Removal
Warning: Before starting work, ensure the motorcycle is stabilised and adequately supported. This will help prevent it from falling and causing injury to the operator or damage to the motorcycle.
1. Remove the rider's seat (see page 16-13).
2. Disconnect the battery, negative (black) lead first.
Caution: To prevent paint damage, do not spill brake fluid onto any area of the bodywork. Spilled brake fluid will damage paintwork.
3. To drain the fluid from the master cylinder, attach a tube to the right hand caliper bleed nipple, slacken the nipple and allow the fluid to drain into a suitable container. Operate the brake lever until all fluid has been expelled.
4. Note the setting of the brake lever adjuster to ensure it is returned to the same position when the overhaul operation is complete.
5. Remove the pivot locknut and bolt securing the brake lever to the master cylinder, and remove the lever.
6. Disconnect from the master cylinder the:
- brake hose,
- brake light switch connections.
7. Release the clamp screws from the handlebar to remove the master cylinder.
Disassembly
1. Detach the rubber boot from the lever end of the cylinder.
2. Remove the circlip from beneath the boot.
1. Circlip
3. Remove the piston set from the master cylinder bore noting the relative position of the seals and piston components.
1. Master cylinder; 2. Spring and piston assembly; 3. Circlip; 4. Rubber boot
Inspection
1. Check the following for wear, damage, cracks or deterioration:
- Cylinder bore
- Rubber boot
- Spring
- Piston
- Pivot Bolt
2. Always renew the piston and seal set if the cylinder is dismantled.
3. Check that the two ports in the master cylinder bore are not blocked.
1. Ports
Assembly
Warning: Never use mineral based grease (such as lithium or copper based grease) in any area where contact with the braking system hydraulic seals and dust seals is possible. Mineral based grease will damage the hydraulic seals and dust seals in the calipers and master cylinders. Damage caused by contact with mineral based grease may reduce braking efficiency resulting in an accident.
Warning: Before installation, all internal brake components should be cleaned and lubricated with clean new DOT 4 brake fluid. Never use solvents, petrol (gasoline), engine oil, or any other petroleum distillate on internal brake components as this will cause deterioration of the hydraulic seals in the calipers and master cylinders. A dangerous riding condition leading to loss of motorcycle control and an accident could result if this warning is ignored.
1. Lubricate the piston and cylinder with new, clean brake fluid.
Warning: Ensure that the piston and piston seal are fitted facing the same way as noted during removal. A dangerous riding condition leading to an accident could result from incorrect assembly of the master cylinder.
2. Fit the new piston set into the master cylinder and retain with a new circlip.
3. Refit the master cylinder boot.
Installation
1. Locate the master cylinder to the handlebars and position the clamp with the 'UP' arrow pointing upwards.
1. 'UP' Arrow; 2. 'Dot' mark
2. Align the master cylinder/clamp split line with the 'dot' mark on the handlebar.
3. Tighten the clamp bolts, upper first and then the lower to 12 Nm.
4. Connect the brake hose to the master cylinder incorporating new sealing washers. Tighten the banjo bolt to 25 Nm.
5. Connect the brake light switch connections.
6. Position the brake lever ensuring that the pivot boss is correctly aligned to the push rod. Fit and tighten the pivot bolt to 1 Nm, and the locknut to 6 Nm.
Warning: Use only DOT 4 specification brake fluid as listed in the general information section of this manual. The use of brake fluids other than those DOT 4 fluids listed in the general information section may reduce the efficiency of the braking system leading to loss of motorcycle control and an accident. Observe the brake fluid handling warnings given earlier in this section of the manual.
7. Fill and bleed the front brakes (see page 14-12).
Warning: Always return the lever adjuster to the original setting noted during removal. Operating the motorcycle with lever settings which are unfamiliar may lead to loss of control or an accident.
8. Reset the brake lever adjuster to the original setting.
9. Examine the system for correct operation and fluid leaks. Rectify as necessary.
10. Connect the battery, positive (red) lead first.
11. Refit the rider's seat (see page 16-13).
12. Check for correct brake operation. Rectify as necessary.
Warning: lt is dangerous to operate the motorcycle with defective brakes; you must have your authorised Triumph dealer take remedial action before you ride the motorcycle again. Failure to take remedial action may result in reduced braking efficiency leading to loss of motorcycle control and an accident.