| A Symptoms | B Possible causes |
| 1. A pronounced hesitation or jerky movement during acceleration, deceleration, or sustained speeds. (not to be confused with engine surging or transmission related movements.) 2. A rolling "rumble" noticeable at low speeds, a high-pitched whine, or a "clunk" from a shaft drive component or vicinity of the shaft drive. 3. The shaft drive is locked up or no power is transmitted from the engine to the rear wheel | A. Bearing damage B. Improper gear lash C. Damaged gear teeth D. Broken drive shaft E. Broken gear teeth F. Seizure due to lack of lubrication G. Small foreign objects lodged between moving parts |
Note: Causes A, B and C may be extremely difficult to diagnose. The symptoms are quite subtle and difficult to distinguish from normal operating noises. If there is reason to believe these components are damaged, remove them for individual inspection.
Inspection notes
1. Investigate any unusual noises.
The following noises may indicate a mechanical defect:
a. A rolling "rumble" during coasting, acceleration, or deceleration, (increases with the rear wheel speed, but does not increase with higher engine or transmission speeds).
- Diagnosis: Possible wheel bearing damage.
b. A whining noise that varies with acceleration and deceleration.
- Diagnosis: Possible incorrect reassembly or too little gear lash.
Warning! Insufficient gear lash is extremely destructive to the gear teeth. If a test ride, following reassembly, indicates these symptoms, stop riding immediately to minimize gear damage.
c. A slight "clunk" evident at low speed operation. (not to be confused with normal motorcycle operation)
- Diagnosis: Possible broken gear teeth.
Warning! Stop riding immediately if broken gear teeth are suspected. This condition could result in the shaft drive assembly locking up, causing a loss of control and possible injury to the rider.
Troubleshooting chart
When causes A and B shown in the chart at the beginning of the "TROUBLESHOOTING" section exist, check the following points:
| Place the motorcycle on a suitable stand so that the front wheel is elevated and then spin the front wheel. Is the wheel bearing damaged? | YES → | Replace the wheel bearing. Refer to "FRONT WHEEL AND BRAKE DISC". |
| NO ↓ | ||
| Place the motorcycle on a suitable stand so that the rear wheel is elevated and then spin the rear wheel. Is the wheel bearing damaged? | NO → | Rear wheel bearings and shaft drive bearings are probably not damaged. Repeat the test or remove and check the components. |
| YES ↓ | ||
| Remove the rear wheel. Is the wheel bearing damaged? | YES → | Replace the rear wheel bearing. Refer to "REAR WHEEL AND BRAKE DISC". |
| NO ↓ | ||
| Remove and inspect the drive shaft components. |