Question: Do you have any tips on installing and setting up Shimano Dura Ace 9000 brakes? From: Phillip
Some things to keep in mind are that the max tire width recommended by Shimano for these brakes is 25mm. The max rim width compatible with these brakes is 28 millimeters. If you are using 24-28mm rims you’ll need the R55C4-1 brake pads which are thinner and made for a carbon braking surface. Unfortunately, Shimano doesn’t make a brake pad for alloy rims that measure between 24 and 28 millimeters.
Before you start the installation, set the centering bolt so that the upper edge of the bolt head sits down below the surface of the brake arm. When you have it in the right spot, the roller arm on top of the brake will sit flush with the rest of the brake caliper.
When installing the brake on the bike you need to make sure that you have enough thread engagement between the brake fixing nut and the brake anchor post. You should have at least 6 turns of thread engagement with the included washer installed between the caliper and frame or fork. If you don’t have enough thread engagement, you’ll need a longer nut. If the nut bottoms out on the post before the brake gets tightened down to the frame or fork, you’ll need a shorter brake fixing nut.
When torqueing down the brake fixing nut, pinch the caliper down so that the pads touch the rim. This will help to center the brake. Use a torque wrench to torque the nut to 8-10nm.
Before you anchor your cable, close the quick release lever at the clamp. Be sure to loosen the cable clamp bolt at least a few turns so when you pull the cable through, the clamp won’t damage the low friction coating on the cable. Pinch the pads down against the rim and then torque the cable anchor bolt down to 6-8nm.
Now we’ll do initial brake pad setup. Pull the brake lever and hold it while you loosen one of the pads. Center the pad on the rim while gently pulling on the brake lever and then pull the brake lever tight to hold the pad in place while you tighten it down. Repeat the process on the other brake pad. Now use the barrel adjuster and brake centering bolt to achieve a 1.5-2mm gap between the rim and the pad on each side.
Now we’re ready to toe in the pads. I have a nice little trick for doing this that we covered in an earlier video, but I’ll show it again here. Take a couple of business cards folded in half and place them between the last 15mm of the trailing edge of the brake pad and the rim. Pull the brake lever to hold them in place. Loosen one pad and then tighten it back down again. Repeat this process on the other side and remove the business cards. Check your work to make sure that the pads are still lined up with the rim and that the pads are contacting the rim evenly with the leading edge of the pad contacting the rim first.
Check your pad clearance, centering, and feel again. Then give the brake lever a couple of hard pulls to make sure the cable and housing are fully seated and to ensure that the cable will stay clamped under heavy braking and you are done.
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