Why Does My Motorcycle Vibrate? 8 Reasons (Solved)

For some, the purring oscillation of a rip-roaring motorcycle engine is a valued part of motorcycle riding.

But if your motorcycle starts vibrating to the point of feeling dangerous, unmanageable, or uncomfortable, it may indicate a problem with the bike.

Failure to fix a vibration-causing motorcycle issue early on can lead to a collision or severe engine troubles, eventually leading to total engine failure.

This article lists the most common reasons why a motorcycle vibrates and how to prevent it from causing severe problems. 

1. The Sprockets May Have Worn Out or Corroded

Your sprockets are the components responsible for turning the chain drive that powers your rear wheel. If either sprocket is warped, corroded, or run down from use, your motorcycle wheels will vibrate.

Note that:

• Your chain drive sprockets interact with the chain to spin the rear tire.
• Therefore, if worn or damaged sprockets are your issue, the motorcycle’s back tire will be the first part to vibrate.
• As the chain rolls across the uneven or corroded sprockets, it vibrates from the irregular rotation.

This chain vibration transfers to the rear wheel, becoming more pronounced as you accelerate until it affects the entire motorcycle with the pulse.

Inspecting your motorcycles from rear chain sprockets, cleaning any corrosion, and replacing the sprockets as needed could prevent your bike from vibrating while you ride.

2. The Tire Tread May Be Irregular

Worn tread on your motorcycle tires can cause a vibration that starts in the wheels but spreads through the whole front end as you increase your speeds while riding.

• Bent wheel rims, worn, uneven, or slashed tire tread, lodged road debris, or rough pavement damage are common ways motorcycle wheels are damaged enough to cause vibration, especially at high speeds.
• In other situations, technical riders ride curvy roads or tracks that force them to lean more on one side of their motorcycle tire, wearing one side of the tire tread faster than the other.
• Dragging your motorcycle tires by moving the motorcycle by hand or riding and braking aggressively can cause uneven tire wear, resulting in motorcycle vibrations.

Also, if the tire’s weight is unbalanced, or the wheel is tighter on one side than on the other, the wheel will shake back and forth as it spins.

Once you throttle up to high speeds, the shaking tire will cause the whole bike to vibrate.

An uneven tire installation is not only the most common cause of motorcycle vibration while riding, but it also causes uneven tire wear mentioned above.

The result is that the vibration worsens as the tread wears to match the uneven wheel weight or tension. In some cases, riders have their uneven tires fixed only to realize the tire needs to be replaced too, or the bike will continue to wobble under acceleration.

3. The Oil Level of Your Bike May Be Low

Oil and lubrication are essential to all machines, but maintaining the oil levels on a motorcycle engine is particularly important due to the various systems of fast-moving metal parts within its close quarters.

While some motorcycle designs have separate oil supplied for their transmission, the gearbox on many motorcycles is greased by the same engine oil reservoir.

• You’ll know a low oil level is why your motorcycle vibrates if the vibration starts inside the engine and you notice carbon deposits in your fuel and oil, as well as frequent engine overheating.
• The upsurge of friction and a lack of lubrication causes your motor’s cylinders, pistons, valves, clutch plates, and transmission gears to cause internal engine vibrations at first.

This inner vibration accumulates at high speeds, traveling up through the seat and handlebars to make the bike shake during your ride.

Inspecting and refilling your engine oil as needed before and after every significant motorcycle ride is part of common motorcycle ownership. Doing this helps to prevent engine vibrations by keeping your equipment properly lubricated and cooled down to a safe operating temperature.

4. You May Be Running Contaminated or Incorrect Oil

The various motorcycle engines used in the modern market call for different oil types. Running the incorrect oil class can cause engine and gearbox vibrations and increased friction, leading to irreparable damage.

The assorted oils come in various viscosity grades; some with additional additives and anti-corrosion agents. These specialty synthetic oils could be ideal for one motorcycle engine while inducing some severe failures for another.

The various types of motorcycle oils are categorized as either mineral, semi-synthetic, or synthetic. These classes include oils with various ratios of additives explicitly engineered for particular types of engines.

Note that:

• The varying oil classes expire at different temperatures, meaning that some will burn passed their point of effectiveness much sooner than others.
• Using burned or congealed oil or oil tainted with corrosion, water, dust, gasoline, or liquid coolant causes internal engine friction and an increase in heat, which makes some of the metal parts to expand.
• If left unresolved, this friction can trigger aggressive engine vibrations.

Preventing your motorcycle from developing an unsettling engine and gearbox grinding may be as simple as draining your oil, replacing it with the manufacturer-suggested oil, and keeping up with the service schedule outlined in your owner’s manual.

We’ve also written about why motorcycle oil smells like gas, if your bike has that problem.

5. The Chain of Your Motorcycle May Be Loose or Weak

An overly slacked, corrupted, or workout motorcycle chain will continue to loosen until it shakes or even slaps around. This risks damage to the surrounding components, and could lead to a dip in performance and increased vibrations while riding.

All motorcycle chains wear out eventually as a result of rapid expansion/retraction that happens to the metal as it heats up and cools down.

• The lack of standard service maintenance or leaving your motorcycle in damp areas can accelerate the deterioration and degradation rate of the chain.
• Once it’s slacked and degraded enough, the bike chain will lose its tension immediately upon heating up during everyday riding. This happens regardless of proper maintenance, lubrication, cleaning, and adjustment.

Inspecting and replacing your chain as needed is a good first troubleshooting step if your motorcycle vibrates unexpectedly while in motion.

Here are the most common symptoms of a worn or loose motorcycle chain:

1. Chain teeth are missing sprockets, and they roll over without engaging.
2. Irregular power transfer to the wheels generates unstable movement and increases engine vibration while riding.
3. Chain jumping, maybe even causing a chain slap.

6. Some of its Hardware May Be Damaged, Loose, or Missing

Failing to maintain your motorcycle fasteners, nuts, and bolts during your regular service inspection is a common cause of motorcycle vibration. This could put both the bike and the rider at high risk.

You should also learn about the typical reasons motorcycle starts shaking.

It is important to note the following.

• Loose or missing hardware in the wheel, forks, handlebar and swing-arm, and steering head parts cause wobbling in the front end that can translate to shaking across the entire motorcycle.
• Loose engine mounting bolts, plates, and head stays are the most common cause of increased motor vibrations.
• All bolts loosen and wear down due to the heat and engine stress of everyday riding.
• An increase in vibration may be gradual as the mounts loosen one after the other.
• Once one piece of hardware gets loosed, however, the surrounding fasteners take on the extra work and are compromised in the process.

In view of the above, putting a wrench on every single critical engine fastener is a part of routine maintenance on any motorcycle.

Failing to inspect and torque all your motorcycle’s hardware to spec during every service can cause an increase in aggressive front-end wobbling. It could also make the engine to start shaking and can sometimes result in a collision, injury, or even worse.

7. Your Tire Pressure May Be Incorrect

Inadequate tire pressure causes tire deflation and affects your tire’s grip on the road, as well as your motorcycle’s handling. Riding on improperly inflated motorcycle tires can cause a decrease in performance and handling, leading to aggressive motorcycle vibrations at high speeds.

Checking your tire’s PSI levels before and after every significant motorcycle ride is part of being an accountable motorcycle owner.

If there is no call for concerns, you should inspect your tire pressure once a week, as it changes with subtle shifts in precipitation, elevation, air pressure, and ambient temperature.

Riding on improper PSI adds extra stress to your bike’s motor, causing it to work harder, get hotter, and go through fuel and sometimes even oil faster.

And finally, improper PSI also causes vibration to your wheels, which can travel up to your handlebars from the front wheel and into your seat from the rear, risking a sudden loss of motorcycle control.

In extreme situations, the aggressive front wheel wobble caused by inadequate tire inflation can shake the handlebars so violently that they hit the fuel tank and cause the rider to crash.

It, therefore, becomes important to note that maintaining proper tire pressure will keep your motorcycle vibrations down to a minimum.

8. The Bearings May Have Worn Out

If your bike frame’s swing arm bearings rust, incur damage, or wear from the stress of everyday use, your motorcycle will vibrate, especially while riding over loose gravel or damaged roads.

Failed Steering Head Bearings absorb vibration from the front end and cause vibrations when you move your handlebars.

If busted bearings are the reason your motorcycle jerks while riding, you need to replace the worn bearing immediately before riding.

Note that:

• Worn steering head bearings can vibrate back and forth at the touch of the handlebar when the bike is in motion, risking collisions when cornering and turning.
• If swing arm bearings are the culprit, you may notice the vibration stops on smooth roads but picks up when riding on loose gravel, over rough pavement, or in the wind.

Make sure to also check out our article about why motorcycle front wheel wobbles.

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