DIsc brakes for a tourer; shall I just give in?

[quixoticgeek]

Also, this view may not be flavour of the month (and maybe the OP has already made his mind up/followed the herd, so I am wasting my time even mentioning it) but there are plenty of good reasons not to want disc brakes on a touring bike.

Ooh, do tell, I'm about to buy a disk brake frame. Tell me why I shouldn't?

I personally dislike anything I can't service by the road side with the tools I have on me. This procludes internal gear hubs, and internal braked hubs. For pretty much everything else I can service it with the tools I carry, at least to the point that it'll get me to the next bike shop, or location I can get parts posted to. Sure I may have to do the next 100k on what is essentially a fixed gear, or single speed.

This is where you have to consider the failure mode of hub gears and hub brakes. They are very reliable, right up to the point they aren't. And it's that point when things get complicated.

J

[Samuel D]

It’s not hard to build a bicycle around the components you want. It doesn’t even cost more for most people on a forum like this (with tools and probably a few parts already in the shed, not to mention a deep knowledge of standards and parts compatibility whether you realise that or not).

Since I have strong and sometimes – bafflingly! – unconventional opinions on even the minor components, there isn’t a hope of my finding a suitable ready-to-ride bicycle. The gearing will be wildly wrong, the saddle won’t suit me, the budget will have been spent in flashy places rather than the right places, the tyres will be unfit for purpose, and these days, yes, the brakes will be wrong. And that’s before considering the aesthetics of it all.

So I wouldn’t dream of buying a built-up bicycle. I suggest you don’t do that either, unless you want to spend the next three years replacing every part at double the initial expense.

And if for some strange reason you want simple, functional, economic, elegant rim brakes, by however slight a preference, well, now’s the time to get them. Who knows what the choice will be like by the time you buy your next bicycle? The future is not looking rosy for rim brakes, which are, after all, useless in the rain, unnervingly cheap to buy and maintain, and in a word unfashionable.

[Sergeant Pluck]

I suppose one consideration should be the anticipated use and the weather. To my mind, if there is a lot of off-road riding planned (unmade roads etc.) in wet regions, that favours non-rim brakes.

[LEE]

I have 2 bikes with disc brakes:

1) Genesis Single-speed with Avid BB7 cable actuated calipers.  Love them, very simple to set up and maintain.  totally serviceable by the roadside.

Reason for the choice: It's my winter Hack bike so I wanted something with wet-weather braking and that wouldn't grind my wheel rims into a filthy alloy paste.

2) Trek Domane with Shimano hydraulics.  No experience yet of faffing with pipes or bleeding.

Reason for the choice: I'm selling quite a few bikes and wanted something to replace a few of them.  The supplied Vision wheels retail for £1600 so disc brakes mean they will last and make expensive wheels a viable option for me.  Also they are in a different league of braking.  So much modulation but so much effortless power on tap if you want.

I know about all the disadvantages but I'm off to the Alpine climbs next summer and, as an engineer, I'm never truly happy when using bits of rubber, pressed onto an ever thinning slice of aluminium, to slow me down on precipitous descents.  I like the rotor to do the job of braking and the wheel rim to do the job of steering without wearing away.

Using wheel rims as braking surfaces is the odd concept really. 
If we'd started with disc brakes I doubt any engineers would have come up with rim braking as a winning idea.  They are initially over engineered and too heavy. 
They slowly grind away until they reach, for a few brief miles, an optimal point of weight and structural integrity before crossing the line into nice and light but not really strong enough any more.

Oh yes, add some sleet, make sure the braking surface is dipped into deep puddles every second, coat with grit and scrape the entire lot into the braking surface. 
It's one of life's miracles that they work so well really.

I'd have had them on my heavyweight tourer like a shot.  Every single Mountain bike of any note has had them for bloody years, it's well-proven tech.

Oh yes...lovely beefy thru-axles for some nice fully-loaded cornering.

[Cudzoziemiec]

That's a somewhat doom-prone view, Samuel. I think the majority of bikes you'll find on sale in any shop today have rim brakes, although probably most MTBs have discs.

As for building bikes up to personal preferences, yes, most definitely; and ready-built bikes are often a very good way to do this in a gradual way, finding out what you like or don't like as you go along and all the time having a rideable bike. For instance, I've had my favourite bike for four or five years now, during which time I've changed: bars, stem, seatpost, saddle, wheels, cassette, rear derailleur and most recently crankset. Oh, and bottom bracket. Still on the original pedals though! That list obviously doesn't include consumables like tyres and chain. It might well have been cheaper for me to buy the frame and build it up with the present parts myself; but I would have been choosing parts in the dark (and inevitably made different choices from what I have now, some maybe better but probably some worse) as opposed to how I have done it, changing parts on an experience basis. Doing it over time also spreads the cost out! And the parts you replace you can either keep for spare, sell for cash or donate to a worthy cause.

[mrcharly-YHT]

Also, this view may not be flavour of the month (and maybe the OP has already made his mind up/followed the herd, so I am wasting my time even mentioning it) but there are plenty of good reasons not to want disc brakes on a touring bike.

Ooh, do tell, I'm about to buy a disk brake frame. Tell me why I shouldn't?

The only serious reason I've heard of is disc warp.
Some blog written by someone doing serious mountain touring, off in the 'stans, managed to warp his disc from heat when descending mountains. Then he was stuck because he couldn't straighten it well enough and was hundreds of miles from a bike shop. He reckoned canti's were easier to bodge-repair.

I'm unconvinced, mostly because I've worn out a set of canti blocks in a month - and I wasn't touring with a heavy load in dirty conditions.

[Kim]

I have 2 bikes with disc brakes:

Similarly:

1) B-Twin hardtail with entry-level Tektro hydraulics.  Consistent performance in mud, which is what it's all about - a massive improvement over the V-brakes on my hybrid, and no rim wear.  Not done enough mileage to perform any maintenance yet, but at the first sign of trouble they'll probably be replaced with something designed to be serviced, but still hydraulic.

2) SMGT heavy tourer with BB7s and an Avid V-brake on the rear as a parking brake.  Ease of adjustment, eliminates rim wear issues which would be a bigger deal on a 406 front wheel.  Consistent performance for fast descents with a heavy load.  I carry a lockring tool in case the front rotor^[1] (or rear cassette) needs to be removed for spoke replacement, but that's not happened yet.  Parking brake for convenience and to scavenge for parts if something important fails (the shifters are particularly vulnerable to crash damage, so having a spare along is a good idea).

I bent the rear rotor once while re-fitting the wheel after a puncture repair, resulting in annoying scraping noises.  Some quality time with a small adjustable spanner put it right.  Less complicated than truing a rim.

3) Optima Baron with some older-model Shimano XT cable discs.  Frame/fork have no mounting points for rim brakes, so discs it is.  Braking performance similar to BB7s, feel is much stiffer and deader.  Adjustment more fiddly than BB7.  IMHO this bike would be fine (and lighter) with a token road rim brake on the rear, as the geometry means nearly all the braking happens at the front.  Anything less powerful than a V-brake on the front would be scary, given the speeds it can achieve.

4) ICE Sprint trike with BB7s on the front and an old Tektro thing from the spare parts bin as a parking/emergency brake on the rear.  Being a trike, it had to be some sort of hub brake on the front wheels, and given fair weather low-mileage use I saw no pressing reason to opt for the more expensive drums option over BB7 discs.  The dual-pull control arrangement for the front brakes is fiddly to balance, and an expensive hydraulic solution would likely work much better, but that's a disability-specific mod.  When correctly adjusted the braking performance is spectacular, maintenance in line with the BB7s on the SMGT.  No regrets.

By way of comparison, my daily hack has Tektro V-brakes which work admirably well in the dry.  Adjustment is a fiddly bastard of a job, which is the main disadvantage.  I occasionally get caught out by the poor wet weather performance, but since I'm no longer using it for muddy off-road, not to the point where I have a pressing desire for discs.

I also have a Brompton, with its custom dual pivots.  They're best described as 'adequate', but the priority here is weight.  Discs on a Brompton seems daft.


_{[1] Centerlock because SON Delux.  I'd strongly recommend 6-bolt rotors (and a suitable multi-tool) for a tourer.}

[Sergeant Pluck]

The only serious reason I've heard of is disc warp.
Some blog written by someone doing serious mountain touring, off in the 'stans, managed to warp his disc from heat when descending mountains. Then he was stuck because he couldn't straighten it well enough and was hundreds of miles from a bike shop. He reckoned canti's were easier to bodge-repair.

A little adjustable spanner closed up against the disc and used as a lever is enough to bend the disc. Or a pair of pliers would do it, using something to prevent indentations on the disc. I would have thought that it would be possible to straighten a warped disc enough to allow onwards progress.

As an aside the stupidest thing I have done with discs was to spray water on them, by way of entertainment and to confirm that my discs did indeed get very hot. Only it wasn’t water, the bidon had some form of sugary energy stuff in it. Instant deeply embedded carbonised grot and a new disc. 

[frankly frankie]

I would vote discs and, more specifically, BB7s.

Agreed.  BB7 is a no-brainer for a tourer.  (I hear mixed things about the TRP Spyre, which is the other cable disc worth considering.)

I've used BB7s for many years and migrated to Spyres for this year.  The BB7s have bags more stopping power (similar composition pads in each).  I'll be swapping back when next I strip the bike down.

I'd strongly recommend 6-bolt rotors (and a suitable multi-tool) for a tourer.

Most multitools do have a T25 bit, but if not, simply replace the supplied bolts with allen-headed ones.

[HeltorChasca]

I have a Surly DT with Avid BB7s. In 3 years I've never had an issue. Much easier to service than rims in my opinion. In fact all my bikes have discs now. Just my daughters' (pl) with rim brakes. Don't let  it put you off.

Why the Surly CC over the DT out of interest?

[LEE]

I have a Surly DT with Avid BB7s. In 3 years I've never had an issue. Much easier to service than rims in my opinion. In fact all my bikes have discs now. Just my daughters' (pl) with rim brakes. Don't let  it put you off.

Why the Surly CC over the DT out of interest?

BB7s are the best cable operated disc brakes I've come across.  Very easy to back off the pads in case of disc warp and very easy to set the gaps with a true rotor.

I've serviced them a couple of times by taking them completely apart and am impressed with their simple design and small number of parts (a positive thing when you're talking about brakes).

[Brucey]

Also, this view may not be flavour of the month (and maybe the OP has already made his mind up/followed the herd, so I am wasting my time even mentioning it) but there are plenty of good reasons not to want disc brakes on a touring bike.

Ooh, do tell, I'm about to buy a disk brake frame. Tell me why I shouldn't?....

If you can find a brake manufacturer that owns up to making 'disk brakes' go ahead, but I think you will be buying a 'disc braked frame'... . As with most things it is a matter of judgement and priorities. 

BTW I agree with those that like BB7s,  in that I think they are good brakes, not perfect by any means but pick of the bunch when it comes to readily available cable-operated discs.  But picking those presupposes that you want disc brakes,  and maybe you don't.

Some issues that you may or may not find significant, off the top of my head, in no particular order;

1) Disc brake fittings make frames heavier.  (You don't believe me? -ask Zinn and others who have no particular axe to grind)
2) Disc forks are (if they are steel especially) both heavier and stiffer than non-disc forks.  Maybe you need a 1-1/8" steel steerer (eg for heavy loads) but for most purposes 1" is plenty. A steel 1-1/8" disc fork is typically between 1/2lb and 1lb heavier than a rim brake fork with a 1" steerer, and usually feels completely unyielding by comparison.
3) Disc wheels are heavier, and the spokes are more likely to break (they see more stress). 
4) If you prang a non-disc wheel or need brake blocks, you will be able to pick something up that will work virtually anywhere; not so for discs.
5) Discs often get bent in transit and when the bike is parked. I would advise anyone who is shipping their bike to remove the discs and secure them between the spokes.
6) If you need to replace a spoke you need to remove the brake disc in most cases.
7) Disc wheelsets have a (weaker) dished front wheel and a rear wheel in which the wheel dish cannot easily be varied. By contrast the rim-brake wheelset on my tourer has an undished front and an almost undished rear, that I (basically) couldn't have with disc brakes.  Undished wheels are unquestionably  stronger than dished wheels; how much? -well about the same strength if a dished wheel is built with a rim that is about 100g heavier, I reckon.
8 ) Discs and pads get contaminated.
9) discs also wear out
10) discs sometimes crack
11) discs are relatively easily overheated; one lass managed (without trying) to turn her discs blue in the south Downs; what they would be like in the alps goodness only knows. Overheating afflicts cautious riders and those heavily loaded (because they tend to drag the brakes all the way down) more than non-cautious/lightly loaded riders.
12) Hydraulic discs boil up and/or leak oil, and/or come on (or off) by themselves at inconvenient times.  I have not yet owned a vehicle with hydraulic brakes that is immune to such things.
13) Organic disc pads can wear faster than any known form of brake when used in wet conditions. I have seen a set of brake pads disappear in a single day's riding.
14) Disc pads are usually ~4mm total thickness, with 2.4mm of friction material. Most brake manufacturers recommend that you change the pads out when they are worn about 1.2mm. Inspecting for wear is difficult and fiddly with some calipers.
15) Sintered disc pads work more consistently than Organic ones and last longer, but may wear the disc faster, are not permissible with every disc, are noisy in operation, and may reject more heat into the brake caliper, exacerbating any overheating/boiling issues.
16) Many disc brake calipers are badly designed such that (when worn) the brake pads can simply drop out of the caliper
17) Some pad/disc combinations have zero initial bite when soaking wet. Think like chrome steel rims and rubber brake blocks; like that. For planned braking this isn't a big problem but I packed in using a disc braked bike for commuting, because I was worried someone would step off the pavement in front of me and I wouldn't be able to stop. (This was well before Charlie Allison BTW....) 
18) disc systems overheat on long descents; even BB7s can end up with Salvador Dali- style adjuster knobs when the calipers get properly hot.
19) disc pads vary in quality and durability. I have seen an unreasonable number of brake pads (from several manufacturers not just one) where the friction material has come away from the backing (= no brakes)
20) Discs get hot on long descents; look at the (few) disc brakes that are recommended for use as drag brakes on tandems by trustworthy tandem suppliers. They tend to have mechanical discs that are huge, (300-400mm dia)
21) discs get hot on long descents; when disc brakes were a relatively new idea a standard test was proposed, that equated to a descent of a real mountain road that is regularly ridden by cyclists. When no-one could make a disc brake that would pass this test, the disc brake manufacturers arbitrarily made the test half as difficult to pass. Duh...
22)  sandwich construction discs can get so hot the middle (aluminium) layer of the sandwich can melt
 23) some (fortunately rare) disc calipers are stupidly designed so that the arm stops moving at what appears to be half-travel, or even goes 'click' and stops working entirely. 
24) BB7/BB5 use swivelling (CPS) washers to help align the caliper. These often crack, at best letting the caliper flap about uselessly, at worst jamming the disc or leaving you with a brake that doesn't work. This is enough of a problem that a third party has made stainless washers of the right type available.
25) BB5 and BB7 calipers have a fixed pad adjuster that is threaded into the caliper body. In winter use this often seizes up so badly the brake is scrap.
26) I have never owned a disc braked bike on which I did not have multiple issues of the brake rubbing
27) If you have QR wheels then expect the brakes not to centre the same each time the wheel goes back in and/or the wheel to move when the brakes are used
28) If you are buying disc-braked wheels for touring on the choice of properly strong 36h hubs is rather small. Shimano appear to be giving up on them.
29) Under braking the loads on the hub bearings are between x4 and x8 more than normal ('normal' being on a rim braked bike). I have seen several hubs show premature wear in the LH bearing because of this.
30) discs present a nice sharp edge in even a minor prang.  You are not allowed to drive a car around with anything as sharp as a bicycle brake disc edge showing at the front.
31) disc brakes get very hot on long descents; folk regularly burn themselves quite badly on hot brake discs, or ruin their luggage, etc etc
32) if you swap disc-braked wheelsets the wheels invariably don't recentre without the brakes rubbing, even with notionally identical hubs and discs fitted.
33) Your chances of borrowing a disc braked wheel and having it fit and work correctly without a lot of faff are pretty small.

Now I'm not pretending that things are universally rosy for rim brakes or drum brakes either by any means, but I have learned to live with their shortcomings. By contrast I'm not sure I could ever learn to live with some of the shortcomings of disc brakes.

Re the reliability of IGHs and drum brakes. These can be incredibly reliable.  In my own experience a fault that either leaves you with one brake or (with the IGH) leaves you unable to ride is very uncommon. How uncommon? Well I'd expect to break a frameset several times (and have done) in the interval  between such failures.....

cheers

[zigzag]

hilly and wet audaxes/rides are where disc brakes truly excel. as i do those kind of rides a handful (if that) times a year my disc braked bike sits patiently in the shed most of the time.

[Cudzoziemiec]

As I said, I looked in SJS and found one.

you didn't look very hard....

Okay, a second look at SJS turned up quite a lot. Their product categorisation is a bit crap and you have to search using the search box. The majority, though, are with integrated hub gears.

you looked a bit harder....

That's actually a pretty good test for availability or more accurately ease of availability. If you know what you want, are enthusiastic and have enough background knowledge, you'll probably be able to find it (as long as it exists). So it is with drum brakes; you'll find them if you know they're what you want and are aware of places like SJS. Disc brakes and rim brakes you'll find in any bike shop, physical or webby, and you'll see them in the street so know they exist even if you don't know what they're called.

Of course this applies to everything, not just cycling and is affected by all sorts of cultural, financial and legal factors. It's easy to buy alcohol and knives but you have to know where to go for heroin and guns (at least in the UK). Geographical variation might conceivably be a problem for a long tour. I could get blocks for rod brakes from just about any LBS in India, not so in UK (though I used to buy them in the '80s). Both places it's easy to get pads for all types of rim brakes and disc brakes, neither will I find shoes for drum brakes but I'm guessing I would in maybe Germany.

[hubner]

...

Some issues that you may or may not find significant, off the top of my head, in no particular order;

1) Disc brake fittings make frames heavier.  (You don't believe me? -ask Zinn and others who have no particular axe to grind)
2) Disc forks are (if they are steel especially) both heavier and stiffer than .....

 [snip]

...
33) Your chances of borrowing a disc braked wheel and having it fit and work correctly without a lot of faff are pretty small.

Now I'm not pretending that things are universally rosy for rim brakes or drum brakes either by any means, but I have learned to live with their shortcomings. By contrast I'm not sure I could ever learn to live with some of the shortcomings of disc brakes.

Re the reliability of IGHs and drum brakes. These can be incredibly reliable.  In my own experience a fault that either leaves you with one brake or (with the IGH) leaves you unable to ride is very uncommon. How uncommon? Well I'd expect to break a frameset several times (and have done) in the interval  between such failures.....

cheers

That's the most amazing post I've read on this forum!

Don't let the supposed non-availability of parts put anyone off from using what they like. OK you might not be able to get stuff from the typical LBS, but it's all out there; freewheels, quill stems etc, some design classics are even being re-manufactured, and obviously there's secondhand.

I don't think there's any problem using rim brakes with regards to availability of parts. I'm using a brake that was first introduced in 1967, although mine were made in the early 80s but of exactly the same design. I recently fitted NOS blocks but as they're just blocks of rubber, you can adapt any blocks to fit. And one cable adjuster rubber ring has broken off but can be replaced by an ordinary o-ring of the right size.

[Brucey]

That's actually a pretty good test for availability or more accurately ease of availability....

its a test; not a very good one, if you search anywhere using the wrong terms.  It should be obvious that hub brakes are available, Pashley (and others) don't get them made by pixies... Call me a boring old traditionalist but almost any LBS will get you any current SA hub from the wholesalers I mentioned previously.

New drum brake linings are required about once every five or ten years. The specification they were asked to meet was to survive five year's worth of daily use by the GPO, and they do.

  The chances of needing a new set of shoes mid-tour are virtually nil; SA don't advertise the fact but when the brakes are new the arm on the brake plate moves only a short way from its rest position (with a slack cable) before the brake comes on.  The useful total travel in the arm (as the brake shoes wear) is about 45 degrees or something, before the arm on the front brake is in danger of clouting the axle in the hub.  When the arm gets close to that limit, (which coincides with the barrel adjuster in the cable running out of travel...) the brake shoes are worn out. Until then the brake will work normally; most users won't have to even look inside until the shoes are worn out.

cheers

[zigzag]

with the drum brakes - is there a trick to make them work better? the ones i've used before worked about the same as the old single pivot ones (weinmann, mafac etc), only consistently in dry and wet. i presume 90mm drum brakes are more efficient, but they are also much heavier/bulkier.

[mrcharly-YHT]

The SA alloy drum brakes weigh little more than a rear hub.
They work very very well.

The modern shimano roller brakes I'm not such a fan of, they work fine for light braking, but not for heavy braking. Require very little effort for light use. Superb brakes for town work.

[joy of essex]

Why is when anyone asks about Disc brakes that a thread like this happens! 

The point I was making was that one no longer has much of a choice. Try finding a  non-disc touring frameset.

[Brucey]

to make drums work well, use short pull levers and be patient; they can take about a year to bed in, in flat terrain.

cheers

[Jakob W]

Why is when anyone asks about Disc brakes that a thread like this happens! 

The point I was making was that one no longer has much of a choice. Try finding a  non-disc touring frameset.

Surly LHT, Spa Tourer, possibly Dawes Galaxy?

[Brucey]

Why is when anyone asks about Disc brakes that a thread like this happens! 

The point I was making was that one no longer has much of a choice. Try finding a  non-disc touring frameset.

Surly LHT, Spa Tourer, possibly Dawes Galaxy?

Condor, Hewitt, Woodrup, Fuji, Jackson, Mercian, Yates, Raleigh etc etc

try not to let your choices be confined to whatever evans and wiggle want to push down your throat this week....

cheers

[nobby]

<snip>
I would vote discs and, more specifically, BB7s.

+1 for BB7s. Got them on both road and mountain bikes took a short while to get used to setting them up but once mastered can be done in a few minutes. Certainly faster than rim brakes

Are the BB7's Avid's?
If so, what are there advantages over the Shimano cable discs, please?

[Brucey]

it is not possible to make comparisons without a specific brake to compare it to, but the BB7s primary advantages over most other cable disc brakes are

1) the CPS system, which allows the brake caliper to be aligned correctly even though the disc mounts have not been faced

2) a basically robust design; yes it is not perfect (see previous comments) but it is better than most others. It is considerably simpler internally than (say) a Spyre for example, and is less likely to give trouble through water ingress.

3) the pad adjustments, which are simple and effective


The Avid BB5 (and earlier calipers which were known as BBs, BB3 and so forth) share the basic design of the fixed pad adjuster, but are less easy to adjust in the moving pad, and use smaller brake pads (that wear faster), a different retention system and so forth. The BB7 represents a logical development of these designs.

I am told that the BB series of brake calipers is manufactured for Avid (SRAM) by wellgo, who are better known for their pedals (they make lots of other pedals for other folk under other brands too...).

cheers

[frankly frankie]

Avid levers (for flat bars) are also exeptionally good (adjustable leverage) and inexpensive.

Advantages that the Spyre has over the BB7:
* easier (even easier) to set up and get centred on the disc etc.
* easier (even easier) to adjust using just fingers.
* much lower profile, they sit more inboard compared with BB7s.  May improve luggage clearance.
* 'standard' Shimano-fit pads, so lots of after-market options available.

However nothing alters that the BB7 has more bite, with less lever pressure, using similar pad and rotor materials.

Other disadvantages of the Spyre:
* it's touted as a drop-in replacement for the BB7 - it isn't, the Spyre sweeps a bigger radius than the BB7, by at least 2mm.
* the pads are a sloppy fit (though secure) in the caliper body - it doesn't really effect braking but it just feels naff, like a rim brake with a loose bolt - and it does make it impossible to check for play in the headset by rocking on the front brake.
* probably the rotor will heat up more, in any given braking situation (because the pistons are insulated to prevent the caliper getting hot).  (However I have used my Spyre-equipped loaded tourer in the Alps without any heating - or other - issues.)
* two moving pistons, so more to go wrong in theory.