A Kawasaki W175 with a noisy chain is usually too slack, too dry or running on worn sprockets. The low output of the engine means the chain rarely fails suddenly, but neglect still produces a rattle that sounds worse than it is.
Before you start
A chain that jumps a tooth can lock the rear wheel. Never inspect a moving chain, never reach near the sprocket with the engine running, and always refit the master-link clip in the correct direction.
Machine file Kawasaki W175
- Engine
- Air-cooled SOHC single
- Cooling
- Air
- Fuel
- Carburettor (verify the individual model)
- Transmission
- Five-speed manual
- Final drive
- Chain
Measure the slack
Put the bike on its centre stand or side stand as the manual specifies, then measure the chain's up-and-down movement at the midpoint between the sprockets. Compare it with the manual figure.
A chain that is too slack slaps the swingarm over bumps and can jump a tooth under load. One that is too tight loads the gearbox output bearing and wears quickly.
Noise and the part to check
| Noise | When | Check |
|---|---|---|
| Rattle over bumps | Rough road | Chain slack |
| Rhythmic tick | Once per wheel turn | Seized link |
| Constant dry rasp | All the time | Lubrication |
| Scrape at the sprocket | Constant | Alignment |
| Buzz at one speed | Steady speed | Chain guard |
| Squeak over bumps | Bumps only | Linkage or shock |
Lubrication and dry links
A dry chain is a loud chain. Apply a proper chain lubricant to the inside of the run, rotate the wheel and let it settle before riding, so the lubricant reaches the rollers rather than being flung off.
Rotate the wheel slowly and watch for a link that stays straight as it passes the sprocket. A seized link produces a rhythmic tick once per revolution and cannot be cured by lubricant alone.
Sprocket wear
Rear sprocket teeth wear into a hooked shape, and the chain then rides high in the valley instead of seating in the root. The front sprocket is smaller, turns more often and wears faster, but it is hidden by a cover.
A worn sprocket destroys a new chain quickly. Judge the set together and replace chain and sprockets as a pair when either is significantly worn.
Alignment after adjustment
The swingarm marks help, but they are not a precision measurement. A rear wheel that sits slightly crooked makes the chain scrape the side of the sprocket and wear its edges.
Confirm alignment with a straight edge or a string line, then torque the axle nut to the specified figure. Recheck the slack afterwards, because the axle often shifts as it is tightened.
Chain cover and guards
A chain cover traps dirt and makes a dry chain sound worse. Remove it periodically, clean behind it and inspect the guard for cracks or a missing mounting bolt.
A loose guard can buzz at a particular speed and imitate a drivetrain fault. Check the mounting bolts before chasing the chain itself.
When the noise is elsewhere
A squeak over bumps may be the rear suspension linkage, and a rumble that follows road speed may be a wheel bearing. Spin the rear wheel with the engine off and listen at the hub.
A rear brake that drags can also produce a rhythmic noise at the wheel. Compare the sound with the brake applied and released before ordering drivetrain parts.
The simplest test is to ride slowly on a quiet street and listen with the engine at a steady low speed. Chain noise usually keeps time with wheel rotation and changes when you open or close the throttle, while a bearing rumble stays constant and a brake noise follows the brake pedal. That one ride narrows four possibilities to one.
Keeping it from coming back
Adjustment and lubrication decide chain life on the W175. Measure slack with the bike as the manual specifies, clean and lubricate after rain, and check the slider and sprocket teeth. A chain that is too tight loads the output bearing; one that is too loose hammers the swingarm. Replace the set when the teeth hook.
A short checklist
- Measure the chain slack against the manual figure.
- Rotate the wheel and look for tight links.
- Check both sprockets for hooked teeth.
- Verify rear wheel alignment.
- Clean and lubricate the chain properly.
- Check the chain guard and its mounting bolts.
Questions owners ask
How often should I lubricate the W175 chain?
After a wet ride and at regular intervals in dry weather. A chain that looks dry or sounds raspy needs lubricant before the next ride, not at the next service.
Can I adjust the chain too tight?
Yes, and it is worse than too loose. A tight chain loads the output bearing and can damage the gearbox seal. Set the slack to the manual figure with the bike in the specified position.
Does a noisy chain always need replacing?
No. Slack, dryness and misalignment are all reversible. Look for seized links and hooked teeth before deciding the set is worn out.
