Brakes.

Drop handlebars are generally not suited to V-brakes (left picture below). The "travel" in the brake levers does not match the cable travel required by the brake callipers. Some adaptors exist so that drop-bar brake levers can be used with V-brake arches (callipers) but reviews are generally not positive. There are a few drop-bar V-brake compatible levers coming onto the market but not yet in 9-speed STI levers. So, there are compatibility issues steering us away from V-brakes, at least on drop-bar models. But V-brakes are light and easy to adjust so it is not a black and white issue. Some people claim heat dissapation is better on cantilevers. Also that clearance from mudguards is better with cantilevers over v-brakes.

Side-pull callipers are normal on racing bikes with drop bars but they are not suited to touring bikes. The bigger profile tyres such as 35C, with mudguards, put the mounting point for side-pull callipers so far away from the rims that the callipers would be too weak. So, when rim brakes plus drop handlebars are combined, we use cantilever brakes (right picture).  These have been standard on most touring bikes for several decades.

But there is a problem with either V-brakes or cantilever brakes. They  wear out rims, especially on front wheels where most braking force is applied.  Friction is high. Abrasive matter gets picked up and embedded in the brake blocks. This is at its worst in wet conditions. Occasional filing of the brake blocks to remove flakes of anodizing can reduce this wear. But the wearing is still significant. It is a real problem for bikes on long trips. The fact that many modern rims have a wear indicator line does nothing to solve the problem.

After a rim is worn, you eventually find, when pumping up the tyre, that the rim folds out from the added pressure. You need a new rim when that happens and if you are in a remote place that will probably be difficult, or impossible, to find in your diameter and spoke hole number. So you wait whilst one is flown in. Then you need to build the wheel or find someone who can. You need the old spokes to be compatible.

The other problem is that rim brakes depend on rims being straight. You end up having to tune your spokes in order to stop brakes from rubbing.  If a spoke breaks or if you otherwise damage a rim, and you have rim brakes, the brakes immediately don’t work properly. For decades we had to put up with this. But, when disc brakes were developed for mountain bikes, we figured we had to try them out on touring bikes.

When we first tested a front disc brake we immediately noticed it was stronger. That was with Shimano cable discs using "metal" pads. Coming into corners, the   

Close-up of a rear rim that has done 14,000km, pumped to 80 psi. It is starting to bow out. Soon it will crack, either when a pothole is hit or when the tyre is being inflated.

Disc brakes apply greater twisting forces on hubs, spokes, nipples and rims. But, as these are long distance touring bikes none of those components are on the “lightweight margin” and are quite compatible with the disc system. Further, we are using a gauge of fork blade and a fork dropout which prevent the movement of the hub under heavy braking. It is essential that front hub quick release skewers be kept tight. It is also essential that the rotor ringlock be kept tight. There is a special tool (same as the cassette lockring tool)  and you should carry one on a long trip. You can tell if the rotor is loose by holding the front brake lever on hard and rocking the bike back and forth, feeling at the junction of the rotor and the hub for any movement. There should be none. Do not do this when the rotor is hot.

Shimano tool for removing or tightening the disc rotor lockring. (Also for the cassette lockring.)

Stainless steel disc rotors do wear out. But nothing like at the rate that aluminium rims wear. And, if the disc pads are always replaced before the pads wear down to metal, a rotor will last for years. When you wear the pads right down and reach that metal-on-metal stage you change the pads immediately. That means you should have spares with you when travelling. Use BR-M965 metallic pads as fitted on the new bikes. Pads last about 5,000km on the front of a touring bike used in the city and on tours.

Disc rotors also can be bent, particularly during transportation. But it is not hard to avoid this. It is best to pack the front wheel with the rotor away from the frame to stop it being pushed against the frame. Have the wheel securely tied (tight zip ties) to the frame. See our packing advice.

If disc brakes are so good why not have them on the rear too?

The majority of braking occurs at the front and the rim-wear problem from side-action or rim brakes is far bigger on the front. So a front disc brake on a touring bike achieves a lot by itself. With a 70gm heavier rim on the rear wheel, doubling as a heavier load-bearing rim, the rear wear aspect is substantially addressed.  

We prefer to use cr-mo as a frame material. And we prefer the classic straight tubing lines. This does not sit well with the normal way designers have integrated rear disc brakes onto touring bikes. They normally use aluminium tubing for their frame material and forged ends also in aluminium. It all looks a bit "busy" back there.

There is something appealing about having two different brake systems on a bike that is supposed to be able to be ridden around the world. Brakes are incredibly important on a bike. We happen to have front brake pivots on the forks to mount the front light bracket. 

The light bracket will still mount on the pivots if they are in use for brakes. The rear brakes will fit on these front pivots. We supply, with every bike, the small component needed to be installed in the headset that would allow the rear brakes to be moved to the front. (Front cantilever hanger). So, if you are in Outer Mongolia and wear out your disc pads, and lose your spares, by virtue of having two brake systems, you move the back to the front and carry on. You have no rear brakes but will still manage.

Hydraulic disc brakes.

Whilst hydraulic disc brakes have an excellent feel there is a concern about servicing them in remote places . This is a reason why we have not used them. We are not committed forever on this point. STI levers, rear derailleurs, cartridge bottom brackets and more, also can’t be easily serviced in remote places. Yet we use them and World Randonneurs have been travelling the globe for decades. We are simply watching technology bring us more options. In the meantime, Shimano mechanical front disc brakes are very reliable and we are happy to fit them for front wheels on all models.