Numerous aspects of motorcycle riding make it one of the most enjoyable pastimes, from the crisp air in your hair and breeze on your knees to the instant access to power a combustion-engine throttle puts at your fingertips.
For some riders, one of the highlights of ripping pavement is the royal roar of their bike motor.
Regardless of which moto-qualities you tend to focus on, there’s no denying that obnoxious whines, rattles, pops, and squeals minimize the experience.
But troubleshooting a motorcycle that makes strange sounds while riding starts with the nature of the sound, which is why we put together this solution guide to motorcycle noises.
Table of Contents
Why is My Motorcycle Making a Whining Noise?
Motorcycles make whining noises because of improper chain tension, faulty drive trains, compromised wheel bearings, faulty cooling system, or a corrupted gearbox, clutch, or transmission.
Faulty Cooling System
Low coolant levels, poor coolant quality, air pockets, blown gaskets, jammed lines, or leaking seals can cause a whining noise on a motorcycle with a liquid cooling system.
Liquid cooling motorcycle systems circulate in a quiet rhythm, so if your bike’s radiator or fan is whining louder than your motor, you may have a cooling system problem.
If you’re lucky, you may need to top off your coolant or change and replace it due to its poor quality.
Though, keep in mind, your motorcycle should not smell like coolant.
If you hear a whine from your motorcycle’s transmission, there is likely an issue within the gearbox. That said, your bike’s gearbox is a dynamic system of interrelating parts, which makes diagnosing the specific problem difficult without taking your gearbox apart.
One way to isolate the whining issue without opening your gearbox is to identify when your motorcycle makes the whining sound.
- If your motorcycle shines while you pull the clutch lever in and out and change gears, the issue is likely with the clutch and gears.
- If your motorcycle only whines when you shift in and out of a specific gear ratio, you can further isolate the damage to the particular gear.
- If the gearbox whine happens during all gear ratios, a worn gearbox bearing could be the culprit of your motorcycle whining noise.
Worn Wheel Bearings
A squeaking whine noise coming from the motorcycle’s wheels indicates worn wheel bearings, especially if the whine happens in rhythm with the wheel’s momentum and changes with their velocity.
Why is my Motorcycle Making a Popping Noise?
Misfires and backfires are the most common causes of popping noises on a motorcycle. A misfire is a pooping or chuffing sound within the engine cylinder caused by an incomplete ignition cycle.
A backfire is a loud popping coming from the exhaust caused by unburnt fuel combusting in your pipes.
What’s the difference between a misfire and a backfire?
- Spark misfires are caused by a failing spark or ignition system whereas fuel misfires result from blocked fuel or fuel system damage, and mechanically caused misfires to happen from engine damage.
- Backfires, on the other hand, are caused by excessive fuel or too little air, allowing liquid fuel to enter your hot exhaust system and combust.
While backfiring popping can damage your fuel efficiency, engine power, and performance, leading to complications over time, misfiring popping can cause severe engine damage sooner than later, depending on the cause.
You can distinguish a misfire from a backfire because a misfire comes from inside the engine and is often accompanied by violent engine vibrations.
If your bike makes frequent popping sounds, verify the cause before riding to avoid damage, collision, or injury.
Why is my Motorcycle Making a Rattling Noise When Accelerating?
If your motorcycle is making a rattling noise in unison with your throttle acceleration you may have low-quality or contaminated fuel in your tank.
If you hear external rattling during motorcycle acceleration, loose or missing fastener hardware could be the culprit, causing pipes, seats, foot pegs, or controls to rattle at high speeds.
Motorcycles also make clattering, rattling, or slapping sounds when throttling to accelerate if the cam chain or cam chain tensioner is worn.
The metal your bike’s cam chain is constructed from expands and retracts as it heats up and cools down from the friction of everyday use.
In time, this process wears the chain to the point that it can’t be tightened passed a certain point. The worn cam chain then dislodges from the gear teeth to rattle and clatter while you accelerate your motorcycle.
If the chain dislodges from multiple teeth, it can slap around and damage your engine.
- If the chain isn’t worn out, it might be looser than the service manual spec for your make-and-year model moto.
- Some motorcycle cam chains need to be tightened manually with the proper tools.
- Some motorcycles equip automatic cam chain tensioners that tighten the cam chain while you ride.
- If your automatic cam chain tensioner wears out, your cam chain can get loose enough to rattle and slap around while you ride.
Why Does my Motorcycle Chain make Noise?
All motorcycle chains make noise, the intensity and quality of which varies from bike to bike depending on the chain and sprocket design.
While some chains run loud and others run smooth, intermittent chain slapping and rattling indicate a problem.
If your motorcycle chain makes noises due to severe damage, poor adjustment, or interference, you may experience engine vibration coming up from your feet.
Here are the most common reasons a motorcycle chain makes noise:
- Improper motorcycle chain tension or gear tooth alignment.
- The chain is corroded, contaminated, kinked, or lacks grease.
- Chain rubbing against sprocket chain guard.
- Bent, cracked, or worn sprocket teeth.
- Loose sprocket hardware.
- Worn motorcycle chain.
Why Does my Motorcycle Make a Grinding Noise When Starting?
A motorcycle makes a grinding noise while starting if the starter motor starts okay but rubs against the flywheel and fails to engage completely.
Partial engagement may be enough to start your bike’s engine, but the rubbing and improper engagement damage the flywheel permanently.
The cause of the unfortunate grinding sound at start-up is either a worn or faulty starter, a worn or faulty flywheel, or missing shims between the starter and the motor, depending on the bike.
Most motorcycles start bolting straight to the motor, but if the gears get too close together, shims are sometimes used to prevent the grinding noise from happening.
Whether the starter or flywheel is at fault, every time you attempt to start a motorcycle that grinds when starting, you’re causing irreversible damage to your flywheel, and you’ll likely have to replace it.
Why is my Motorcycle making a Knocking Noise?
Motorcycles make knocking noises during premature combustion. The explosion prevents the piston from completing its cycle, crashing it into the side of your engine cylinder wall. Other causes include sideways-moving bearings, tapping valves, or a warped cylinder wall.
Without going into too much detail, your piston’s stroke cycle is powered by the combustion of air: fuel mix in your cylinder’s combustion chamber.
The combustion results from the air and fuel flow and precise engine ignition timing.
When the air: fuel mix ignites early, combustion occurs while the cylinder is still in the middle of its cycle, causing it to knock into the side wall of the engine cylinder.
Here are the most common reasons a motorcycle piston knocks into the engine cylinder:
- Improper Ignition Timing
- Lean Air: Fuel Mix; too much air and not enough fuel.
- Carbon deposits build up in the cylinder or on the pistons; carbon residue raises the internal engine temperature enough to ignite the fuel mix early.
- Low-octane, contaminated, or poor-quality fuel can’t handle the heat of a motorcycle engine and combusts early.
Besides premature combustion, severe engine overheating can cause the cylinder wall to warp inward and interfere with the piston’s cycle, causing knocking noises even when there’s no ignition issue. Poorly adjusted valves can stick out too far and crash into the piston.
Valve knocking is caused by poor cam chain timing or alignment.
Finally, a worn crankshaft bearing can wobble the crankshaft arm from side to side when brushed with force from the piston cycle. If it rocks hard enough, it can cause tapping and knocking noises on your motorcycle.
Why Does my Motorcycle Make a Buzzing Noise When Trying to Start?
Motorcycles make buzzing noises from under the seat if the battery is dead. The buzzing is often the sound of an electrical component switching on and off as the voltage dips more and more with every power failure.
The more you attempt to start a motorcycle with a dead or fried battery, the lower the voltage until the buzz becomes weaker.
- Use a voltmeter or multimeter to inspect the battery voltage with all your motorcycle’s lights on.
- If the meter reads less than 12 volts after a full battery charge, then the battery is likely dead.
- Inspect that the motorcycle battery’s terminal and wire connections make solid contact and are free of corrosion, dirt, or damage.
- Also, look for frayed or melted wires.
If your motorcycle’s battery is weak but not dead, it may have enough voltage to pull the relay contacts but not enough to hold them down and start the bike.
The battery voltage continues to micro-charge the relay, and the rapidly cycling starter relay causes a buzzing click sound.
Regardless of whether the cause of the buzz is the starter or a different electrical failure, a weak battery needs to be recharged, or the dead battery needs to be replaced before more electrical damage is caused by its inconsistent voltage.
Why Does my Motorcycle make a Clicking Noise When Rolling?
Motorcycles make metallic clicking sounds when rolling if their chain drive is corrupted, damaged, or dried. A motorcycle chain drive requires regular lubrication, especially after riding in wet, humid, or dusty conditions.
Another possible cause of a motorcycle that clicks while riding is a chain slacked too far to one side.
Motorcycle chain tension specification varies from bike to bike and must be adjusted evenly per the guidelines and measurements provided in the owner’s manual.
Finally, a worn or chipped sprocket can make a clicking noise while the chain rolls.
Why Does my Motorcycle Make a Clunking Noise When Accelerating?
Motorcycles make clunking noises when accelerating from deep within the motor’s bottom end if your bearings collapse, your crankshafts or conrods fail, or your engine is seized.
Deep clunking sounds when throttling and accelerating your motorcycle requires an immediate inspection from a seasoned mechanic.
Even if the clunking sound is intermittent, attempting to rev a failing or seizing engine can cause irreparable damage.
Why Does my Motorcycle make a Clicking Noise When I Try to Start It?
Motorcycles make clicking noises when starting if they have a dead battery, a faulty starter system, or a seized engine. A seized motorcycle engine results from severe damage and overheating and is less common than starter or battery failures.
For more information on this, check out our article about reasons why a motorcycle clicks instead of starting.