Trouble Diagnosis - Sym HD 125 Service Manual

14. BRAKE

Trouble Diagnosis

Disk Brake
Soft brake lever
1. Air inside the hydraulic system
2. Hydraulic system leaking
3. Worn master piston
4. Worn brake pad
5. Poor brake caliper
6. Worn brake lining/disk
7. Low brake fluid
8. Blocked brake hose
9. Warp/bent brake disk
10. Bent brake lever
Hard operation of brake lever
1. Blocked brake system
2. Poor brake caliper
3. Blocked brake pipe
4. Seized/worn master cylinder piston
5. Bent brake lever
Drum Brake
Poor brake performance
1. Improper brake adjustment
2. Worn brake lining
3. Worn brake drum
4. Worn brake cam
5. Improper brake lining installation
6. Seized brake cable
7. Dirty brake lining
8. Dirty brake drum
9. Brake pad worn in brake cam area.
10. Poor contact between brake arm and camshaft
indent
14-4
To this chapter contents
Uneven brake
1. Dirty brake lining/disk
2. Poor wheel alignment
3. Clogged brake hose
4. Deformed or warped brake disk
5. Restricted brake hose and fittings
Tight brake
1. Dirty brake lining/disk
2. Poor wheel alignment
3. Deformed or warped brake disk
Brake noise
1. Dirty lining
2. Deformed brake disk
3. Poor brake caliper installation
4. Imbalance brake disk or wheel
Tight operation or low return speed of
brake lever
1. Worn/broken/crack return spring
2. Worn drum
3. Dirty brake lining
4. Brake seized caused from dirty brake drum
5. Seized brake cable
6. Worn brake cam
7. Improper brake lining installation
Brake noise
1. Worn brake lining
2. Worn drum
3. Dirty brake lining
4. Dirty brake drum