At first I used the wrong type of spring. If you use the right spring the brake arm is pulled away from the wheel. The spring are pretty strong, making sure you get a lot of tension on the arms.
Installing these brake arms is kind of a nuisance. There are a lot of moving parts and getting them installed evenly on both sides is more difficult than I though initially. The position of the brake arms between the front and rear brakes different on the same bike.
The brake pads are removed further from the rim in the rear so this makes sense. At least make sure the brake arms on the same side are symmetric. Even this was more difficult than I thought it would be. My steel frame is misaligned in the rear causing the rim to ever so slightly move in the center of the stays.
Next up were the brake cables. I bought Jagwire Universal Sport brake cables in carbon silver, since these most resembled the original color of the cable housing. The kit comes with two cables and a long enough piece of housing for an entire bike. As well as end caps , cable donuts , rotating hooks for cable management, and tube tops for frame protection.
I test this by rotating the handlebars to see if they can move freely. To cut brake cable housing to the correct length you should use a cable cutter. Using a hacksaw takes a more time and the result is a sloppy frayed end. This would mean that when tension will be placed on the brake cable the cable housing would fit into the barrel at an angle. This is usually on the left side of the front brake, the right side of the rear. In the early '90's, this adjustment required a 2mm Allen wrench , but newer models use a Phillips screwdriver.
Dia Compe style cantilevers often use a totally different approach. The Dia Compe system doesn't use the spring hole in the cantilever boss, but has a separate spring block as part of the cantilever assembly. This spring block is the first part to go onto the boss, and it has a hole for the end of the spring.
When the bolt holding the cantilever to the boss is loose, the spring block can turn freely, but when this bolt is tightened, it locks the spring block in place. The spring block has flats for a cone wrench usually 13 mm to let you rotate it to provide the desired tension. Note: Brakes which use the adjustable spring block do not use the cantilever boss as a bearing surface; instead, they have a hollow cylindrical bushing sleeve which fits over the boss.
Unlike most other types of brakes, cantilevers permit different setups which provide more or less mechanical advantage. Mechanical advantage is a key concept, which you must understand before you will be able to fine-tune your cantilever brakes.
Mechanical advantage is commonly referred to as "power", when discussing brakes, and it is common for people to confuse this with quality. A brake may be designed for any amount of mechanical advantage, but there is a fairly narrow range that is useable. People with brake problems often think that they need more "power," when they actually need less! In particular, when modern low-profile cantilever brakes are used with drop-bar type brake levers, the combination produces excessive mechanical advantage.
This problem also arises when using direct-pull cantilevers such as Shimano's "V-Brakes" with levers made for conventional center-pull cantilevers. If you have too little mechanical advantage, when you squeeze your brake handles, you will feel a nice firm response. In fact, if you just squeeze the brakes of a bike that is not moving, your first impression may be that the brakes are in great shape, because they feel so solid and firm If you have too much mechanical advantage the lever will be all-too-easy to pull, but it will run out of travel and bump up against the handlebar before the brake is fully applied.
Once the lever hits the handlebar, it doesn't matter how much harder you squeeze! If you try to correct this by tightening up the cable, you will wind up with the brake shoes too close to the rim when at rest, which will cause them to rub, especially if the wheel isn't perfectly true. Excessive mechanical advantage can often be reduced by raising the cable yoke and lengthening the transverse cable, so that it makes a sharper angle around the yoke.
Unfortunately, there isn't always room to raise the yoke far enough, especially in the rear of smaller frames. Mechanical advantage can vary as the brake is squeezed. Tweet Follow sheldonbrowncom. Experiment with how much to thread the barrel adjuster back in until the brake lever actuation is to your liking. Lastly, it is good to apply a bit of triflow to the spring and pivot point on the brake arm so that actuation is smooth.
It is a bit of preventative maintenance that will keep your brakes working great throughout the season. As your brake pads wear down, you can extend the barrel adjuster unthread to regain the correct clearance as the initial setup. Lubrication points shown in the example below. As always, I welcome any other tips you may have from your own setups and hope that my experience will help save time and frustration.
I have seen plenty of cantilever setups and this method seems to work the best to get the most out of your brakes. Thanks for reading! You are commenting using your WordPress. You are commenting using your Google account.
You are commenting using your Twitter account. You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email. Skip to content Today I am going to share my best method for setting up a cantilever brake. Here is an example of a fairly standard TRP cantilever brake.
Straddle wire angle makes a big difference. A cantilever brake is a rim brake where each brake arm has the brake shoe and the cable attachment both on the same side of the support the pivot.
So that the cable can come from above the tire, the pivot must be below the brake shoe, attached to the frame. There are also differences between braking on a mountain bike, a tandem bike, and a road bike. The short answer to the braking dilemma is that disc brakes or v-brakes are great for mountain bikes and cantilevers are generally preferable for tandem and road bikes. These cyclocross cantilever brakes are well known and have been tested to the extreme for years.
Rim brakes are more aerodynamic than disc brakes. Rim brakes are easier to repair. Linear-pull or v-brakes are an evolved version of cantilever brakes that provide more power through increased leverage. V-brakes are a popular style of brake. They are still cable-actuated but far easier to adjust than traditional cantilever brakes. Pads are also much easier to replace than those on cantilever brakes.
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