Suzuki DR-Z70 Service Manual page 171

7-3 SERVICING INFORMATION
Complaint
Noisy engine.
Engine idles poorly.
Transmission will
not shift.
Transmission
jumps out of gear.
Symptom and possible causes
Noise seems to come from timing chain
1. Stretched chain.
2. Worn sprocket.
3. Not working tension adjuster.
Noise seems to come from clutch
1. Worn splines of countershaft or hub.
2. Worn teeth of clutch plates.
3. Distorted clutch plates, driven and drive.
Noise seems to come from crankshaft
1. Worn or rattling bearings.
2. Worn or burnt big-end bearing.
3. Worn or burnt journal bearings.
4. Too large thrust clearance.
Noise seems to come from transmission
1. Worn or rubbing gears.
2. Worn splines.
3. Worn or rubbing primary gears.
4. Worn bearings.
1. Valve clearance out of adjustment.
2. Poor seating of valves.
3. Defective valve guides.
4. Worn down camshaft.
5. Too wide spark plug gap.
6. Defective ignition coil.
7. Defective CDI unit.
8. Defective generator coil.
9. Clogged carburetor jet.
10. Idle adjust screw and air screw out of adjustment
11. Damaged or cracked vacuum hose.
12. Clogged air cleaner element.
13. Incorrect float chamber fuel level.
1. Broken gearshift cam.
2. Distorted gearshift forks.
3. Worn gearshift pawl.
4. Clutch release screw out of adjustment.
1. Worn shifting gears on driveshaft or countershaft.
2. Distorted or worn gearshift forks.
3. Weakened stopper spring on gearshift stopper.
4. Worn gearshift cam plate.
Remedy
Replace.
Replace.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Adjust.
Repair or replace.
Replace.
Replace.
Adjust or replace.
Replace.
Replace.
Replace.
Clean or replace.
Adjust.
Replace.
Clean or replace.
Adjust float height.
Replace.
Replace.
Replace.
Adjust.
Replace.
Replace.
Replace.
Replace.