Bikes Touring Bike FAQ

Touring Bike FAQ #4: Disc Brakes or Rim Brakes (V‑Brakes)?

This is #4 in an ever-growing series of answers to frequently-asked questions about touring bikes. If you’re new here, why not start with #1: What Exactly Defines A Touring Bike?

While many high-end touring bikes are nowadays fitted with disc brakes, there’s still plenty of debate over whether V‑brakes or disc brakes are actually ‘better’ for touring. 

And, as usual, there’s no clear-cut answer. I’m sorry about that.

V‑brakes, for the purposes of this post, are a generic and misused term for the several varieties of caliper brakes that work by pinching the bicycle wheel’s rim between two brake blocks to create friction and slow the bike.


Disc brakes on touring bikes are relatively new, appearing gradually on mainstream touring bikes over the last decade or so. 

They were originally hydraulically actuated, having been modified and transplanted from motorbikes for the high-end mountain biking market. 

Later, cable-actuated disc brakes appeared, using the same steel cables, housings and levers as V‑brakes. All disc brakes are characterised by having calipers that act upon a metal ‘rotor’, or disc, which is bolted onto the wheel hub. The braking surface of the wheel rim is not used.


The big debate originally arose because disc brakes were a departure from traditional established touring bike design, which exclusively used cantilever or V‑brakes acting on the wheel rims. Tourers are generally reluctant to risk the reliability of their rides on new-fangled technology.

As the years passed, however, several models of cable-actuated disc brake started to prove their reliability on a growing number of round the world rides, with the TRP Spyre series seen most frequently.

That they are now fitted as standard on some of the most popular touring bikes available is a reflection of the fact that disc brakes have crossed over from ‘new-fangled’ to ‘tried and tested’ – as well as there being several objective advantages to using disc brakes over V‑brakes on tour.

The case for disc brakes on touring bikes

Disc brakes’ advantages over V‑brakes mainly lie in their braking functionality. They offer a finer degree of control over braking, known as ‘modulation’. All else being equal, they can also provide slightly more stopping power. With fully-loaded touring bikes easily weighing three or four times the weight of an unloaded bike, the prospect of an increase in braking power is a tempting one.

For ultra long-term tours, disc brakes offer another perceived advantage: they won’t wear out your wheel rims. It takes far longer to wear out a disc brake rotor with disc brakes than it does to wear out a wheel rim with V‑brakes. This is accentuated in wet, dirty conditions when grit and crap on V‑brakes will grind away at wheel rims like sandpaper.

In the long term, using V‑brakes will more or less guarantee that you’ll need to replace the wheels of your bike, or rebuild them onto new rims, at some point (you will get plenty of advance warning of this if you keep your eyes open; most good rims feature wear indicators for just this purpose).

Most long-haul tourers seem happy enough knowing this, and plan or prepare accordingly. They also know that a wheel is as likely to need rebuilding because of snapped spokes or worn-out hubs as it is because of a worn braking surface.

The case for V‑brakes on touring bikes

In this light, it’s easy to see V‑brakes as an old-hat, low-budget, sub-optimal choice for braking. But this is not true.

The braking power argument is often given undue importance. It might well help a downhill mountain biker win a race, and that’s why mountain bikers love hydraulic disc brakes – but that’s very different to 99.9% of the scenarios a touring cyclist could expect to encounter.

We’ve all ridden bikes with crap V‑brakes that are poorly installed and badly maintained, but a properly-adjusted set of modern V‑brakes can deliver a similar level of raw braking power to a cable disc brake, given due care and attention.

So that’s why you’ll still find V‑brakes fitted to tourers with price-tags well into the thousands of pounds. At the end of the day, they simply work. They’ve been doing so since bicycles were invented.

Rim brakes have one huge advantage for the long-haul traveller: compatible parts can be found in one form or another on almost every bike on the planet, whereas disc brakes still rely on non-standard, proprietary brake pads and calipers.

Rim brakes operate upon the simplest possible principles, and if kept properly adjusted they’ll do the same job of stopping a fully-loaded touring bike that they’ve been doing for decades. There’s a huge amount to be said for that simplicity.

As with so many noisy debates in touring equipment choice, then, the underlying point is easily forgotten. And in the case of brake technology, the more important question is not whether rim brakes or disc brakes are ‘better’. At the end of the day, they both stop bikes.

The real question is which would be more appropriate for your tour.

Tackling lots of big mountains and/or dirt-road bikepacking in the short term? You might well benefit from the increased control and power of disc brakes.

Riding round the world for the next few years? Your priorities are likely to be better served by the simplicity, durability, ease of adjustment and the availability of spares that come with V‑brakes.

Next in the Touring Bike FAQ series: Derailleurs or Internal Hub Gears (Rohloff)?

86 replies on “Touring Bike FAQ #4: Disc Brakes or Rim Brakes (V‑Brakes)?”

Not mentioned above, there is a huge disadvantage of cheap disc brakes, like the Tektro Mechanical Disc brakes that came on my Specialized Roll, and which are also the norm on countless low budget yet name brand bikes like by Specialized. The disadvantage is that the pads glaze over very quickly, especially in the mountains. Quickly as in, a brand new set of pads will become practicly useless after a single large steep mountain descent. I never had an issue like this on the vbrakes to my various $200 Walmart mountain bikes. Their pads lasted 10x as long, or more. Metal pads, and much larger rotors such as on disc brakes for downhill bikes would be better for bikepacking in the mountains. Unfortunately they will cost you 10x to 50x as much as v‑brakes.

Hey Scott! Thanks for the comment! The only time I’ve experienced disc brake pads glazing over in the way you describe is if they are not properly bedded in from brand new. It’s common when fitting new pads to follow a simple process of intermittent braking on a mild descent to take off any surface glaze. It’s also a good idea to clean them with brake cleaning solvent in case there are any contaminants on the surface. The same technique goes for new disc brake pads on a car. There’s a good tutorial on Bikeradar on how to do this. Hard braking and the consequent overheating a brand new set of pads without bedding them in can produce the effects you’ve described here. This doesn’t necessarily apply to your case as I don’t know the details, but I thought I’d share this tip here for reference anyway. Cheers!

Potential deceleration on a bike is about 4 times acceleration. Stress on front wheels will multiply accordingly. Having tried several of the bicycles on offer in the USA whilst visiting I wouldn’t recommend that anyone over there touch disc brakes (as main brakes) with a barge pole — or even touch these bikes. My recommendation would be, start again, set it up to accommodate derailleur gears and V brakes, I’m sure there are prefessionals in Canada, UK and the rest of Europe who can offer advice.

Hi Daniel. I appreciate your concerns about potential wheel stress. But there’s no inherent mechnical issue here – after all, motorbikes have been running disc brakes for decades, and the stresses in that context are far in excess of anything a pushbike could manage. Indeed, this is where hydraulic disc brake technology for bicycles was borrowed from! Using the correct spoke gauge, lacing pattern, tensioning, and many other wheelbuilding factors is of course important. However, as for your generalised warning, I do feel I should cite as a counterpoint the thousands of people who have been riding disc-equipped touring bikes without any issues in real-world scenarios for many years. Mine have more than a decade of use on them, as do the wheels they’re paired with, and are still going strong today.

I appreciate the opinions and experience here so far on the topic of “V brakes” vs disc brakes. I’m going to throw a different perspective in for consideration: How does hand size and grip strength affect choice of brake on a touring bike? Is there a real mechanical advantage to one or the other type? Let’s say on a long relatively steep downhill fully loaded in fair weather.

I would venture the opinion that, in general, the more noticeable difference in terms of braking action is between hydraulic and cable-actuated brakes, not discs/rims. In other words, a well tuned Magura HS33 rim brake will provide more power and performance than a badly installed low-end disc brake. I’d also say that if V‑brakes weren’t up to the task of long steep fully-loaded descents, people wouldn’t use them. Just pack some spare pads and keep them well maintained and you’ll be fine!

I have used both good Campy Record road brakes on Pikes Peak and Mt Eveans in Colorado to the Going to the Sun road in Glacier National Park and going over the Teton’s with a 100 lbs of gear on a fully loaded tour bike with TRP HY/DR hydrolic/mechanical, disc brakes. Going down Pikes Peak the rim’s got pretty warm on fairly new break pads. Going To The Sun and crossing the Tetons. No issues what so ever. Plus the TRP HY/DR breaks where very easy to feather the grip pull so my hands never got tired, sore or cramped. I can’t say the same on Pikes Peak and Mt Evans. Those two roads have no place to let up. You are either flying or breaking hard. Just my humble opinion.

I have three bikes with three brake systems.
Hydraulic disc on my steel hard tail MTB (Niner Ros 9).
Mechanical disc on my touring / packing bike (Surly Bridge Club).
V brakes on my “road bike” and most recent purchase (Surly Cross Check).

I’ve packed / toured on the mountain bike, I’ve ridden single track descents on the touring bike, and have done just about everything from gravel, road rides, packing and international touring on the Cross Check.

The main reason I went with V brakes on the Cross Check instead of disc (Surly Straggler) was because when I was touring around Taiwan (on the Bridge Club), my front disc was bent in transit and I had to get it fixed. Fortunately Taiwan has a huge bike culture so it wasn’t an issue. But the idea of V brakes for a bike I was planning to tour northern Thailand on next, just felt like a solid and simple plan. So admittedly that factored into my decision.

While I agree with the compatibility advantages of V brakes in some less developed countries, I also agree that whatever the brakes, if you take care of them, service them, pack properly for transit (which I didn’t) you’ll be ok. 

If you’re running disc in a third world country and need to switch to V for reasons unknown, a local welder can get the job done. You won’t be stranded there, you’ll figure it out and you will get home.

The main point I want to make is that you as the rider simply adjust to the tool you are riding. I’ve never liked any bike I first sat on, and then 100 miles later I can’t imagine riding anything else. I think this is why I go through phases of riding each bike. I just took my touring bike on a single track MTB tour through Idaho because I just didn’t want to switch back to my Niner that month and I felt like having more gears. The disc brakes may have had a little less
Modulation on the down hill, so I simply adjusted the most adjustable component of the whole bike; Me, and it was just fine.

So, it’s neat that we have such refined options available to us which are prone to long debates of which is better and why, but when my novice bike friends are buying a their first new bike and ask me which is better, I usually tell them that all modern brakes will get the job done fine. Sure, do your research to help make the decision, but there is no wrong answer in my opinion. Take care of your bike, and it will get you anywhere. 

My good friend tours on a bone stock late 90s REI shop brand MTB bike (Navaro). He keeps the drive train clean, replaces the chain every so often, but it keeps on ticking. My bike is a little fancier and lighter than his, but he packs a little lighter then me and easily makes up the difference.
Even though we love complicating things, all in all, bikes are pretty damn simple.

In fact, I’m going to stop typing and go ride my bike right now.

Most of the comments received argue for one or another type of brake. Why not both? Each has advantages in varied circumstances, the weight of a second set of brakes is negligible when compared to the overall mass of a loaded expedition bike, and the added reliability of the bike is enhanced. Yes, things do get busy on the bars, but so far, I’ve had good luck using both disk and vee styles on the same bike at the same time. Now if only I could figure out how to run two sets of drivetrains…

If so much discussion is needed to compare the new technology with the old one, that means that the old technology was better. When new technologies are better, they are adopted instantly. 

Also during the last 20 years I rode v‑brakes. Never put my feet in bike shops. During the last 2 years I rode disc brakes. I had to let some bike shop guys touch my bikes 4 times. I hate that. I am so happy I didn’t scrap my old v‑brake bikes ! I will keep them forever. One steel, one aluminum. Mountain bikes, not touring bikes. Bye bye bike manufacturers !!! See you in the next life.

Thank you so much. I am just building a bamboo touring bike at the moment. Total newbie, having done short tours (2 weeks or less) on either full sus mountain bikes or dutch uprights — because that’s what I’ve had available to me. I am loving the steep learning curve, thank you for all the input. 🙂

I’m thinking of going touring around Thailand-Laos-Vietnam. However, this will be during the rainy season in which I am told it will typically rain heavily, but only for short periods in the day and the rest of the time it is fine. My concern is having enough braking power in the mountains if I get caught out in the rain, but not being able to find replacements if something were to go wrong with disc brakes (especially in Laos). Does anybody have any suggestions or experience over there during the rainy season?

Note: Because of how cheap it is over there I wouldn’t need much stuff and should hopefully be able to have everything I need at around 30kg or under (including the bike).

Rims fail while hubs last.. and its not always easy to tell how far gone a rim is so you end up replacing them sooner than later to be sensible. So less metal to chuck away and a bit more confidence in your bike on the longer road. I agree also.. with a small adjustable you can true a disc rotor quite easily.
I’ve only recently come to this conclusion and it’s having rebuilt a wheel for the third time, same spokes and same hub and chucked away another bit of metal. V brake pads wear out fast and I like the extra braking in the wet with a loaded bike. 

From experience I don’t think it’s that easy to know quite how far gone a rim is so you end up replacing it with less wear to be sensible when touring in remote areas and hubs tend to last.. it’s the rims that fail. Also I’d like to reduce the amount of consumables and disc pads last much much longer than v brakes and don’t eat your wheels. So a bonus having less metal to chuck away.

A really excellent thread!
I am about to pull the trigger on a new frame for mixed touring purposes (on road/off road) in the Tirolean Alps where I now live.
I have several bikes — A Giant Anthem 27.5 with upgraded Zee Downhill hydraulics, a Gunnar Roadie road bike using rim operated Ultegra and an old Klein Pulse using V brakes (this is the bike I am about to replace). I have been contemplating for over a year now what it is I want. The Giant is great for my pure off road rides with extreme alpine descents, but these are extremely fast downhill — 1000m+ descents. My road bike I actually do not enjoy riding anymore due to the 25mm tyre restriction and the limitation to tarmac. So I am now mostly using the Klein, which has other inherent problems due more to geometry than anything else.
I will replace the Klein with an Oxford Bike Works 26″ using V brakes. This I believe will offer me more than adequate braking on/off road for the thing I want it to do — touring, day tours/2/3 day self supported. I am not racing, I am enjoying myself. The Giant braking power is great but this is a 13.5kg machine on extreme downhills taken at extreme speeds (60/70kmh) and even then after 1000m descended you need to have a break to let the discs cool. They are a pain to maintain, need frequent bleeding and pad replacement (twice per season), and the rotors do deform and need frequent tweaking. Even the Ice Tech rotors and finned pads take a hammering and are not what I expected.
So, for me the simplicity and relative long life of rims V brakes and pads (rims are now 6 years old and holding up well, I change pads once a season) will give me the ideal set up.
As mentioned before, it is all about analysing what you are using your machine for.
If I were to (and I hope to one day…) undertake an extreme tour I would use the V brakes every time.


It just happens that Tirolean Alps is one of my favourites destinations that I visit. For the past two years we did lots of road cycling in that area. We built the bike for my friend based on Focus Mares CX cyclocross carbon frame with Hayes CX‑5 mechanical disc brakes and Shimano Tiagra 4700 components. The bike was fitted with Specialized 700x30C Espoir Tires, custom 48x32 crankset and 11–34 cassette. It seems to be a winner. For hard alpine ascents it has 32x34 lowest gear on which my friend climbed Rettenbachferner, Stelvio, Kaunertal, Kuhtai and many different climbs. He did thousands of kilometres over last two years including some rough off road in Czech Republic (Rychlebske Stezki) and so far he didn’t change his pads even once. 700x30 tires are good for both road and light off road use. He usually pumps around 80 PSI which gives enough comfort. Braking is very good and predictable.

Thanks for the info. I am not really a fan of carbon, I am a bit rough with my bikes. The terrain is off/on road so a bigger tyre is a must. I guess I am looking for a happy mix of durability and simplicity. I want to carry some luggage and mudguards are essential.

I just love this posting. It is like weather you like a Chevy, Ford or Dodge.
So here is a short review of my tour bike set up with the TRP HY/RD brakes. They have been outstanding for me but my touring extent has been in the USA and not in a different country.

I am running a pair of TRP HY/RD brakes on a Specialized AWOL Elite, touring/commuter/just all out fun riding machine. Almost 4,000 miles currently on this set up. 1200 miles riding PCH 1 this summer with just over 100 lbs bag weight. Let me tell you these brakes work with confidence under all situations. Even at 48 mph 14% grade coming to a complete stop (in a hurry) while touring PCH 1) These brakes defiantly saved my life. Great modulation. You need to use compression less brake cable housing. I used Jagwire Ripcord Brake Kit, Titanium, Hope 160mm Sawtooth Floating Rotors front and back, Avid Speed Dial 7 Levers mounted on Jones Carbon H‑Bars. A great set-up for touring and we’ll all other riding. I am thinking about getting another set for my Fatback fat tire bike also with Jones H‑Bars. I have had zero break maintenance at 4,000 miles. Highly recommended. I did contact TRP about using these on my Jones H‑Bars and they did not recommend it. They said they were designed to wrap around bars only. I did not do the install. They were installed during the bike build by a LBS. These are the second generation brakes. I have had to tear down the bike twice for travel by train and air plane. No issues. Just packed the bike as I always do with spacers between the forks and padding on the bottom.

I have never understood how people burn through brake pads quickly on disk brakes outside of the down hill mountain bike world.
Granted, on this forum I am an outlier in that I don’t do loaded touring, but I do a lot of loaded commuting and have done so in all sorts of foul weather which should induce crazy brake wear (southern Ontario winters).
My touring bike which gets all sorts of bad weather but no salt as of yet has about 9000km on the original pads with no visible signs of wear while my crappy beater has well over that on a single set — including four winters. The only time I had to replace a set of pads on it was when I accidentally got rust proofing oil on the front pads — that did them in. But road grime, salt, water, mounds of snow, slush, muck, and all that did nothing to hamper pad life and virtually nothing to hamper brake performance. Compare that to riding like that with rim brakes where sometimes ONE stop kills a set of pads… (happened to me twice in the winter).
Granted, most don’t ride in those conditions, but it is telling to me that dirt cheap disk brakes (Avid BB5s) will go that far through that much crap on a heavy bike with heavyish bags on it with zero maintenance.
Modulation on both bikes — beater with flat bars and touring bike with drop — is perfect.
As an aside my cross bike, now sold, was a Jake the Snake with Cantis on it. Its brake performance was dismal in comparison to the disk braked touring bike. Not even close. Seen in isolation, the brakes were great, but not when ridden back to back against the much much heavier tourer which could stop in a significantly shorter distance.

And I wonder why most of the new models made specifically for big expeditions by credible brands like Ridgeback are now moving to disc brakes e.g. the new model of Ridgeback Expedition 2017 model has got disc brakes ?

If you want to try both brakes (without having to buy a new bike) get a frame that has mounts for both like the 2016 Soma Saga DC or Thorn Nomad. 

Heck, if you feel Murphy’s Law is on your ass a little too much, you could actually install disc and cantis on these frames. Run one set to your aero levers and another to CX levers. 

I know a person who went from rim brakes to discs after heating up his rims on a descent and exploding his tube (yes, he crashed)—- and he knows a guy who went from discs back to rim brakes, because of a frustrating mechanical out on the road.

Oh, I forgot to ask: What about drum brakes for touring?

These days Sturmey-Archer is offering a bigger size model (9″ instead of the usual 7″) and even a drum brake + generator hub model. 

AFAIK, drum brakes work very good under rain and require very little maintenance, and their pads are also very long-lasting. On the other hand, they are heavier. 

Can someone write about their suitability for touring bikes? Thanks!

The folks at Rodríguez Bikes have a very detailed page about why they prefer cantilever brakes instead of disc or even V‑brakes. After their 4‑decades of experience building touring and tandem bikes, they summarize their preferences like this:

Disc brakes:
+ Work well when riding into water streams.
+ Work well with bent rims.
— Are heavier than other kind of brakes.
— Require heavier, reinforced forks.
— Can overheat and get warped easily, thus making loud scraping noises.
— Brake pads and rotors are not easy to find in remote areas.
— Make a more difficult work to pack/unpack the bike when travelling.

Rim brakes:
+ Lighter (up to 2.25 lbs / 1kg than a disc setup),
+ Cantilevers offer easier modulation AND lots of braking power,
+ Even top-notch models are cheaper than disc brakes,
+ Longer brake pad wear,
+ Brake pads are cheaper and easier to purchase anyplace in the world,
+ Brake pads are easier to replace,
— Can’t work with wet or dirty rims,
— Can’t work with bent rims.

I’d recommend to read their website to get more insight about this subject:

Largely true, which is why disc are better for MTB. However that was written over a decade ago and since then disc brakes have surpassed rims for power and modulation. Plus heat dissipation has greatly improved. 

And they forgot to mention rim wear when using in grimy muddy conditions. I have got through rims in one season easily when using in those conditions. 

Alos to be fair, rim brakes do work in the wet, but not as good as discs, which hardly seem affected. 

Plenty of spares if touring Europe.

Personally I would still use rims for road touring, as it saves weight and they are more than powerful enough. Plus I don’t need as much modulation as I do riding my MTB in slipping conditions like a steep muddy descent, where the modulation of a well maintained (bleed and silicone greased up) modern disc brake really comes in. 

Not so sure what was meant about storage, as modern disc

This article was written in the early days of hydraulic discs for mtb. Having used v brakes a lot and discs since those days, I can vouch for how much discs have improved in that period. The Shimano ones are now very reliable too. 

The fact that discs are recently an option on high end racing bikes, shows how much they have come on.

I guess with storage / transportation — the article meant 2 things 

a) discs can bend easily
b) if you pull the lever a few times when there is no wheel in it will cause the discs to seize up and they can be tricky to pry apart.

in reality this has has no proved a problem. you can quite easily remove the discs (6 bolts or even easier for center lock, one screw) — for transporting on a plane. and if they do bend they can easily be bent back with an adjustable spanner by eye. Or even bent back using your fingers (clean the disc after or use gloves ).

To stop the pistons locking up, a cheap spacer can easily be inserted between them. This is designed for the purpose.

I’ve done both of these things. A bit of cardboard is a perfectly decent spacer. The adjustable spanner method works well if you’re careful. Modern bike tool kits often now include a disc rotor truing tool…

1) The first thing that has to be stated is whether we are talking flat bar MTB bikes, or drop type road warrior touring bikes. If the former, suit yourself, there are tons of options on the disc side, and most riders, certainly recent generation riders prefer them.

If we are talking bikes with drops and road levers, and price points roughly equivalent to the cost of a cheap touring bike on down (for the brake system alone), you have no great options, and discs will not do much good. The reason is the greater modulation and power of discs is mostly the levers, once you adapt levers to drops, you will not get the performance of MTB Hydro with anything. That is the real reason why cantis remain popular, they are the best adapted to the drop touring bike of the caliper/non disc, lightest, work on wobbly wheels, make mounting racks as easy as it gets, etc…

Number two thing you need to consider is whether you are swimming through mud or just riding the roads. The real situation where discs are supreme is in mud. The reason we are seeing discs on road bikes is: They aren’t road bikes, they are cross bikes, so mud is a factor. Demographics. If you can sell them they are much higher end and maybe more profit.

If your touring is all dry and clean, discs are not a clear option.

Cantis do work on wet rims, you need sintered blocks which are not as nice all around, but might be worth a try on say an Irish trip. Cantis work fine on wobbly rims, not as well as if not wobbly, but they work ok. Vs do not, so that is another thing in favour of cantis.

One thing I think about at 74 inches and 250, is that I am in the tandem weight range, and what I really want is 3 brakes with a redundant system. They do that on tandems with a drag brake. My personal preference is double front brake, possibly a canti + disc option as many bikes allow that. This covers a lot of bases. You only have the bad features of a disc like weight and rack problems in one place. and you have the advantages where the do the most good. Use three levers and have the canti on the tops so you have an additional position for braking. Double caliper is another option.

Regarding rack problems and disk brakes. It can be a fun one, that is for sure. On my Sutra, it has turned out to be a non issue for the rear end — designed right, as the Sutra is, any rack will fit. The rack tab is above the brake area, and the calliper is inside the rear triangle. If you are thinking of a bike with disk brakes, that should be the location for the brake or racks will become a problem. The front is more of a concern for rack fit but I have found that a Surly Nice Rack fits perfectly with zero brake concerns. The Blackburn low rider rack that the bike came with also had no problems clearing the front calliper (I got rid of it — did not like it much).

So I am a newbie to touring bikes. I am building a new touring bike. Starting with the Specialized AWOL Expert frame. The wheels are Velocity Dyad rims. Rohloff on the rear and Son 28 on the front. Gates Carbon drive. 180mm disc front and 160 disc rear. What I am having trouble deciding on is mechanical vs. hydraulic Disc brakes. What I originally wanted to use was TRP HY/DR but since I am using a Jones Carbon H‑Bar I will not be using road levers. I email TRP to ask about using the HYDR on Jones Bars and they said NO. They are made for road style levers. So I am considering using TRP Spyke mechanical or Shimano SLX hydraulic or TRP Dash Sport hydraulic. As I stated above my struggle is between mechanical or hydraulic. At the moment my touring will be in the USA. Planning to ride the Seattle to San Diego PCH1 route this summer. My only experience with disc brakes is BB7’s on my Fatback fat tire bike. They are adequate for winter and summer fat tire riding. SO I would have to learn how to take care of hydraulic brakes. Hey you got to learn sometime right. I would like to hear your thought on this. Mechanical or Hydraulic?

I’ve used many types of brake and ride 5000 miles a year on average. Shimano SLX brakes are very reliable. More powerful than the BB7’s I used. They are also easy to bleed. They use mineral oil, which is less harmful. Plenty of instructions on youtube. They are very hard to beat. I’m not sure of mineral oil availability if touring in some countries. That’s the only possible downside I can think of.

Other theoretical disadvantages of hydraulic brakes for touring include the difficulty of repairs and the proprietary nature of spare parts in the case of component failure or accidental damage (for example a brake hose being ripped out during transit or a lever being snapped in a crash). One advantage of cable-actuated brakes is that – with the exception of the caliper itself – parts are often interchangeable with bog-standard V‑brakes.

I would like to expand on the power question mentioned above. All things being equal (namely, comparing cable actuated v‑brakes and disc brakes), the power of a properly maintained v‑brake on a 700c rim will be 300% greater than an 8″ disc brake! It is equivalent to trying to remove a stubborn bolt using a tiny 4″ wrench (the radius of an 8″ rotor) and a 12″ wrench (the radius of a 700c wheel, which is, after all, a disc). Physics and leverage. However, cable disc brakes can be powerful enough for single bikes and they bring other advantages (although I’ve never been too impressed with them). Now, because hydraulic fluids can transfer the power from the hands much more efficiently than cables, hydraulic disc brakes change that equation, although I’m not sure by how much. The most powerful brakes will be the Magura hydraulic rim brakes — hands down. But then we still trash our expensive rims which is why hydraulic disc brakes for mtn bikers is a win-win. For touring, I think it is a toss up. Santana is a well known tandem bike maker and they talk about why they use v‑brakes for their front rims and disc for the rear. Their tests have shown that disc brakes just are not powerful enough for the critical front rim. For the rear, on the other hand, we tend to squeeze those brakes harder for the entire duration of the stopping action which can generate a lot more heat than the front — so they go with discs in the rear to avoid tire blowout. I think those principles could apply to heavily loaded touring bikes.

A couple points: It’s a Cr-Mo loaded tourer — use the biggest rotors you can fit — there is no penalty for having excess braking capacity. Also, use the same size front and rear. While it’s very unlikely you will ever damage your front rotor and have to swap them in an emergency, especially on PCH, it’s a touring way of thinking and it’s a touring bike…
And while there’s no disputing taste, I sure wouldn’t put a $300 carbon bar on a $700 Cr-Mo frame (unless it was lying around the garage.) Experiment a little with cheaper alternatives (including drop bars).

I am not sure I might have posted my comment in the wrong spot so I am posting it again here hopping it gets to those that made comments.
Thanks for all of the input guys. All is greatly appreciated and I have read and listened to all of it. Thanks again. It has been a long process to get this bike built. As you know they can get kind of expensive. It is in the final stages and could be done this weekend. In the end I am going with the TRP HY/DR disc brakes. I figured out how to make it all work out even with the Jones H‑Bars. As far as using the carbon version. I currently have the aluminum version on my Fatback fat tire and love them to death. I have carbon drop bars on my cycle-cross bike and road bike and appreciate the road vibration elimination so I am hoping that come through on the new tour bike. I am also going with 160 mm disc both front and rear for the reasons stated in the comments. “Keep the disc the same”. I am looking forward to putting this bike to good use and many miles. A couple of months ago I had my Bianchi Sempre road bike in for its 20,000 mile overhaul. It is a full carbon, frame, handle bars, seat post bike with full Campy Record 10 starting/stopping. Even as a carbon bike it has held up great with only tires, tubes and two chains. Everything else is original and still running so I have a lot of confidence in the use of carbon for the John H‑Bars. Know to just get everything finalized for the trip. I just travel arrangement today to get me from the Twin Cities, MN to Seattle, WA and from San Diego, CA to home. It should be a great trip. Thanks Again for the comments. Anything new is a bonus.

1. Higher torque (more braking power)

Of course not. This would mean an 80mm disk would be better than a 160mm disk and a 40mm better still! That would certainly upset the laws of physics!-)

2. Stiffer braking surface Aluminum rim vs steel disc

True, you can select a better surface than aluminum. (Although I’m surprised it’s stainless steel, given the bad results with the old steel rims.)

3. Better cooling (less fade)

Goodness no! The pads must deal with 4x the force/friction and are much more vulnerable to glazing. The smaller disks can get very heated and warped.

4. No heat at the tire bead (safer)


5. More modulation.

No. Since rim brakes require less force, you can match the mechanical advantage of the disk brake lever and then match the “heavier” feel by adding a resistance spring. It’s a waste of energy, but, hey!, think of the modulation!

6. Longer life of components, no rim wear

I doubt it. The pads are facing much more abuse and I’m not sure that steel makes up for the higher (hotter) forces on a smaller surface of the disk. From a quick look, it appears an Avid replacement disk costs the same as a Sun CR-18.

8. Less accumulation of foreign materials (water, mud, etc)

True — making them an excellent second purchase after you put fenders on your ride;-)

On the subject of brake pad wear on disk brakes. My current banger bike has a set of Avid BB5 brakes on it. The bike is used for commuting all year round (some years see more km than others). Most of the bike has been replaced, but not the brakes. I suspect that the brakes have about 9000km on them but that is a guess.

Currently, the brakes have 4 winters on them with the original rotors and original pads. Last time I checked, the pads are still fine. I have not cleaned the rotors, not dealt with any bent rotors, nor have I had any brake failure or fade or strange sounds from them. They just work. Every single time. 

Granted, winter riding introduces different stresses on brakes than touring does, but speaking personally, I find it hard to accept arguments that disk brakes are somehow inherently less reliable than rim brakes just because they are disks, based on the experiences I have used cheap as dirt mechanical disk brakes in. 

In fact, in the conditions I ride in, rim brakes are often significantly less reliable. There are times when one stop equates to one set of brake pads destroyed (did that twice in bad weather).

Again, I am talking about abusive commuter bike riding in really foul weather on icy, gritty, salty roads.

My touring bicycle is a 2014 Kona Sutra, again with mechanical disk brakes (Hayes ones) which, after 8000 plus km in all but winter conditions, have no appreciable wear on them and zero problems with stopping, even fairly heavily loaded down. I have, however, had to replace the front chain ring, cassette, chain, and wheel set (not built properly and suffered from rim separation) in order to keep the bike rolling. But the brakes? Total non-issue.

Again, I must stress that the bicycle is used as a longer distance commuter / gravel road / explore bike and that I do not do actual touring with it. I mention my experiences only to offer a perspective on disk brake reliability when abused heavily over time (particularly on the commuter bike which, poor beast, just gets ridden and largely ignored except for the odd bath and drivetrain cleaning).

Note: @Dan Gao
This was meant to be a general comment and not a reply to your post per say. Cheers!

The most salient difference between disk and rim brakes is that the “disk” of a rim brake is twice the diameter of the typical disk brake disk. This means the disk brake requires twice the force to achieve the same braking torque of a rim brake. The only ways to achieve this are: higher friction pads and disks; stiffer (so heavier) parts; higher mechanical advantage in the levers and calipers — so more grip force over longer distances. The latter is euphemistically referred to as “modulation”. And indeed it might be useful in gently scrubbing speed in a pack. But it only hurts when trying to stop a loaded tourer.

The oft repeated claim that disks are better in the wet may be true. The higher pad forces and isolated disk surface perhaps give better performance. But I’d sure like to see some experimental confirmation given how badly the basics are misunderstood.

Interesting point about the diameter. Don’t forget discs are often hydraulic so they will get more force in that way. Plus my BB7s (mechanical disc) with new clean cables are not far off my Elixir 5s (hydrolic) in power. BB7s have more power than my lx v brakes! 

What I imagine explains this is that the pads in BB7 move only a small amount compared to the v brake pads when you pull the lever. Yes you have more modulation in theory with the mech disc, but it’s geared differently for more power, so the modulation and power end up the same.

First apologies for writing off the top of my head and confusing the 6–7 inch diameter of a disk for its radius. Actually it takes 4 to 5 times as much force for a disk to stop like a rim brake. On another site I saw an Avid engineer acknowledging this. This does mean that disk brakes are inherently 4 or 5 times less powerful than rim brakes, as power has a precise definition. I don’t want to dwell on that, because power isn’t important after the first g of deceleration.
Hydraulics might reduce friction and make the system stiffer, but they cannot transmit any more force than a cable and housing (short of failure of course;-). Their big advantage is that one can engineering any kind of mechanical advantage into it by varying the diameters of the pistons at each end. This is important for disk brakes which need the large MA that can be difficult to design in simple hand sized levers. And if they were that good, we would see a lot more Magura rim brakes!-)

the great point with discs if that you vary the diameter. Whereas with rim brakes you are stuck with the wheel size for your frame. Personally I have used discs ranging from 160mm to 200mm.

You def feel the extra power as go up to 200mm. The main advantage is that it is easier to operate, less effort. Can one finger brake if you desire. With hydraulic or even cables with a 200mm it’s way more than all the v brakes I have tried.

The disadvantage is that you lose feel / modulation. 

I tend to stick to 160mm for that reason as I don’t 1 finger brake.

As I have said before, there is a large difference between V brakes and cantilevers. The braking forces are different in addition to many other differences like fork stresses, cable pull and modulation. V brakes tend to be more on/off as opposed to the modulation that cantilevers offer. BTW, modulation (variation) is the ability to apply more or less force to the braking action as needed or required. Also BTW V Brake is a name invented by Shimano for liner pull brakes that have been around a long time. 

Now to disc brakes. Ask yourself why motorcycles don’t use rim brakes (really disc brakes also) as they once did. They changed as did autos because of the superior braking provided by disc. So, why do disc provide superior braking? Simply, disc brakes provide:

1. Higher torque (more braking power)
2. Stiffer braking surface Aluminum rim vs steel disc
3. Better cooling (less fade)
4. No heat at the tire bead (safer)
5. More modulation.
6. Longer life of components, no rim wear
8. Less accumulation of foreign materials (water, mud, etc)

These are just a few of the advantages of disc brakes. As to cons, they are heavier but remember if you use disc rims the revolving weight is moved inward and comes very close the to same. Also remember that the weight argument was used when brake lever shifters introduced. Seen a downtube shifter recently? 

Most of the arguments against disc brakes are the same as when cars first started using them. They were not true then and are not true now. If you would like a more technical and less emotional discussion read the scientific studies. It is amazing what you can learn. They discuss torque forces and such, very in depth. 

If you are looking for improved touring braking over v brakes (liner pull or direct pull) and do not want to expend the money required to change to disc go to something like Paul or other high end cantilever brakes. You will not believe how much your braking will improve. 

I have been touring for over 35 years covering more than 63 counties and am a retired bicycle industry professional.

Interestingly, the 1966 TT winning Honda 50 was equipped with bicycle-style rim brakes. Lightness was the main consideration at a time when the alternative was a rather heavier drum brake.

I find a good hydraulic brake with a smallish disc is better than all the v brakes I have tried in terms of power and modulation. I have not tried XTR though! The disadvantage is system can overheat more readily on long descents. A rim brake uses the whole tyre to cool down! Whether this is your disc or the fluid that boils depends on your pad type. I use sintered pads and they cause the disc to overheat before the fluid boils. It rarely happens if modulate the brakes and you do yet a warning first with reduced power. I have fitted a quality disc (XT centerlock) which helps a lot.

I have several bikes. Road endurance (Campagnolo Centaur, caliper brakes), road race (Shimano Ultegra, caliper), hybrid (Shimano Tiagra, mini v‑brakes), cross (Shimano SLX, hydraulic discs), trekking (Shimano Alivio, v‑brakes), recreational MTB (no name, v‑brakes), race MTB (Avid Elixir, hydraulic discs), old school Cro-Mo cross (canti).

The advantage of hydraulic disc brakes that I see, is in few conditions. Using high speed on long descents and in wet conditions. So if you do a lot of hilly rides with long descents you might be safer on hydraulic discs. Also if you ride during winter or rainy spring/autumn, especially on paved surface and you have to stop quickly. Another advantage is on races or group rides when something suddenly happens in front of you or you need to go down on very steep descent in cross country ride or race. Then you will have more control and there is less chance of locking wheels when braking. Rim brakes (V‑brakes, caliper, canti) have to clean the rim dry before braking starts and this lag might be of high importance in such situations. Especially in motorized traffic. In wet, the braking distance for rim brakes is much longer than disc brakes. In dry conditions there is not much difference.

For most cyclists rim breaks are better choice. Especially for those who change or take out wheels and tires often. It takes few seconds to adjust caliper or v‑brakes unless you put the wheel with different rim with. Adjusting disc brakes can drive you mad and can take minutes and sometimes hours. V‑breaks need very little maintenance. You just need to watch out for pad wear and exchange excessevily used ones, once in a while. For some every few months, for some every few years. Despite what many people say, there is very little difference in braking power between many different v‑brake brands. My properly adjusted no name brakes, on one bike, work nearly identical to much more expensive ones on others. What makes difference is brake pads. Good vs bad ones can make big difference. It is sligly different with caliper brakes on road bikes. Brake pads are still important, but the way different brakes are built results in different braking power and force needed for braking. My Ultegra brakes certainly brake better than my Campagnolo Centaur brakes and need less force to brake. I never had good experience with cantis. They squeel too often. Braking on dry is reasonable but braking on wet is pretty not existing. Disc brakes require proper maintainance which is going to cost you few times more than for v‑breaks and needs to be done on regular basis. Disc brakes also use different oils. Some of them may have decreased performance in very low temperatures which affect some hydraulic oils.

Excessive wear of rims when using rim brakes and tire blowouts are some kind of industry conspiracy. I’ve done thousands of kilometres every year for the past 20 years on flats and mountains and never had such an incident. I have friends who do 20 thousand every year and dozens who do thousands. None of them had to change rims because of exceesive wear and none had tire blowout. I heard of tire blowouts but most of them were related to using carbon rims that heated up on long descends during races. How many cyclist race? Very few. Maybe 1% out of which only some use carbon rims. So it is unimportant issue overall.

There are two additional factors regarding braking worth mentioning. One is proper use of brakes. Many cyclist are not properly educated in that regard and don’t know how to brake. They’re afraid of using front brake and don’t know when and how to use it. They also don’t know that most of braking power comes from front brake. I didn’t know that too. You should never use your front brake when turning. You use it when your wheels are in straight line and before you turn. You should also be very carefull not to lock your rear wheel by using excessive force. Using front brake when turning and locking rear wheel probably account for vast majority of crashes.

The other very important factor is tire pressure. Again, most cyclist don’t know what tire pressure they should use according to type of surface and conditions. If you use max pressure during winter on slush or icy road you will surely crash no matter what kind of brakes you have. You mustn’t believe what is printed on the side of the tire as minimum pressure. There is mostly no such thing as minimum pressure. Maximum pressure shouldn’t be exceeded. But minimum one is up to you. On my recreational 29-er with v‑breaks, for off-road use, I use 2.0 inch tires from spring to autumn. With pressure ranging from 20 PSI to 30 PSI depending on conditions. For winter, when riding on snow and ice, I switch to 2.3 inch tires with pressure around 15 PSI. But I’m heavy. My son, roughly half my weight is using 10 PSI on his MTB bike with 2.0 inch tires during winter. On my trekking and cross bikes, I may use as much as 80 PSI on dry conditions and go down to 30–35 PSI on my 700x38C tires during winter. It is more difficult to drop pressure on a road bike. If you go too low, you risk pinch flats. I normally use 100 PSI in dry conditions. I may go down to 70 PSI on wet but I avoid riding road bike in wet conditions and never ride it in snow or ice. Lower pressure is going to increase your traction. You will go slower but bike will feel more stable nad your crash rate will surely drop.

Thanks for the detailed thoughts here, Jack. I’d just reiterate the warning that running tyres too low can result in pinch flats (a.k.a. snakebites), which goes for mountain bike tyres as well as road tyres.

Agreed. Pinch flats depend to some extent on the strength of the tyre. On my mtb I use schwalbe land cruisers, which are a very sturdy semi-slick. They weigh nearly 1kg each for the 2.0 version. They hardly ever pinch, even at low pressures, and when hammering a rocky descent in the peak district. My Schwalbe Nobby Nicks are a much gripper but lighter tyre. The 2.3 weighs about 650 g. Now this tyre pinches more more easily. I’m 13.5 stone but I need at least 30psi in the back as I like to really go at the descents with those tyres on.

It’s very much a combo of the terrain and speed you are riding at. If you like to hammer rocky descents and are a heavy rider, using a low weight tyre, you will need high pressures. I know this from riding with mtb clubs and seeing who gets the pinch flats over the years. Some people need 30psi or more. Hardtails are worse too as the rear takes a hammering on rocks. 

Of course if you run tubeless you will not get pinch flats.

“Excessive wear of rims when using rim brakes and tire blowouts are some kind of industry conspiracy. I’ve done thousands of kilometres every year for the past 20 years on flats and mountains and never had such an incident. I have friends who do 20 thousand every year and dozens who do thousands. None of them had to change rims because of exceesive wear and none had tire blowout.”

Sorry, but you are wrong. Whilst I have never had a blow-out, to say that nobody ever had to change a rim due to it wearing-out, is nonsense. I commute only 9kms each way, through Copenhagen, and am on my third front rim, due to wear. They last approx 14 months, before wearing through. I use a hub-gear with a coaster brake on the rear, so the front v‑brake gets most of the work (there is a lot of stop-start). The rims are mid-range 700c aluminium jobs and they wear-through.

I also spent 2 years cycling round the world and had both rims wear-out during that trip. I had to true them a few times as well.

Just because you and your friends haven’t had it happen, doesn’t make it an ‘industry conspiracy’ or myth.

I’ve just come across your blog. Great, thank you. I may have missed this in the discussion, but do disk brakes make spoke changing harder? Even hand-built wheels suffer under load and when I have toured, replacing spokes has been one of the commonest “major” repairs needed. (Tandem and solo — but more on tandem). My old tandem has a drum and rim brakes — you need to really anticipate when to brake with that set-up!

Hi David. This is rather subjective, but the simplest answer is that disc brakes don’t make spoke replacement significantly more difficult. The hub flanges are broader which might actually make spoke insertion easier; on the other hand, depending on the spoke in question, it might be necessary to remove the disc rotor, although to do so is usually a simple case of removing some bolts. Certainly with rear drive-side breakages (the most common on tour), there’s every possibility it’ll be exactly the same routine with a disc hub as with a non-disc hub. I’d be interested to hear others’ experiences with this.

Thanks for the article and the discussion. I would guess that for a long distance tourer travelling the globe, rim brakes would be best as if your wheel collapses in a far off land, you are much more likely to get a replacement wheel to fit rim brakes rather than getting one to fit disc brakes

Really it’s only ever the hub that’s disc-specific. You can use any either kind of rim with disc brakes, and the spokes are also the same, if usually shorter for disc hubs. Also many of the hub’s components are interchangeable across models and brands in a pinch. Wheels don’t tend to collapse unless in an accident, especially if well built in the first place, so as long as you maintain the hub appropriately, I’m not sure this is really an argument against disc-only wheels.

Nobody mentions here cantilevers, which many touring bikes include for the only fact they are compatible with drop-bar STI levers, but which include the potential inconveniences of v‑brakes but without its braking power (Btw, I am in love of cantilever brakes in my retro mtb, but I would not pay 1500 EUR for a touring bike in 2015 with those brakes). 

A point I don’t get is those Magura hydraulic rim brakes many touring German bikes include. No doubt they brake great, but they sum up all the inconveniences of both systems when travelling: the difficulty of repairs of hydraulic brakes on the road, and the wearing out of the rims.

Cantis are indeed sub-optimal for heavily loaded tourers in my opinion, even though V‑brake-compatible drop bar levers are available these days. The Magura rim brakes I can kind of understand in Germany, because they’re so widespread there, and they are incredibly reliable and easy to maintain (in terms of brake shoe changing).

No idea, but I wouldn’t use them even if they were available. Keep the mechanisms simple and separated, and breakages and repairs will be that much less of a problem.

I run Avid BB7’son my Disc Trucker, I wouldn’t go back to V‑brakes, the bike is my do everything bike and frequently pulls a 50+ kilo trailer, the best way I can describe the brakes is “boringly reliable” Living in Ireland, where it rains most days, knowing you will have braking no matter how bad the weather is, with little lag, puts your mind at rest. Maintenance has consisted of a tweak of the adjusters on the caliper, 30 seconds work at most. Plus the added advantage of not having the rims and bike covered in brake muck every time it rains.

Elephant in the room: hydraulic or cable?

I’m quite happy with my Magura hydraulic rim brakes and I’d use hydraulic disc brakes too if it was a bike packing off road type of trip on a mountain bike rather than an expedition tourer.

I can see the attraction in cable operated brakes for keeping it simple but I don’t find the braking to be consistent, reliable, powerful enough and IME, they require more routine maintenance. On the other hand, if you snap a hydro pipe, which I’ve done once in 20+ years, replacing it requires you’ve brought spares with you and a refill kit.

Having used all of the above on tours (cable disc, cable rim, hydraulic disc and hydraulic rim), I would agree that all have their uses. My long-haul expedition bike has V‑brakes for simplicity and ease of maintenance and because they just work, but I’d happily take hydraulic discs on a short off-road bikepacking trip where the extra braking control and power would make a real difference.

I’ve never experienced any power or consistency issues with cable discs on a touring bike, though. If they’re good brakes in the first place, properly set up and bedded in, and the pads aren’t contaminated, they should provide plenty reliable braking power for most touring uses.

You talk about “V” brakes and not cantilevers. They are different. V brakes are very “on-off” with little modulation. Where as good canti levers have very good modulation. I have been using canti’s for many years on long distance (over a year) tours and have found them very satisfactory. Notice I only use satisfactory and not great. They and V brakes do suffer from fade on long descents and even with dual compound shoes are not very good in heavy rains like Northwest Thailand in the rainy season. BTW even with the best built of wheels broken or bent wheels do occur and are a problem for rim brakes. 

I am going to try the TRP Hylex brakes on my new Soma Saga for a 5 month or so tour in South Ameriaca

Thanks Bill. I do talk about ‘rim brakes’ as distinct from ‘V brakes’ at various points in this article, and cantis come under the former category. Worth reiterating that V‑brakes are mechanically more forceful for the same pulling torque, all else equal, and therefore more appropriate for a fully loaded touring bike. There’s also plenty of modulation available if you use them skilfully.

My BB7s and Spyres have been practically maintenance free. Just changed pads, and, if I wanted to snug up the bite, adjust them when worn. Dead easy. You can do it at the brake lever, on the brakes, or with the cable bolt on the brake. I usually just let them stay a little mushy til it got noticeable on an alpine pass or such.

Disc brakes also perform better under rain and wet conditions. Plus, they don’t freeze overnight in very cold conditions — the best advantage for me. Really annoying to have V‑brakes freeze and not having any brakes at all. Sure, they have proprietary pads, but have you seen how tiny the pads are? And they last a LOT longer than V‑brake pads.

That depends on the pads. There’s not much in it between slot in V brake pads and disc pads so carrying spares isn’t that onerous. Using slot in pads saves a lot of faffing setting new pads up too.

Also choosing disc pad compounds helps longevity. Often the cheaper disc brakes come with organic compound pads which don’t last long in wet weather, especially off road. Sintered pads last longer at the expense of some low speed braking finesse.

I disagree; I commute 15k miles a year and on V brakes I was changing pads every 5oo miles or so. Switching to disc brakes I now change pads every 5,000 miles or so.

I commute, do touring, do just regular road riding and mountain bike riding and NEVER in over 40 years of riding have I had a rim brake pad last only 500 miles, in fact even the fastest wearing black Shimano pads I have are already at the 8,000 mile mark, while I have Kool Stop Salmon pads that are pushing 12,000 miles without any need to replace yet. The only rim brake pads I’ve seen that don’t last long are the cheap crappy ones found on Walmart bikes, but kids don’t ride far so they generally last long enough for the kid to have outgrown the bike and maybe rode the bike 200 to 400 miles in that time period which by then the pads are indeed shot but so is the bike usually by then.

That’s true but you really want to ride a rim that’s way out of true as little as possible, ideally if you’re doing a long trip away from bike shops you should be able to true your own rims, and rotors get pretty easily knocked mostly by other people when you leave your bike parked up. But yes it is good that braking is entirely unaffected by rim condition.

You missed the other big advantage of disc brakes: the ability to run very bent wheels without loss of braking effort or the rubbing issues associated with rim brakes. Or do touring bikes have strong enough wheels that they don’t bend?

This is true, but I’m not convinced it’s a real argument in the case of touring on strong wheels that shouldn’t get bent in the first place (and can be trued if they do). Downhill mountain biking, on the other hand…

(Also, disc rotors get bent too and are much more difficult to true than wheel rims!)

Disc brakes can be trued pretty effectively by eye and using a small adjustable spanner. Surprisingly easy.

You have not addressed the issue of braking loads having to be carried by the spokes when disc brakes are employed; with V brakes the load is taken straight to the forks — any thoughts?

I wouldn’t call this an issue until we hear regular stories of people snapping spokes on their touring bikes while braking with disc brakes. It does depend on wheels being laced correctly, but any decent wheelbuilder would do that anyway.

The rotational load applied to a disc brake is roughly equivalent to the load on a rear wheel under heavy acceleration — a properly-laced 3‑cross front wheel with double-butted spokes should do the job admirably. The real disadvantage I see with disc brakes is that discs are prone to bending under lateral loads, and are completely exposed to mud and grit. And, once your disc is contaminated or bent, it’s going to make horrible screechy noises until you replace both the pads and the brakes. 

And good luck replacing hydraulic hose or locating specfic DOT/mineral oil formulas in Mongolia — or even Northen BC.

Also, DOT fluid freezes at ‑50*C and Shimano mineral oil at ‑35* ish. I mean, most people don’t cycle in those temperatures, but I had to give up on hydraulic brakes on my winter bike after I burst 3 hoses, even after switching to Hayes from Shimano.

I’ve been mountain biking for years in the muddy UK forests and gritty peak district Starting on V brakes and going to disc. Discs are MUCH better and more reliable in muddy gritty conditions. They wear less, make less noise and work better in these conditions.

Discs are also safer in the wet, with little noticeable decrease in stopping performance. 

The latest Disc brakes (e.g. Shimano Deore) and cheap, very powerful and have great modulation. 

A small amount of silicone grease on the pistons every now and again is really all they need. Bleeding is not that difficult to do either. 

I can still understand people doing a world tour on roads wanting rim brakes though.

Which gives a larger penalty in terms of rotational weight on your tires: the need for a certain kind of rim on your tires if you have caliper brakes, or the adjustment in spokes or other specs if you have disk brakes? 

I was told disc brakes can add upwards of a pound in weight to your bike, but was also told the rims needed for calipers affect rotational weight and that rotational weight most affects your speed. However–and bear with me I’m not very knowledgeable here–I seem to be reading something about heavier or stronger spokes being needed with disc brakes?

I’m a fair weather rider on fairly level concrete trails and am looking for speed /weight advantage. Don’t need impeccable braking power.

Makes sense that the force would be about the same as propelling. Though if you break with both hands simultaneously, it would be a bit less, since you only pedal one wheel.

I went to disks after losing so many rims to rim brakes. Mechanical disks are hella easier to deal with compared to oil. Avid BB7s stopped me nicely for many years, then I went to Spyres for their double sided action — better. Barely had to touch the brakes for many years.

@Dana: I agree with most of the things you say, except with your statement that “The rotational load applied to a disc brake is roughly equivalent to the load on a rear wheel under heavy acceleration”
Heavy breaking implies large forces. I believe that if you could apply to the rear wheel the force that would lead to a rotational load that would generate an acceleration similar to that of hard breaking, the bike would not just do a wheelie, but flip backwards violently.

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