Shahmatt

I am planning to build a Python recumbent bike. Possibly start work next year so just researching now.

I was considering using Shimano roller brakes on both wheels as they seem simpler to implement with less welding needed and stronger stays.

Other advantages could be better dirt resistance compared to disks and also the wheel rims will be spared.

But how about braking ability, performance and maintenance? Online reviews seem sparse on the topic. I found one comment saying that the brake levers feel more spongy to actuate, but that in itself does not seem like a con.

So i am looking for some opinions. Any experiences on this brake type is appreciated. Thanks in advance for any help.

rhenning

They were a fad for a short time and went away I would guess for a reason. Roger

HillRider

I did some searching and the consensus is they dissipate heat poorly and are unsuited for sustained braking in mountainous terrain. If you plan to tour with your bike and have long downhills to deal with, they aren't the brake of choice. If you are doing city/town/commuting riding they should work fine.

As Roger noted, you don't see or hear about them much anymore and there are probably a couple of good reasons.

Wilfred Laurier

Two problems with them: (1) Lack of modulation (they go from slightly slowing the bike to completely locked up and skidding within a mm of lever travel), and the front brake is generally built with a 'power modulator', which is just a spring-loaded mechanism on, or flex somehow built into, the actuator arm that greatly limits the maximum amount of braking force... like limits it to the point that the brakes are pretty poor. I have thought about trying to modify a Shimano front hub to remove this feature, but decided it was not wise (see #1 ).

Shahmatt

Yes I do know about the heat dissipation problem. But i found that Shimano manufactures different models depending on the demand. Brakes expected to take on more loading have larger fins and hence larger heat dissipation ability.

Also it looks like these are being designed for the ebike market mainly. Since ebikes are heavier and faster would that not mean the brakes are reasonably effective?

Shahmatt

Thanks for the info. I did not know about the modulation problem.

I guess rear roller brakes do not have modulation, but on a regular bike hard braking on the rear would not be useful.

But how about using a rear brake up front in a weighted FWD recumbent configuration like a Python. Would it be more meaningful then do you think?

Wilfred Laurier

While a roller brake on the front of a recumbent may not have the danger of immediate faceplants* like an upright bike, they just are not very good brakes. Their only advantage is consistent (consistently bad TBH) performance in wet conditions, while rim brakes, which were the only other option when roller brakes were first introduced, are more affected by wet conditions.

*MAY not have that danger. I have little experience with recumbents and none with the Pythons so I can't say. I wouldn't bother, though. There are too many other good options. When roller brakes were first introduced, V brakes weren't even available. There is no reason for them to exist anymore.

Also, regarding your earlier point about the strength of stays needed for different types of brakes, roller brakes will put essentially the same force on the stays as discs under the same braking force, except roller brakes have such poor modulation that they will likely be putting more load on the stays more often. The bike will also be harder to control in corners and on loose surfaces.

Shahmatt

I see. That's a good point about the stays taking on sudden hard forces due to the modulation problem. One problem leads to another as it were.

dabac

I’ve never had them on a ”keeper” bike. But I’ve built and flipped bikes with them. That’d be bikes that got to see some commuting action before I’ve sent them on.
Where roller brakes shine is in weather independency. Even drum brakes can produce an occasional squeal/squeak if weather suddenly turns very humid(and a little cold). The rollers, never a peep.
As for upkeep, rollers are easy. They’ll ”need” a squirt of high-temperature grease perhaps yearly. Given that, they’re supposed to last indefinitely.
Drums do have a definite wear, although slow.
WRT stopping power, I find them average. They take more hand effort than (mechanical) discs. Let’s say about as much as noname V-brakes. But it’s consistent.
Modulation or lack thereof never bothered me, and I ran ”clean” cabling. No special pieces to tweak performance.
It might be that I’m the odd one out. I’ve used V-brakes with Canti levers w/o being particularly troubled by that.
Heat dissipation - can’t help you there. Precious few of the bikes that pass my hands gets taken touring. And my regular commute doesn’t have much in the way of descents. They are available in a version supposedly better at it though.

WizardOfBoz

Check out Sheldon Brown's clear assessment here: https://sheldonbrown.com/rollerbrakes.html

Sounds like for a transport bike in an urban environment without any steep or long descents, they have some advantages.

Not suitable for areas with long and/or steep hills. Nor for cargo or tandem bikes. The killer for me is that they add a tiny bit of drag even when not applied.

hokiefyd 

This may vary regionally but, at least in North America, the e-bike market is almost exclusively using hydraulic disc brakes. Some of the less expensive varieties will use mechanical disc brakes. I don't know of any new e-bike that comes with rim brakes or roller brakes. I'm sure there are conversions out there that exist with these brake types, but I would say they're in the vast minority.

WizardOfBoz

That seems to be exactly opposite Sheldon's take on the matter. His point was that they don't handle heavy duty cycles well. Curious to know what factors in roller brakes are superior to disk brakes?

GamblerGORD53

There is supposedly drag from the grease, more when cold.
My 90mm SA Dyno drum brake has NO such drag or upkeep or adjustment thru 25,500 miles. One sealed bearing went at 17,000 miles. After my first tour in China, I did find some mud splatter had seeped in and settled in the corner. If anything, dirt makes it stop better. It acts like ABS braking, Ok with me for the front. I had a really poor rear caliper that trip too. I now have a Spyre disc on the back Rohloff that will easily lock the wheel.

Shahmatt

Would not SA also use grease in some way? If so I guess the quality must be better.

Which begs the question if one were to use a thinner grease for Shimano's brakes would the performance improve? Sort of like dunking the IGHs in oil as opposed to the prescribed expensive white stuff (tested by Dan Burkhart).

WizardOfBoz

I think the point is that roller brakes are constantly bearing against hub surfaces. Barely, when not in use, and very intensely when applied. I suspect that the pressures involved require grease, not oil. Hence roller brakes are always gonna have friction. Drum brakes don't share this design issue.

sweeks

I put a Shimano roller brake on each of two Dahon folding bikes to remediate the wear the rear rims were suffering from. These bikes have Nexus hubs, which have an interface with the roller brake built in. The wear problem was immediately a thing of the past.
One of these modules has a large heat sink which resembles a disc brake (and confuses some people). The other is the "basic" version and has no heat sink. I have never noticed either getting appreciably hot.
There is a special "roller brake" grease which is supposed to be injected through a port at some intervals. I do it once a year. I have not noticed any additional drag, though there must be some. Same is true of the internally-geared hubs; no noticeable drag.
As to performance, neither of my roller brakes is the least bit "grabby". In fact, although I am able to lock up the rear wheels, it takes a real handful of lever. I think for this reason the roller brake is really only suitable for a rear wheel application.
YMMV

JoeKahno

Both of my Bridgestones have them on the rear. They get grabby when they need lube. If you over lube them or adjust them too tight they drag. Basically they're an independent coaster brake that is cable actuated, with the same advantages and disadvantages. Mine don't feel as "crisp" as the rim brakes but the cables are old and should probably be replaced. Either of them will lock the rear wheel and neither of them gets to that point unpredictably. On the pro side, I recently took a rim hit. A glancing impact with a rock bent the bead pretty sharply over an inch and a half stretch. I managed to straighten the steel rim well enough to run true and not show obvious damage. If I were using rim brakes I'd have to replace it.

If I were upgrading the bikes, the roller brakes would be very low priority. If they were the primary braking system for a rig I was building, I'd probably be looking seriously at installing disks.

Jax Rhapsody

Those things you most commonly find on minibikes and cheap 2hp gokarts? I'd stay clear.