adaptor I used on the rear of Cyclops (slow cruiser), I would never trust it on the front. So, while I'd prefer discs, I'm going to tell myself not to worry about fade as I've always been easy on brakes and I'll still have the rear rim brake (with the battery weight over it). It's also cheaper since I don't have to buy a fork on top of building a wheel (though, at this point, acceptable pre-built disc wheels are probably cheaper than building a drum, so the difference might not be that bad). Of course, if I found a disc fork and it was a reasonable price, I'd have gone with that.

 

[Verrt]

If you're in the 120-150 price range monark style springers and chopper/triple-clamp forks can both be obtained in 1" threaded with disk brake tabs.

 

[Verrt]

Also found this nasty lookin suspension fork on ebay. 1" threaded.
$80 bucks, plus a sneaky $40 shipping kidney punch
https://www.ebay.com/itm/NEW-ORIGIN...N-FORK-1-INCH-THREADED-IN-SILVER/393022770760

 

[JA331]

I haven’t experienced fade with my SA drum brakes on the red menace and i’m 220lbs and been fast down a few steep hills. It weighs about 35lbs which is 20lbs lighter than the Trek allant I converted for a friend with a Dillenger electric kit (not as powerful as the kit you want to use). The Allant has v brakes and pulled me up easily at 30+ mph downhill. It depends on how fast you intend to go and how hard and long you are on the brakes before you get fade. A disc setup would be best and the reason most electric bikes have them.

 

[Starnger]

From spending hours looking, I don't think 1" 700c disc forks exist (if they do, they're apparently super rare and would probably not be new). It's only a more recent thing that road bikes and road bikes with wider tires gravel bikes have moved to disc and they're all 1 1/8". I can find them in 26", but those are still not common. While I was pleasantly surprised by the disc adaptor I used on the rear of Cyclops (slow cruiser), I would never trust it on the front. So, while I'd prefer discs, I'm going to tell myself not to worry about fade as I've always been easy on brakes and I'll still have the rear rim brake (with the battery weight over it). It's also cheaper since I don't have to buy a fork on top of building a wheel (though, at this point, acceptable pre-built disc wheels are probably cheaper than building a drum, so the difference might not be that bad). Of course, if I found a disc fork and it was a reasonable price, I'd have gone with that.

True so, i've checked now and found out most of the forks i've thought about while writing that are either 26" or 700c 1-1/8. Well, maybe the welded on disc brake tab can do then. Otherwise i think you may be safe with a bigger drum brake designed for a tandem bike.

 

[mikeeebikey]

Be very aware which drum!!! I have a copy of an Atom, more a suggestion to slow or stop!!! Looks good!

 

[Duchess]

It's a SA 90mm. The reviews seem to say they're almost as good as discs when bedded in and some of those are from use with ebikes. The 70mm seems to be pretty much universally appraised as about equivalent to rim brakes. Of course, I don't know what discs they mean in the former case, but it should beat the rim brake option I otherwise have.

I totally forgot about the Monark repro forks, but I don't know if I trust that suspension or build quality for higher speeds. I thought of 26", but would rather stick with the 700c. If this turns out to be a huge fail, I'll revisit this option, but I already ordered the hub, so I'll find out.

Of course, if this whole thing just ends up being ridiculous, I'll look for a decent used hardtail disc mountain bike and move the drivetrain over to that. It's just that I love the geometry of these early '90s Giant Innovas and thought one might be fun to convert to electric.

 

[Verrt]

I totally forgot about the Monark repro forks, but I don't know if I trust that suspension or build quality for higher speeds.

I've seen beefy monark style forks made specifically for ebike cruiser market, but then you're looking at the $200+ range.

 

[jamesdart]

I put front and rear drum on a klunker build and couldn’t get them to stop. it sits there unridden. I feel like the cables I used stretch too much

 

[JA331]

I put front and rear drum on a klunker build and couldn’t get them to stop. it sits there unridden. I feel like the cables I used stretch too much

Not sure what brand of drums you have. I had a similar issue with a rear roller. I changed the lever to a long one like you would use on a old style caliper brake and it now works really well. I’m using the same levers on my SA drums too.

 

[Duchess]

I read that housing flex is a problem. People who used the aluminum section housing reported good results.

 

[clamdigger]

Uber reportedly put $200 million into Jump Rental bikes. Now the wheels are being sold cheap. Here is a deal on a used SA XLRD 3 speed w/ drum brake, no axle nuts or related install parts https://jag35.com/collections/jehus-deals/products/26-bafang-rear-wheel-tire-w-tektro-disk-break . They have the used front wheel with hub motor for sale also.

 

[Lem Sportsinterviews]

Uber reportedly put $200 million into Jump Rental bikes. Now the wheels are being sold cheap. Here is a deal on a used SA XLRD 3 speed w/ drum brake, no axle nuts or related install parts https://jag35.com/collections/jehus-deals/products/26-bafang-rear-wheel-tire-w-tektro-disk-break . They have the used front wheel with hub motor for sale also.

I was actually planning on getting this exact hub for my motorbike build, and here's an entire wheel for a third of what the hub alone would cost. I hate you for posting this and making me spend money.