Change your brake fluid & bleed the brakes?

Steps

1. 1
   1

   Get the right fluid & protect the paint

   Use the exact DOT rating stamped on the reservoir cap (commonly DOT 4) from a sealed bottle - opened fluid has already absorbed moisture. Do not substitute DOT 5 (silicone) unless your bike specifically calls for it; it is not compatible with normal DOT 3/4/5.1 systems. Fluid strips paint, so cover the tank and bodywork.

   Warning

   Danger
2. 2
   2

   Open the reservoir & rig the bleed tube

   Set the bars so the master-cylinder reservoir is level, then open the cap and diaphragm. Top the reservoir up. Fit a clear tube snugly over the caliper bleed nipple and run it into a catch bottle with a little fluid in the bottom so air can't siphon back.

3. 3
   3

   Bleed: pump, hold, crack, close, release

   The cycle: pump the lever a few times and hold it in; crack the bleed nipple open a fraction (fluid and air push out down the tube); close the nipple; then release the lever. Repeat. Watch old dark fluid give way to clean, and bubbles disappear. On twin-disc brakes, do the caliper farthest from the master cylinder first.

   Danger
4. 4
   4

   Finish, torque & top up

   Once the fluid runs clean and bubble-free with a firm lever, hold light lever pressure and nip the bleed nipple to its torque spec on the last close so it seals without over-tightening. Top the reservoir to the upper line, refit the diaphragm and cap, and wipe every trace of fluid off with brake cleaner.

5. 5
   5

   Test firm before you ride

   Pump the lever - it must come up firm and stay firm. Check for leaks at the nipple and unions. Then test the brakes at walking pace before any real ride. Take the old fluid to a proper disposal point; don't pour it away.

   Danger

Fits these bikes

All motorcycles