Let’s talk about V-brakes and Cantis

Hello, friends 

Today, I will talk about V-brakes and cantilever brakes – the two most popular rim brakes found on cyclocross, entry-level MTBs, touring, and commuting bicycles.

Let’s start with the similarities between the two. On top of my head, I can list the following:

  • Both models are mounted to the fork’s legs and the seat stays of the frame and are triggered via a cable connected to a brake lever.
  • Both models use identical mounting bosses.
  • Both models offer a decent amount of tire clearance. (Cantis win in that regard though.)

However, there are MAJOR dissimilarities between the two that every cycling guru must be aware of. 

The main one is the cable pull. Even though both models are cable-operated, the lever designed for each of them pulls a different amount of cable. For that reason, you can’t use a V-brake lever on a cantilever brake or vice versa. If you ignore this rule…bad things will happen.

The other important dissimilarity would be the brake pads. You can’t mix and match them as they’re brake-specific.

Mounting Bosses

The frame in the image was originally designed for cantilever brakes.

I can tell because I own a similar frame, and you can also see the cable stopper in the middle between the rack/fender eyelets.

The bosses, also known as braze-ons, can work with V-brakes as well.

However, there is one exception to this rule – older touring bikes produced around the mid-80s. These bikes have narrower bosses made for cantilever brakes with small tire clearance. It’s unlikely that you have a similar frame, though.

Cable Pull

99% of cantilever brakes and V-brakes are cable-actuated. Hydraulic rim brakes exist, but they are a rarity, and there’s little demand for them.

The mechanism of cantilever brakes and V-brakes is similar.

The brake lever pulls a brake cable which in return intiates a small rotation of the brake arms. The brake pads on the arms rub against the rim and slow down the wheel.

When the lever is released, a set of springs return the brake arms to their original position and free the wheel.

But, as I already said, there’s an important difference – the amount of pulled cable is different for each setup.

Why? 

Due to the dissimilar mechanical advantage/leverage of the brakes.

By default, V-brakes have a higher mechanical advantage than cantis. 

In the case of V-brakes, the cable pulls the brake arms from a more advantageous position and thus the user has more leverage over the brakes.

Cantis, on the other hand, have a transverse cable allowing the user to adjust the mechanical advantage. But regardless of the position, the leverage is almost always smaller than what we observe on V-brakes.

The graphs below will make everything clear:

The architecture of V-brakes removes the transverse cable found on cantilever brakes. Consequently, the brake cable can directly exert a ton of force on the brake arms.

Furthermore, V-brakes operate with a longer rigid effort arm. This peculiarity boosts the leverage even more.

The graph above illustrates the effort/pull of cantilever brakes. Notice the pulling angle, the soft connection and the shorter brake arms.


I know that I still haven’t explained why the dissimilar leverage requires a different cable pull and I am about to make just that.

First, we have to talk a bit about the term mechanical advantage.

Mechanical advantage is a measure describing how much a tool amplifies one’s input force.

The classic example would be a pry bar.

The longer and thicker the pry bar, the greater the mechanical advantage and the amplification of one’s force.

To find out the mechanical advantage of a tool, one has to divide the output force by the input force.

For instance, if the output force is 6N whereas the input force is 3N, the mechanical advantage would be 6/3=2.

The leverage of a tool can also be measured by dividing the input displacement by the output displacement.

The input displacement = how much you move the end of the tool that you’re holding.

The output displacement = the travel of the other end of the tool

When the output distance is bigger than the input distance, the mechanical advantage is poor.

The “B” side of the lever below has a poor mechanical advantage because it’s shorter. When you apply force, it moves less than the “A” side.

Low Mechanical Advantage

Or in other words, the input distance is smaller than the output displacement.


If we flip the script, we observe the opposite:

High Mechanical Advantage

In this case, a larger input generates a smaller displacement/output.

And I want to stress this again because it may sound a little counterintuitive.

Many people may conclude that more leverage results in smaller input because of the extra advantage, but this isn’t the case. The additional leverage reduces the effort needed to exert force onto an object but increases the input displacement.


So, what does this mean in the case of V-brakes and Cantis?

It means that V-brakes need brake levers that pull MORE cable whereas cantilevers need brake levers that pull LESS cable.

Why?

Because the brake lever of a V-brake has to move MORE to trigger the same output displacement (movement of the brake arms).

If we put a canti lever on a V-brake, it simply won’t move enough cable for proper braking.

And if we put a V-brake lever on a canti brake, it will move too much cable and cause the brake’s jaws to close too fast (poor modulation/control over the braking force).

For that reason, V-brakes are called LONG pull brakes whereas cantilevers are known as Short Pull.

Different Brake Pads

By default V-brakes and cantis use completely different brake pads even though the braking mechanisms are similar.

The canti pads come without a mounting system and are instead secured by bolts threaded into the brake arms.

Cantiliver brake pads

Meanwhile, V-brake pads come with their own attachment hardware.

V-brake pads

Note: Some rare modern cantilever models can technically accept V-brake pads. But those are a rarity, at least where I live and have never seen them.

Conversions

I would also like to discuss the idea of switching from one type of brake to the other.

Option 1: Cantilever to V-brakes

This is the most common pathway as V-brakes are a newer technology (even though they’re pretty old at this point).

So, if you want variety and availability, V-brakes are a clear winner.

The switch to V-brakes is easy. You will need new a cable and housing, of course.

And the main problem that you will face is cable routing.

You can’t use the final cable stops because they’re designed for cantilever brakes and pull from the center.

A V-brake cable cannot be routed through the hanger above as it’s designed to pull from the side.

So, there are two options here:

  1. Use the original cable routing of the cantilever up to the final cable hanger and then bypass it.
  2. Use zip ties to mount the housing to the frame and completely ignore the original routing.
  3. Buy separate cable stoppers and mount them to the frame.

Option 2: V-brakes to Cantilevers

This is a less common scenario, but technically not unheard of. The main issue is once again the cable routing.

If the frame is originally designed for V-brakes, you will need a bolt-on cable hanger for the seat stays and the fork.

Tektro Fork-mounted Cable Hanger

The hanger above is attached to the fork (there’s a hole in the middle usually).

Notice the hanger in the middle of the fork. (This is a custom model and just for illustrative purposes.)

In the past, the front cable stopper/hanger was mounted on the fork steerer via an adapter. (image below).

I’d stay away from this converter, although it technically works.

This style causes a lot of fork shuddering (vibrating of the fork) during braking, and people began switching to cable hangers that attach to the eyelet in the middle of the fork.

For the rear, the only option is an adaptor mounted to the seat post or the binder bolt.

This is a rear cable hanger made by Origin8. It attaches to the seat post collar.

Why convert?

The advantages of converting to V-brakes are fairly obvious but still deserve a mention:

  • More brake options
  • More stopping power with fewer adjustments (Cantis can kinda match the power of V-brakes but require a lot of tinkering)
  • No annoying cables in the middle of the frame and fork
  • Cheaper (high-end cantis are a rare product and cost more)
  • Brake levers are easier to find
  • Compatible with a greater number of suspension forks

The pros of switching from V-brakes to Cantilevers are less obvious but real, though:

  • Compatibility with drop bar levers (canti levers are short pull and therefore compatible with brake levers designed for drop bars – one of the reasons why you see cantis on cyclocross bikes)
  • Extra clearance. V-brakes offer decent tire clearance but not as much as cantilevers.
  • Lower mud accumulation
  • Lighter (potentially – it doesn’t matter, though)

TL:DR;

I know that this post has a ton of info packed into it. So, I’d like to end it with a TL:DR; so that all the rookies out there get maximum value.

  • Cantilever and V-brakes operate similarly and use the same mounting points known as braze-ons or brake bosses.
  • Theoretically, cantilevers can offer the same braking power as V-brakes but to get there, you will have to perform a lot of tinkering.
  • It’s fundamental to remember that V-brakes and cantis use levers with different cable pulls. V-brakes are long pull, cantis are short pull. You can’t mix levers.
  • V-brakes are NOT compatible with drop bar levers (unless the model is super custom) whereas as Cantilivers are.
  • Cantilivers are somewhat exotic. V-brakes are ultra-common.
  • Cantis offer a lot of wheel clearance.

What would I choose?

I prefer V-brakes for their simplicity and the only time when I’d choose cantilevers is when I want to run drop bars in conjunction with wider tires.

I hope this was helpful, my friends.

Until next time

– Rookie


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