Author Topic: Best mechanical disk brakes  (Read 6350 times)

LittleWheelsandBig

  • Whimsy Rider
Re: Best mechanical disk brakes
« Reply #25 on: 17 April, 2021, 09:52:41 am »
I understand the GT-P uses a commonly available pad shape while the F1 and R1 use a rarer obsolete shape (don’t know about X1). We are hoping to keep using the brake for several years, so replacement pads that are easily available is a big advantage.
Wheel meet again, don't know where, don't know when...

Re: Best mechanical disk brakes
« Reply #26 on: 17 April, 2021, 03:10:12 pm »
Note, there are many reasons for choosing cable over hydraulics. Failure mode is one of them. If your brakes start giving you issues, 3 days away from the nearest big town on a big tour or race, chances are you can bodge a cable brake until you get to a proper bike shop. With hydraulics how do you fix them in the middle of nowhere?
Hydraulics may offer better braking performance, but at what cost.
J
The reality is that hydraulic is pretty much fit and forget. I've only ever bled such hydraulic twice since early 90s and even then it I think it was to learn how to do it. And guess what, it's not actually that hard. Probably easier than replacing a gear cable that's shredded inside your brifter. Now that's a real pig to sort out
I did snap a front hydraulic hose in an MTB race after straightening fork by turning it the wrong way and then forcing it. Duh! But that was an unusual fork that looked same even the wrong way around and was rim brake /hydraulics with short cable, so a bit of a freak incident caused by an adrenaline fueled idiot. Made for an interesting second half of race as we carried on. We is not a misprint there as I was piloting a drop handle barred tanden and that was interesting ride continuing the race with just a rear brake, went down the hills a lot faster on second lap.  ;D
In the 25 years since, only hydraulics issue has been sticky pistons on some very old brakes. Older than most folks bike. Had loads of issues with cables in that time and before.
The true cost to consider is inferior braking. And it's not hyperbole to say that can literally be a matter of life and death. 
The Tile Collector

Re: Best mechanical disk brakes
« Reply #27 on: 17 April, 2021, 04:18:28 pm »
As I started this thread ...

I have had two machines with hydraulic disks.  One was an mtb and the shimano xt disks were pretty bombproof.  However, it only got used on day excursions and was never going to be an issue if the brakes failed save for needing to scrub speed or stop in precarious circumstances.  The second was a bent which came as a secondhand purchase with Hope hydraulic disks.  The banjo? by a brake lever failed without warning pissing fluid all over my lap (tiller type steerer) and leaving me without a rear brake.

My plan for disks this time was for a touring machine.  I was once stranded for a week in Lerwick, Shetland because the local bike shops could not supply the part that I needed and I had to order it mail order and get it delivered.  On tour even in more remote areas of the UK parts can be unobtainable so simplicity for a tourer is desirable in my opinion.

It's all academic now as is can no longer ride but please, debate on.  🙂

LittleWheelsandBig

  • Whimsy Rider
Re: Best mechanical disk brakes
« Reply #28 on: 17 April, 2021, 07:15:30 pm »
If the relative strength of braking between cable and hydraulic disc brakes can be a significant safety issue, an overweight me must have real problems descending the Alps on single pivot sidepulls. It doesn’t seem to be a problem in reality.

On the last day of the most recent PBP Audax, a rider went off the road and pulled the hydraulic hose out of the olive when his Dura-Ace STI lever rotated inwards on the bar during the slow speed crash. That sort of movement doesn’t tend to do anything particularly bad to a brake cable.

Talking about full hydraulic brake systems is pretty much irrelevant to the question I asked. I would appreciate it if you took that particular discussion to a different thread.
Wheel meet again, don't know where, don't know when...

zigzag

  • unfuckwithable
Re: Best mechanical disk brakes
« Reply #29 on: 18 April, 2021, 12:55:14 pm »
one of my bikes has shimano cx-77 brakes, the performance is similar to bb7's, i wouldn't be able to tell the difference. one moving brake pad, so they need tuning (1min job) every few hundred km. they've been through some epic rides both on and off-road and worked just fine (and match the bike's colour..).

Re: Best mechanical disk brakes
« Reply #30 on: 18 April, 2021, 01:14:56 pm »
I've got BB5's on my Audax bike at the moment because that's what it came with. I planned to swap them out if they were no good but so far they've been good enough (will upgrade when they die). Seen me through everything for 3 years including the last PBP. Performance seems more about picking the right pads.

I've got XTR hydraulics on the mountain bike and yes, they will stop dead and lock up with a light pull but on a road bike prefer the piece of mind of mechanical.   
“Life is like riding a bicycle. To keep your balance, you must keep moving.” ― Albert Einstein

Adam

  • It'll soon be summer
    • Charity ride Durness to Dover 18-25th June 2011
Re: Best mechanical disk brakes
« Reply #31 on: 18 April, 2021, 04:47:07 pm »
Note, there are many reasons for choosing cable over hydraulics. Failure mode is one of them. If your brakes start giving you issues, 3 days away from the nearest big town on a big tour or race, chances are you can bodge a cable brake until you get to a proper bike shop. With hydraulics how do you fix them in the middle of nowhere?
Hydraulics may offer better braking performance, but at what cost.
J
The reality is that hydraulic is pretty much fit and forget. I've only ever bled such hydraulic twice since early 90s and even then it I think it was to learn how to do it. And guess what, it's not actually that hard. Probably easier than replacing a gear cable that's shredded inside your brifter. Now that's a real pig to sort out
I did snap a front hydraulic hose in an MTB race after straightening fork by turning it the wrong way and then forcing it. Duh! But that was an unusual fork that looked same even the wrong way around and was rim brake /hydraulics with short cable, so a bit of a freak incident caused by an adrenaline fueled idiot. Made for an interesting second half of race as we carried on. We is not a misprint there as I was piloting a drop handle barred tanden and that was interesting ride continuing the race with just a rear brake, went down the hills a lot faster on second lap.  ;D
In the 25 years since, only hydraulics issue has been sticky pistons on some very old brakes. Older than most folks bike. Had loads of issues with cables in that time and before.
The true cost to consider is inferior braking. And it's not hyperbole to say that can literally be a matter of life and death.

If it's not Shimano/Magura/Clarks, then anything else will be DoT fluid which does need bleeding after a few years (manufacturers recommend annually) due to the water absorption issue.  And if the brakes are modern SRAM (rather than Avid), then the actual process is a real pain.

“Life is like riding a bicycle. To keep your balance you must keep moving.” -Albert Einstein

Re: Best mechanical disk brakes
« Reply #32 on: 18 April, 2021, 08:58:29 pm »
A first mention for Clarks there. I've found them pretty good really. Focus on what's going to actually do the braking, which is the pad and the disc. I think I cooked a set of pads with a combination of Batheaston Hill down and not being careful enough with my lubricants later. Didn't matter what connected my intentions to the rubber - steel string or fluid straw at that stage.

Familiarity and confidence seem to be the overriding comments so far, which is for the logician anathema, but the human is just like that.
Cruzbike V2k, S40

Re: Best mechanical disk brakes
« Reply #33 on: 25 April, 2021, 01:52:00 pm »
Not mechanical, but disc brakes all the same:

Turned up for club ride yesterday morning. Next to our (Social) group was one of the faster groups
with a youngish guy (first to arrive for that group), whippet-thin racing type of rider. He had a nice
bike with disc brakes.

Me: Was there a steep learning curve in setting up your disc brakes?
Youngish guy: No, not really.
Guy next to me (to youngish guy): Have you bled the hydraulics yet?
Youngish guy: No, I get a bike shop to take care of all that stuff.


I thought it was quite funny.





Re: Best mechanical disk brakes
« Reply #34 on: 25 April, 2021, 03:34:53 pm »
Remarkably common these days among club riders with expensive bikes. Not just for disc brake maintenance either. I imagine that a lot of them can easily afford to pay for such services and they may well work long hours and prefer to spend their free riding their bikes rather than fettling them but I certainly could have that sort of relationship with my bikes, or other gear that I own, even if I could afford it. At least it keeps local bike shops in business which is a good thing.

quixoticgeek

  • Mostly Harmless
Re: Best mechanical disk brakes
« Reply #35 on: 25 April, 2021, 04:31:08 pm »
Remarkably common these days among club riders with expensive bikes. Not just for disc brake maintenance either. I imagine that a lot of them can easily afford to pay for such services and they may well work long hours and prefer to spend their free riding their bikes rather than fettling them but I certainly could have that sort of relationship with my bikes, or other gear that I own, even if I could afford it. At least it keeps local bike shops in business which is a good thing.

When you drop 5k on a bike, paying €50 to the bike shop once ever few weeks to keep it in order is not going to be noticed. Some will see it as part of their regular ritual. Drop by the LBS, hand the bike to the mechanic, grab a coffee, and catch up with people while it's worked on.

One friendly local bike shop here used to call me when ever they had a di2 customer, as they realised I know more about it than them, but I don't have the time for it any more.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Best mechanical disk brakes
« Reply #36 on: 25 April, 2021, 05:17:56 pm »
I do all my own bike work, bar warranty stuff and facing BBs, because it isn't worth me buying the tool. I prefer to do my own because I'm interested in how the stuff works, but also because it saves time, hassle and money.

I don't feel snobbish about this, and if people want to never touch their bikes that is fine by me. Most people don't service their cars, and yet it is no more complex than servicing a bike.

Re: Best mechanical disk brakes
« Reply #37 on: 25 April, 2021, 05:26:04 pm »
Still on rim brakes and tube tyres. The only stuff I can't do is insert/remove headset and build wheels.

Re: Best mechanical disk brakes
« Reply #38 on: 25 April, 2021, 05:28:12 pm »
I can  :P

Re: Best mechanical disk brakes
« Reply #39 on: 25 April, 2021, 05:43:22 pm »
I can  :P
I'll let you know when it needs doing. :thumbsup:

Cudzoziemiec

  • Ride adventurously and stop for a brew.
Re: Best mechanical disk brakes
« Reply #40 on: 25 April, 2021, 05:50:15 pm »
I do all my own bike work, bar warranty stuff and facing BBs, because it isn't worth me buying the tool. I prefer to do my own because I'm interested in how the stuff works, but also because it saves time, hassle and money.

I don't feel snobbish about this, and if people want to never touch their bikes that is fine by me. Most people don't service their cars, and yet it is no more complex than servicing a bike.
Interesting point. I do most stuff on my bikes but I never serviced my car (when I had one) beyond checking tyre pressure and oil every now and again. And yet when I had motorbikes, I did pretty much everything on those myself. I even tried setting the valve gaps, though it didn't really run very well until I'd done it again and then again.  :-\

The most difficult job (and relevant to this thread) I remember as being bleeding the brakes. Incidentally, my first ever motorbike had a mechanical front disk brake and it worked perfectly well enough to stop 170kg or so of motorbike and rider from 60-odd mph (it was only a small bike so didn't really go any faster than that). They certainly worked a lot more reliably than the drum brakes on the motorbike I had after that.

Anyway, I think the differential factor is that on a bike, whether pedal or motor, everything is fairly open and on display, easy to get at. No bonnet needs lifting, nothing is hidden under bodywork and you never need to crawl underneath and have oil and assorted chemicals drip on your face.
Riding a concrete path through the nebulous and chaotic future.

ppg

Re: Best mechanical disk brakes
« Reply #41 on: 25 April, 2021, 06:36:03 pm »
I think for elegant simplicity, the Campag dual-pivot side-pulls on my Audax bike take a lot of beating.

The Shimano mini-Vs on the tourer are also very good, and much better than the cantilevers on the Pompino.

I have no experience of hydraulics; my MTB has BB7s and I've never felt the need for improvement - though setting them up took a while to get the knack.

In short I don't really mind what type I use, they all bring my lardy-arse to a safe stop down the mountains of Exmoor here without drama.
IMHO, the choice of pads is probably more significant YMMV

Re: Best mechanical disk brakes
« Reply #42 on: 26 April, 2021, 07:24:10 pm »
I've just acquired a second-hand set of NUTT cable operated dual-piston calipers.
Now all I need is N+1 to try them out on....
 ;D

Re: Best mechanical disk brakes
« Reply #43 on: 26 April, 2021, 08:02:28 pm »
I do all my own bike work, bar warranty stuff and facing BBs, because it isn't worth me buying the tool. I prefer to do my own because I'm interested in how the stuff works, but also because it saves time, hassle and money.

I don't feel snobbish about this, and if people want to never touch their bikes that is fine by me. Most people don't service their cars, and yet it is no more complex than servicing a bike.
Interesting point. I do most stuff on my bikes but I never serviced my car (when I had one) beyond checking tyre pressure and oil every now and again. And yet when I had motorbikes, I did pretty much everything on those myself. I even tried setting the valve gaps, though it didn't really run very well until I'd done it again and then again.  :-\

The most difficult job (and relevant to this thread) I remember as being bleeding the brakes. Incidentally, my first ever motorbike had a mechanical front disk brake and it worked perfectly well enough to stop 170kg or so of motorbike and rider from 60-odd mph (it was only a small bike so didn't really go any faster than that). They certainly worked a lot more reliably than the drum brakes on the motorbike I had after that.

Anyway, I think the differential factor is that on a bike, whether pedal or motor, everything is fairly open and on display, easy to get at. No bonnet needs lifting, nothing is hidden under bodywork and you never need to crawl underneath and have oil and assorted chemicals drip on your face.

Accessibility and space is what makes the difference, bike, motorbike or car. I have always serviced (and rebuilt) my motorbikes but they were in general air-cooled and unfaired and I have never had affair with injection. The one that is in bits and for which I can't find the enthusiasm to finish the job is a GL1100 Wing; it needs space, is all at ground level and has water in it and bodywork around the outside. Cars, the same arguement; the 205 I could do everything on, even the entire rear suspension. Engine access good, no skidpan to mess up oil changes etc. I won't be doing the same with the Mégane that has replaced it - electronics everywhere, access nul. I think that this sort of reasoning will become more and more common with bikes, CBA to mess with electronic gears, don't have clean enough conditions to be happy working on the hydraulics, maintaining hidden hoses, wiring and cables is a pain etc, give it to the LBS. It may be perfectly simple when exposed but the fact of being hidden in the entrails puts people off. So far I am avoiding this situation by staying in the dark ages (while it's still relatively cheap) but the moment will come when....

To answer the question of LWaB the bike I had with disc brakes had a BB5 clone at one end and a Tektro IO at the other. Both were simple to maintain (I never took either apart; I tried it with another BB5 clone and dedded it in the attempt). They weren't any more powerful than the Vs that were on the bike before however and I never tested them in the wet but the Vs would lock the rear wheel rather too easily on wet roads. If I were building another bike with discs it would probably be BB7 on reputation or BB5 on experience. I am waiting to see how my daughter gets on with my old disc bike, she is starting from a lower knowledge point than me.