SORTE D 7stoppers
Pro-tips to keeping your in perfect nick Of all the parts on your bike, the brakes should demand the most attention. Here’s how to give them some loving…
1Check the pads
Brake pads are easy to inspect. On calipers with pistons either side of the disc, pins hold the pads in. They’re either threaded in, or retained with R-pins – anti-rattle plates usually need removing too. Some can be removed with calipers in situ, some will need the whole assembly removing for access. Replace if they’re less than 2mm thick, or show any sort of damage to the friction material. Some swear by greasing the back of pads to prevent squealing – but wellmaintained calipers with all anti-rattle plates shouldn’t need it. It only serves to contaminate, and attract dirt.
2Avoid disc dramas
Brake discs have a minimum thickness stamped on them. It’s an easy measurement with a set of vernier gauges. If they’re too thin, replace. Examine the rotor surfaces for cracks. If they’re floating, examine the floating bobbins. Look for missing clips or washers, and excessive play. If you have experienced pulsing at the lever, also look for discrepancy in bobbin movement. Failing that, raise the front wheel from the floor and spin the wheel. Hold a pencil against the fork leg with the tip against the disc surface – if the disc pushes the pencil back by large amounts, you have a warped disc.
Remove calipers one at a time, and gently pump the lever to ease the pistons out slightly. An old toothbrush and soapy water is enough for normal brake dust. Brake cleaner can dry brake seals – only use as necessary. Once the caliper and pistons are clean, apply silicone grease very sparingly to the pistons and push them back.
There are many ways to bleed a brake: vacuum pumps, syringes, one-way valves, or just a simple tube and a jar of brake fluid. Whichever you choose, ensure the tube fits the bleed nipple securely, and only open the nipple as much as is required for fluid to flow. Use a new bottle of quality brake fluid – not cheap stuff from the local auto factor.
6Don’t forget the master cylinder
Any leaks or split seals require attention, and if you’ve tried everything else, replacing the piston and seals often cures brake issues. It’s simple – you just need circlip pliers to remove the piston retainer. Clean around the external parts, and apply a small amount of grease on the pivot and where the lever actuates on the piston.
4Sliding bracket care
Single and two-piston sliding brakes require the sliding elements to be maintained. Remove the sliding bracket, and clean off light corrosion with a brass wire brush. Replace any split or hardened rubber seals, and use a rubber-friendly grease to lubricate inside the sealed portions. Badly corroded pins should be replaced.