My Motorcycle Won’t Start, but the Battery Is Good

There’s nothing worse for a motorcycle rider than turning the key and hearing nothing, leaving them stranded and frustrated. A motorcycle that won’t crank the engine when the ignition is turned on typically means the battery is dead. The simplest solution is often just to charge or replace the battery. 

But what if the motorcycle still won’t start even though the battery is brand-new or fully charged? This is usually a sign of another mechanical issue. 

Learn the steps every motorcycle rider should know to diagnose and resolve frustrating no-start situations.

Verify the Battery’s Condition

Verifying whether the battery is dead or discharged can help prevent unnecessary diagnosis. If the engine doesn’t start when turning the key in the ignition, these tips can help determine if the battery is the cause:

• Visually inspect the battery: Potential signs of a bad battery include cracks, bumps, bulges, broken terminals, and signs of heavy corrosion, such as rust or buildup on the terminals.

• Check the headlight: If the headlight turns on brightly, as expected, the battery is likely in good condition. If the light is dim or won’t turn on, it may be a dead battery.

• Listen for odd noises: Turning the ignition on a dead battery should produce clicking noises or a short crank that does not start the engine. If the battery is good but the engine does not start, these sounds should be absent, indicating another problem.

• Multimeter testing: A voltage test with a multimeter can display the charge level on a 12 V sealed lead acid (SLA) or absorbed glass mat (AGM) battery. With the key removed from the ignition, plug the black lead into the COM port and the red lead into the V port, then set the multimeter to 20V mode. Then, touch the negative (-) port with the black lead and the positive (+) port with the red lead.
  
  If the voltage readout is 12.06 V or higher, the battery has at least 50% charge left and is likely still in good condition. Lower voltage levels usually indicate the battery is older and unable to hold a good charge; it should be replaced. 

If none of these tests have confirmed the battery is dead or needs replacement, the issue preventing the engine from starting is likely unrelated to the battery. Try the checks and fixes in the checklist below to diagnose common potential causes.

Verify the Fuel Tank

If the battery is good, it should power on the motorcycle’s gauges correctly even if the engine won’t start. Turn the ignition on and check the fuel gauge first; an engine that won’t start might simply not have enough fuel.

Check the Kill Switch

Most motorcycles produced since the 1980s include an emergency stop (E-stop) button, often called a kill switch. This button can typically be accessed from the right handlebar and is a safety device that can instantly cut power from the engine in emergencies.

Because the kill switch is easy to engage with one hand, it is relatively common to leave it on accidentally. Verify the kill switch is not turned on before trying to start the engine.

Pull in the Clutch Switch and Kickstand

Some motorcycle models are fitted with safety mechanisms that prevent the engine from starting when certain parts are in the wrong position.

• Clutch switch safety: Clutch safety switches stop the engine from starting if the clutch isn’t engaged, even if the gearbox is set to neutral. Experienced bikers often squeeze the clutch while starting the motorcycle out of habit to ensure the engine starts, even if it doesn’t have this type of safety.

• Kickstand safety: Some models are equipped with a safety that cuts off the ignition when the kickstand is down. This safety prevents bikers from starting the bike and accidentally damaging the kickstand while in motion. Fully retracting the kickstand should turn off this safety mechanism.

Inspect the Fuel System

If the tank has enough gas but the motorcycle still won’t start, it may be due to a problem with the fuel system. Potential components to check for include:

• Fuel filter: Fuel filters are designed to catch impurities and contaminants from the fuel, preventing them from reaching the engine. Over time, these filters can become dirty and clogged, restricting the flow of fuel and potentially preventing the engine from starting.

• Fuel lines: Bent or kinked fuel lines can also restrict fuel flow to the engine and prevent it from starting correctly. If the bending is minor, straighten the lines to remove the sharp angles. If it is more severe or the lines are cracked, they must be replaced.

• Petcock: Motorcycles equipped with a fuel control valve, or petcock, typically feature a manual valve at the bottom of the fuel tank. Manually operated petcocks, such as the type found on dirt bikes and older road motorcycles, usually have three settings: ON to enable the fuel tank, RES to turn on the reserve tank, and OFF to shut off access. 

Inspect the Spark Plugs

All combustion engines need spark plugs to function. The spark they produce turns the air and fuel they receive into the energy that powers the engine. 

If the spark plugs are fouled or corroded, they may fail to spark, causing the engine to receive air and fuel but no ignition. Check the owner’s manual to find the manufacturer’s recommended procedure for removing the spark plugs. Depending on the model, they may require the removal of side panels or other components to access.

If the spark plugs are fouled with carbon or grime, cleaning them with a wire brush should suffice. Gentle scrubbing is recommended to avoid damaging the electrode.

If one of the spark plugs is corroded or otherwise damaged, it is good practice to remove and replace all of them at once, as the other spark plugs may also be near the end of their lifespan.

Make All Necessary Checks Before the Next Ride

If none of these checks resolve the issue, a more serious mechanical issue may prevent the engine from turning on. The motorcycle may need the attention of an experienced mechanic for a more in-depth diagnosis.

Find detailed information about used motorcycles, UTVs, and ATVs at JD Power. Research models and trim levels from hundreds of manufacturers, view product photos, find detailed specifications, and get the most accurate resale and trade-in values.

Corentin’s passion for the automotive world started when he was just seven years old, during a life-changing visit to an auto museum. Now a seasoned writer, Corentin channels that early fascination into every piece he writes, whether he’s exploring the latest car trends or automotive history. But his expertise doesn't end there—he also brings his insights to topics like home improvement, the boating and yachting industry, personal finance tips, and cutting-edge tech.