A Must-Know Peculiarity of Road Levers

from Rookie’s keyboard

Hello, friends

Today, I am going to reveal a peculiarity of road levers that every road cyclist has to know. 

Regular road levers are engineered for short-pull brakes and should not be combined with V-brakes.

Short and Long Pull Brakes

Mechanical/cable brakes divide into short and long pull depending on the cable’s travel.

The dissimilar cable pulls are the result of the brakes’ different leverage/mechanical advantages.

When it comes to cable brakes, the term mechanical advantage describes how hard the brake arms grab the rim per unit of effort.

Out of all rim brakes, V-brakes offer the greatest mechanical leverage because the cable is pulling from the most advantageous angle.

The greater mechanical advantage of V-brakes requires longer travel of the brake lever.

This may seem a little confusing because the brain naturally associates higher mechanical advantage with less effort and shorter travel. Only the effort part is true.

The mechanical advantage of a tool can be measured by dividing the input displacement by the output displacement.

The greater the input displacement in comparison to the output distance, the larger the mechanical advantage.

Let’s observe the operation of a simple lever.

In the image above, the B side of the lever is longer and subsequently has a greater mechanical advantage.

The longer arm has a longer travel than the shorter one.

In the world of V-brakes, this means that the levers move a bit more per 1mm of brake arm movement in comparison to brakes with a smaller mechanical advantage.

This creates a possibility for the lever to touch the handlebars before the brake arms have moved sufficiently to grab the rim and the wheel.

To prevent this, V-brake levers are designed to pull more cable.

On the contrary, other rim brakes (calipers, cantilevers, and mini V-brakes) offer a lower mechanical advantage.

Their “input displacement” is smaller and subsequently, the levers don’t have to pull as much cable to trigger the brake.

If you combine short-pull brakes with long-pull levers, the brakes would lock the rim before the levers have reached the end of their travel. 

Option 1: Switch to V-brake Road Levers

One of the possibilities is to get a set of road levers designed to work with V-brakes from the get-go.

The table below contains a list of models plus their weight:

ModelWeight
Tektro RL520 V320g
Cane Creek V310g
Dia Compe 287V Aero302g

The con of this method is that V-brake road levers do not offer a dual control function. In other words, you will need a separate shifting system.

The three most common options are:

a. Downtube shifters

b. Bar-end shifters

c. Stem shifters

Option 2: Adapters

You can also use a cable adapter that increases the amount of cable pulled by the lever. The increased cable pull allows the combination of road levers (short pull) with V-brakes (long pull).

One of the most popular models is called Travel Agent and is made by Problem Solvers. It replaces the V-brake’s noodle and doubles the cable pull via a system of small pulleys.

The main advantage of this solution is that you can keep your existing road levers.

Also, this is the only way to combine STI with V-brakes.

The downfall of adapters is that they don’t look clean and can be a bit difficult to set up.

Alternative Routes

Option 1: Mini V-brakes

Mini V-brakes are V-brakes with shorter arms offering similar braking power.

The shorter arms reduce the mechanical advantage and make mini V-brakes compatible with short-pull levers.

Mini Vs have some notable downsides, namely:

  • Poor tire and mud clearance
  • Complicated fender installation
  • Very low tolerance of non-true rims

Option 2: Cantilever Brakes

Cantilever brakes are also short-pull and are therefore compatible with road levers. Cantis are a bit more difficult to tune but once adjusted properly they offer adequate braking power. The main advantage of cantis is the insane tire clearance.

Option 3: Stick with calipers(recommended)

As always, the default option (caliper brakes in this case) is the best one (unless you need ultra-wide tires). 

Road bikes favor simple, lightweight aero design. Caliper brakes fit the bill because they require a hole and a bolt to mount them. 

Тhey save weight and keep the design slick in comparison to V-brakes which demand two separate bosses.

The absence of separate brake bosses in the case of caliper brakes simplifies fork and frame production.

Also, the mounting system of caliper brakes prevents the fork and frame from flexing when braking.

V-brakes, on the other hand, “encourage” flex which is the reason for the existence of V-brake reinforcers/boosters.


Until next time,

– Rookie


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