cable operated hydraulic brakes

Joined
Nov 27, 2015
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783
Location
S.E. Idaho USA
www.backcountry.com/trp-hy-rd-cable-actuated-hydraulic-disc-brake?CMP_SKU=TRP000A&MER=0406&skid=TRP000A-SI-S140MM&mr:trackingCode=47D1A5CC-60B5-E311-9C6B-BC305BF82376&mr:referralID=NA&mr:device=c&mr:adType=plaonline&CMP_ID=PLA_GOc001&utm_source=Google&utm_medium=PLA&k_clickid=f0b0021e-38a9-4a19-82c1-b3693762b6bb&rmatt=tsid:1042790|cid:213415837|agid:13362825397|tid:aud-112578408019:pla-441544380207|crid:92885919277|nw:g|rnd:3443195890455323137|dvc:c|adp:1o2|mt:|loc:9029429&gclid=Cj0KCQiAwp_UBRD7ARIsAMie3XZVVdQ0EZOBXTZbKo3nw0eiphXy9TTCh1afbGb778pq5mVWxxtjEtIaAp0HEALw_wcB
I am on the lookout to upgrade my folding Montague, which came with mechanical disc brakes, to something "better." It just came to my attention that there is something called a mechanically actuated hydraulic brake system. this really got my attention, as the main reason I don't have full on juice brakes, is because of the folding thing. It wasn't even an available option for me when I bought my Montague, and the Montague is the ONLY bike that is able to fit my exacting space limitations in my kit plane.

It fits so well, like the bike and plane were designed for each other, that I am not going to rock the boat and even consider another folder, I've been using the Montague/airplane combo now for around 20 years (3 different models) with fantastic results, and, while still unbelievable to me, the addition of a BBSHD conversion and a Rohloff hub, is proving to be also very practical. So practical, that I have many times found myself up a mountain, and wishing I had better brakes for the ride down. My Sturgis Bullet fatbike, with its juice brakes (and not top of the line high end ones either) is SO nice when braking, if I could get even half it's braking performance on the Montague, it's make it even better. My one concern about messing with my brake system, is that every time I fold the bike, I take the front wheel off, and it there is a big hassle involved putting it back on, as in getting the disc between the pucks, it'd be a deal breaker. Even right now with my stock brakes, fitting the front wheel back on properly is the most time consuming part of the minute or two at most unfolding process, I don't want vastly improved braking power if the cost is getting pissed off every time I have to put the front wheel back on!

Right now, I am ready to order a single setup for my rear wheel, where I'm sure it won't be any additional issue as I never take it off anyway, short of fixing a flat. That way I can first try it out on the front wheel. The whole thing seems almost too good to be true, juice brake power while still keeping my cables, which I know don't impede the folding process, that I am being on the alert for something that would be a major problem, like having an issue getting the front wheel back on. Worst case scenario, if that is an unavoidable hassle, I will go with just a rear wheel upgrade, and simply upgrade the front wheel to the TRP dual mechanical puck system they also have, though that also gives me some concern as to quick refitting.rsz_9-29-17_011.jpg
 
I've messed with those a little, and honestly they seemed a little over priced and underwhelming. The stopping power wasn't markedly better than well set up mechanical discs. You still have to contend with the pads closing up while the front wheel is out from accidental pulling on the brake cable. That requires sticking a screwdriver or something between the pads to spread them before the wheel will go back in, unless you put in the plastic wedge in the caliper every time.

I'm starting to think the main market for these units is road bikes with integrated shifting and brake levers for doing gravel bike conversions, when you need to keep your integrated levers, and there's no easy way to add hydraulic at the bar end of things.

I wouldn't expect night and day difference in braking is sort of the point. I also have a Montague folder, and could see the rear needing careful routing, but would just go full juice on the front... You can get a whole lever/caliper combo with bigger pads for less than just the cable actuated caliper.

EDIT... bigger rotors can add a lot to your existing units too if that's an option.
 
Years ago I spend some time "hotrodding" my Dahon folder. The brakes were a major concern because the main mod was to increase the gearing so I could maintain 20+ mph while commuting. As I recall, the bike had a drum brake on the back and a crappy, no-name, consumer sidepull on the front. Combined with the chrome plated 16" rims, the bike did not stop well.

The one thing that I did that might apply in your situation is that I installed heavy duty - I think 2mm - thick cables and the matching extra thick housing to go with it. This reduced cable stretch and sheath compression a lot and the brakes became a lot more responsive and solid. The other big difference was that I changed to a high quality brake pad. I forget the name, (Aztecs I think - Kool Stops probably didn't yet exist.), but they really improved the grip on the chrome rims. Those kinds of changes applied to your bike probably wouldn't deviate far from the original design and functionality.

I guess it really comes down to identifying where the weakness is. If the brakes feel mushy, then my suggestions might help. If it is something else, then maybe not.

TS560x560
 
BTW, I thought one of the main advantages of hydraulic brakes was that they reduced slop in the system. Running a cable to a hydraulic caliper would take away that advantage and reduce effectiveness.

If cable flex is a significant part of your problem, then maybe some of the new hi-teck synthetic cables and non-flexing sheaths (Nokon) could be worth looking at.

This whole area seems like something about which Chalo could give you some good insight.
 
wturber said:
BTW, I thought one of the main advantages of hydraulic brakes was that they reduced slop in the system. Running a cable to a hydraulic caliper would take away that advantage and reduce effectiveness.

It restores a choice of lever shape and mechanical advantage that you don't get with end-to-end hydraulic systems.
 
I have a set of BB7 cable discs on my fastest bike. I dunno if there's really much difference. I found that KoolStop eBike (grey pads) and KoolStop MTB pads First ordered in Aug 2014 on the recommendation of Chalo,Kool Stop MTN Mountain Bicycle Brake Pads (Threaded, Salmon). Are nearly as good as the Koolstop Grey eBike, and the BB7 are maybe a bit shorter stopping distance, but not consistently IME. I know it raises the ire of many but 26" rims make for 26" discs. I'm not a speed crazed rider so take my experience with a grain of salt.
 
wturber said:
BTW, I thought one of the main advantages of hydraulic brakes was that they reduced slop in the system. Running a cable to a hydraulic caliper would take away that advantage and reduce effectiveness.

If cable flex is a significant part of your problem, then maybe some of the new hi-teck synthetic cables and non-flexing sheaths (Nokon) could be worth looking at.

This whole area seems like something about which Chalo could give you some good insight.

Prob the biggest advantage on hydraulic brakes is they self adjust as the pads get thinner from wear, so the lever feel is always the same until it's time for new pads. Mechanical disc can stop just as well, but takes periodic readjustment to keep from feeling mushier and mushier as the pads thin out.
 
Voltron said:
Prob the biggest advantage on hydraulic brakes is they self adjust as the pads get thinner from wear, so the lever feel is always the same until it's time for new pads. Mechanical disc can stop just as well, but takes periodic readjustment to keep from feeling mushier and mushier as the pads thin out.

I come across lots of hydraulic brakes whose levers squeeze right to the bars despite the pads having plenty of thickness. Remember that the intended characteristics of such brakes require an uninterrupted column of hydraulic fluid between master cylinder and slave cylinder. In practice there are often significant quantities of air and/or water in the way. And that's assuming the system isn't leaking badly enough to push fluid out when applied.

I've never come across a cable so bad that it leaked out. Just sayin'. Though I have encountered cables that had air gaps! Those don't work too well.
 
Many of the times I've had customer bikes come in with the levers to the bar, all the was needed was setting the reach adjust and the brakes were back to perfect. Other times the mushy feel was from someone using the wrong size bleed block, resulting in the system being underfilled. Maybe it's the dry climate, but never seen actual water intrusion, esp with the mineral oil ones where the fluid doesn't absorb moisture like DOT fluid does.
 
In my observation in the shop, at least nine in ten of the cable brakes that have serious problems could be fixed in the field with simple tools by someone who understood them. But maybe one in ten of the hydraulic brakes with failures could have been fixed without workshop resources. A larger portion aren't even worth fixing at the shop labor rate, and get replaced instead because it's cheaper.

The only situations where I'd consider using a hydraulic brake over a cable brake are if the routing between the lever and caliper is long and indirect, or if the lever must work more than one caliper. Otherwise, the likelihood of immediate 100% loss of braking makes hydraulics not worth it. Brakes are too important for that.
 
I'm sure it happens sometimes, but I've never seen a properly set up hydraulic just completely fail. Even the ones that developed leaks didn't suddenly stop working but got gradually mushier as the fluid levels dropped, until the customer finally brings it in when its dead empty.. But I have had cable brakes snap the cable at the pinch bolt or at the lever from flexing and fraying.. That isn't very fixable in the field either, unless one is carrying a spare brake cable.

One could make the argument that having brake pads slowly scrubbing thru the sidewall of the rim until it fails unexpectedly is not an acceptable failure mode either.

From a recent customers rerimming job off his ebike.
rimcrack.jpg
rimcrack2.jpg

But of course, everybody has feelings about different features and disadvantages of things that are more or less important to them when choosing.
 
I don't like rim brakes, but that failure doesn't look like it was caused by brake wear. The outside sidewall is all black rather than bare alloy, so the anodizing is intact, something a worn rim wouldn't have. Looks more like it was a simple weakness caused by a manufacturing problem.
 
It's a trick of the light.. the rim has machined sidewalls, the kind with two grooves cut into it, and you can see the silver grey color near the bottom on the first pic.. It was def pad wear combined with high PSI tires.

But I would agree the manufacturing didn't help by having one of the outside grooves adjacent to the step in the double wall on the inside... that wasn't good as the sidewall thinned out over time.
 
Wow, thanks for the input you guys. I'll ponder it all before doing anything, but pretty much have decided not to go with them on the front anyway. I like the Nokon cable and housing suggestion, especially as it's supposed to not be any more weight, that sounds like a good idea no matter what brake I go with. I really would not have any brake issues, if the bike didn't perform so well and get me up places I have to ride down! They are more then satisfactory for town riding.
 
Voltron said:
But I have had cable brakes snap the cable at the pinch bolt or at the lever from flexing and fraying.. That isn't very fixable in the field either, unless one is carrying a spare brake cable.
It is if you have a way to cut the housing down a bit ("leatherman" type tool has enough stuff on it to do this), and there's sufficient cable length to not pull on the brake when you are turning the bars. :) At the pinch bolt, just feed the cable back thru and retighten. At the lever, tie a knot or two in it, fat enough to stay in the lever slot. (I've had to do both before)


One could make the argument that having brake pads slowly scrubbing thru the sidewall of the rim until it fails unexpectedly is not an acceptable failure mode either.
If you have rims that have the "wear line" you can generally predict when to change the rim out, so that its not unexpected. :) But sometimes that wear line is made in such a way as to allow failure, or something else happens (like a big hit on a pothole or curb jump) that fractures it there.

In this case I suspect the latter helped cause this failure, along with the step on one side and cut on the other as you pointed out.

I haven't ever had a rim with a double wear line, but it seems like a bad idea--it reduces the surface area used for braking and it makes one more potential failure point.


But rim brakes aren't the only cable-operated brakes; some disc are, too. ;)


Though that is the one part of rim brakes I don't like: wearing them down--but with potholes and whatnot, I don't think I've actually worn thru a rim before destroying it in some other way. :lol: Like this (though no brakes on this wheel other than the motor):
https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&start=650#p1359023
file.php
 
Voltron said:
Prob the biggest advantage on hydraulic brakes is they self adjust as the pads get thinner from wear, so the lever feel is always the same until it's time for new pads. Mechanical disc can stop just as well, but takes periodic readjustment to keep from feeling mushier and mushier as the pads thin out.
Simple adjustment was one of the reasons I went with BB7's.

These can be incrementally field adjusted without tools just by turning the inner and outer knobs a click. This is really all you generally need on the trail to restore throw and feel, but an effective ground-up centering adjustment is also quick to do wherever you are. Repeatedly squeeze the brake while rotating in the inner knob a click at a time until the disk stops deflecting then run the outer knob down snugly. Back both knobs off three clicks. Done in two minutes w/o tools.

The inner knob can be stiff on new BB7s making a torx driver sometimes necessary. Before I install them I pull off the inner plastic adjuster wheel and lightly dress down the detent-grabber points using a drum sander on a Dremel. Still grips like crazy but finger adjustment becomes easy - even with the hub motor.

I've got BB7s on both bikes, one a Paratrooper. Like 'em a lot...
 
Yes... the BB 7s are hard to beat for ease of adjustment, along with having bigger pads than the BB 5s. Theres a few designs coming out that move both pads at the same time, unlike the BB series where only the outside one moves, but they are all crazy expensive and hard to find pads for. You also lose the ability to recenter the pads over the rotor for a wheel that got taken out and put back slightly offset, so not sure they're going to be a product that is worth it. Many mechanicals are terrible when combined with a hub motor too.. there's no way to adjust the inside pad without either making a special shorty allen wrench to fit past the motor, or taking the brake off, guessing on how much to move the inner pad, then remounting it to see if you guessed right. Compared to their normally stellar hydro brakes, the Shimano mechanical is terrible, esp on the issue of reaching the inner pad past a motor. The dial on the BB 7s is so easy comparatively.

For now the BB 7 is hard to beat, but it is truly astounding to me how many customers come in with mushy brakes and don't know the inside pad adjusts, so its worn so far the rotor is grinding into the caliper body as the rotor deflects. That's not the astounding part tho.. its that even after you explain it to them, and show them how easy it adjusts, and what to listen for to set the clearance... they just completely do not get it, and will keep coming in every three months to pay $50 to get it done for them.

Side trivia for brakes... the BB stands for ball bearing... thats why the Avids perform much better than most of the other mechanicals. They have ball bearings in the action that help it push the pad nice and square and not develop slop over time. Most of the others get wiggly over time and start pushing the pad crooked so it wears quicker and makes adjusting them really hard. The Shimano mechicals are again terrible for this.. so annoyingly floppy on the action after short use.
 
For AW... "If you have rims that have the "wear line" you can generally predict when to change the rim out, so that its not unexpected. :) But sometimes that wear line is made in such a way as to allow failure, or something else happens (like a big hit on a pothole or curb jump) that fractures it there."

I'm not sure that really is a wear line.. I had heard it was more of a ventilation channel, much like vented disc rotors. Regardless, this is maybe the sixth rim I personally have seen do this kind of thing, and none of them had reached the bottom of the groove, so not sure how good a wear indicator it would be, esp given human nature re. warning signs. If maybe it had bumps or something that would start juddering the brakes as a warning. But many customers I get seem to barely notice tires worn to the casing, skipping gears, rubbing brakes, or much of anything really... not sure how much a visual wear line is going to make them wonder if their wheel is about to break.
 
Yes..the Spyres are nice units. The pads can be individually adjusted so as long as you have the allen wrench you should be able to recenter if its rubbing. And they leave you time for plenty of extra drinking according to their ad copy in that link. :wink:

No matter what ones you pick, ordering spare pads ahead of time is something to think about.
 
craneplaneguy said:
Teklatik: You have a Paratrooper, do you deploy it several times a day, or rarely? In other words, how is it (putting the front wheel off and on) with that BB setup?
Every day when weather is good. The brakes are no issue when reinstalling the front wheel. I have a 160 up front so it's harder to twang when off the bike and minor skewer seating errors result in less side to side displacement at the caliper than with a big rotor. Easy-peasy - no problems at all.

craneplaneguy said:
I could see using a puck (or whatever they are called, the spacer to keep the calipers apart) every time I pull the wheel, that could be quick and easy enough to mess with and not a deal breaker if the brakes performance made it worthwhile.
The normal BB7 spring retainers for the pads hold them seated back in the calipers just fine. The pads are gapped just like normal so the disk slips right in.

Across the board the thing I like about the BB7s is that the darn things just work. They are 'invisible' and I never have to think about them.
 
I have a couple bikes with rim brakes and have been thinking about trying one of the Magura Hydraulic Rim Brakes that are like the downhillers used to use. Anyone have any experience with them?
 
Raisedeyebrows said:
I have a couple bikes with rim brakes and have been thinking about trying one of the Magura Hydraulic Rim Brakes that are like the downhillers used to use. Anyone have any experience with them?

I had a pair in the early '90s. They were very strong and precise. I stopped using them mostly because I didn't like the lever. Since then, the levers have gotten much better and pad selection has increased.

Good pads and good setup on linear-pull brakes can give you equal performance in most circumstances. But if your cable routing is tortuous or the housing run is long, hydraulic rim brakes can address those things.
 
Raisedeyebrows said:
I have a couple bikes with rim brakes and have been thinking about trying one of the Magura Hydraulic Rim Brakes that are like the downhillers used to use. Anyone have any experience with them?

these were also really popular on bicycle trials bikes because you could really lock up the brakes and hold the bike on near vertical terrain / obstacles using minimal hand pressure at the brake lever..
 
Chalo said:
Raisedeyebrows said:
I have a couple bikes with rim brakes and have been thinking about trying one of the Magura Hydraulic Rim Brakes that are like the downhillers used to use. Anyone have any experience with them?

I had a pair in the early '90s. They were very strong and precise. I stopped using them mostly because I didn't like the lever. Since then, the levers have gotten much better and pad selection has increased.

Good pads and good setup on linear-pull brakes can give you equal performance in most circumstances. But if your cable routing is tortuous or the housing run is long, hydraulic rim brakes can address those things.

I'll have to see if one would fit on the back brake position of this project I'm working on, it does not have disk tabs on the back, the forks do, but I thought the hydro rim brakes might be something interesting to try, the Magura's look like a nice beefy brake.
 
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