In this article I’m going to explain how to restore and install vintage Shimano cantilever brakes found on my Koga Miyata Adventure from 1986. Although they have seen better times these Shimano Exage Trail BR-AT50 brakes in combination with the first gen Shimano Deore XT BL-M700 brake levers are simply put a gorgeous piece of retro cycling tech.
And it’s up to me to restore them to their former glory and unleash some 80’s stopping power on the world!
Let’s get started.
Step 1 Removing, disassembling and storing cantilever brake parts
Obviously the brakes first need to be removed before any restoration and re-installation can take place.
A tip when disassembling anything is to make photos when stuff is still in place, so you know what goes where during the reassembling phase.
I also keep small plastic containers ready so as not to loose any tiny screws, bolt, and what else. The brake arms alone consisted of about 60 pieces. The majority of these parts are very unique to the set, and you don’t want to loose a single item.
Step 2 Cleaning cantilever brake parts
After I’ve removed all parts I clean them using mineral spirits. I reuse the mineral spirits and store the dirty sludge in a spare container.
Some parts, especially screws, will need some rust removal. Don’t try to remove aluminium oxide with rust remover. The aluminium will get a dull white look to it and it the rust remover eats away at the aluminium.
Step 3 Polishing brake arms
Since the brake arms are made from aluminium, they can be easily polished. For more information about how to polish aluminium please follow the link.
Step 4 Reassembling vintage Shimano cantilever brakes
After I’ve cleaned and polished each part (I also polish nuts and bolts), it’s time to reassemble each individual brake arm. Ik put grease on threads to prevent them from seizing in the future.
The previous owner had installed the wrong type of brake pads (with the bolts), so I bought a couple of pairs of nice two-piece cantilever brake pads.
Step 5 Installing vintage Shimano cantilever brakes
When I’ve assembled the brakes it’s time to install them. The brakes come equipped with springs. There are springs for the left and springs for the right side of your bike. At first I used the wrong type of spring. You’ll immediately know this since there’s no tension on the brake arm, so it just hangs there loosely.
Step 5. 1 Using the right 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. If you look at the front of your bike, you’ll need a spring rotating clockwise for the left-hand side and counterclockwise for the right-hand side.
Step 5. 2 Mounting the brake 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.
Step 5. 3 Checking for symmetry
I looked at pictures online to see what the right position of the brake pads should be, but the results we’re inconclusive and probably dependant on the combination of fork and rims. 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.
Step 6 Installing brake cables
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.
Step 6.1 Measuring cable housing length
First off you need to measure the length of the cable housing you’re going to use. I use the original catalogue as reference but make sure the cables aren’t going to be too tight. I test this by rotating the handlebars to see if they can move freely.
Step 6.2 Cutting brake cable housing
To cut brake cable housing to the correct length you should use a cable cutter. Since I don’t have one I used a small hacksaw. Using a hacksaw takes a more time and the result is a sloppy frayed end.
Since the cut is so raw, I needed to use a tooth pick because otherwise the cable wouldn’t fit anymore.
There are alternatives to cutting a cable housing with a cable cutter, like using a dremmel (I don’t have one of those either).
Anyway, I’ll definitely consider using something else next time. It worked, but there’s room for improvement.
Step 6.3 Making custom cable housing end cap adapters
As it turned out the end caps for the cable housing we’re too thin for the barrel adjuster of the brake levers. 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 both ugly and ill-advised. I have no idea what the original setup looked like without the play.
So I decided to make adapters to fill up the gap between the end gaps and the barrel adjuster.
Luckily I found an arbitrary piece of plastic which I cut to the correct length. It fit snugly around the end caps, but was still a bit too big for the adjuster.
I sanded it to the right size and with a permanent marker turned the dull grey into black, making sure it would blend in with the cable.
Step 6.4 Cutting the brake cable
Since I don’t have a cable cutter I use side cutting pliers on a taped cable to prevent them from fraying and cut them to the correct length. This works amazingly well.
Step 6.5 Installing the cable
For more information about how to install the correct brake cable into your brake lever read my article “How to reaplace a cantilever brake cable“.
Step 7 Adjusting and finetuning your vintage Shimano cantilever brakes
Unlike other brakes that use a single brake cable, these old-style cantilever brakes need another cable that is stretched over a center cable yoke.
This cable has a very distinct cable stop on one end. I cut off the other end. Since I don’t have a cable stretcher I bend the cable sideways and then keep it in place with pliers so my other hand is free to tension the screw.
The part that comes out of the cable housing goes straight down. The cable yoke screw has a little hole in it to facilitate this proces.
Finetuning your brakes by moving the pads, cables and barrel adjuster can be a long process, which is difficult to explain. But when you’re happy with your setup a final cable cut rounds up the project.
And that’s how you install vintage Shimano cantilever brakes!