7 Reasons Your Motorcycle Won’t Start (With A New Battery)

It’s Saturday night and you are fired up about ripping some wheelies on the Sunday morning ride you have planned. You are preparing the bike the night before but panic begins to set in as you hit the starter but the bike won’t turn over.

The auto parts store is still open so you frantically track down a replacement battery because “it has to be a bad battery, right?” Of course, it’s not.

You have no choice at this point but to put your technician hat on and begin diagnostics. Fortunately, you have google which pointed you here to work through some logical progressions to light the candle and stay on track for the ride tomorrow.

First, identify if this is a crank or no crank no start diagnostic. Simply put, when you hit the starter button, does the engine crank over, or is it just crickets.

This will take us down one of two paths at which point there are some common culprits for this issue. If your bike cranks but doesn’t start, work through steps 1, 2, 3 then 5. If your bike does not crank over, start with 1 then go to 4 and 6. 7 is the last step in all circumstances.

In general, if your bike doesn’t start with a known good battery, you either have an issue with air, fuel, or spark. There are some actions we can take to pin down which system has failed and how to make a good lasting repair.

1. Obvious Issues

I’m not going to waste your time filling up this whole article with obvious items you have hopefully already checked. From a beginner’s perspective, I still want to take a moment to list some of the common items that will prevent your bike from starting without anything actually being wrong.

  • Kill switch is in the on position

This may sound trivial but it has happened to me before so I’ll list it. If you turned off your bike after the last ride using the kill switch, there’s a slim chance you flipped it back to the “off” position. Next time out the bike won’t start because the kill switch is “on”.

  • Bike is in gear with clutch engaged

If your bike is in gear rather than neutral and you don’t have the clutch lever pulled in, the bike will not start. This is a safety feature so the bike doesn’t launch out from underneath you when you start it in gear with the clutch engaged.

  • Key is only turned to “accessory” mode not all the way to “start”

Again, embarrassingly, I must admit that I once sat on my first bike (2012 Yamaha FZ6R) for several minutes trying to figure out why the f*@! it won’t start and it ended up being that I didn’t turn my key all the way to start. “Accessory” mode will turn on the lights and dash but not actually start the bike.

  • Bike is out of gas

If the bike is low enough on fuel, there’s a possibility it got you home but the next morning won’t start up. If you forgot what you had left, pop the gas cap open and shake the bike a little to see how low the level is.

  • Fuel petcock not turned to “on” position

On older models, there is a fuel petcock that has to be manually turned “on”. If “off”, fuel will never make its way to the engine as it will be blocked off by the petcock.

This will now effectively begin the diagnostic portion of the article. If you didn’t make a simple blunder, we need to figure out what part failed and how to rectify the situation.

Read through all the diagnostic steps before performing repairs. Depending on the symptoms you’re observing, your issue may be simple but just further down the list.

2. Poor Maintenance

Lack of maintenance or poor work quality when performing services to your bike can definitely cause a no-start condition. This is the best place to start because most maintenance items are simple and easy to perform.

Diagnosis

If you’ve owned the bike a while, you should have been performing regular service on items like the air filter and spark plugs to keep your bike in good running condition.

Old fouled spark plugs and a dirty clogged air filter can cause your bike to crank over but not start. The engine needs a good flow of clean air to mix with the fuel inside the combustion chamber and run the engine. It also needs a strong spark to ignite the mixture.

Replacing spark plugs or an air filter are very basic tasks and need only simple tools. If you don’t wrench on your own, this is something that can be added to a routine service visit that won’t break the bank.

If you just purchased a bike that will not start, consider how long it may have been sitting and consider an inspection of the carburetor.

Carburetors have long since been replaced by fuel injection, but many bikes on the road today still make use of this dated technology. Carburetors are very finicky and cannot be left sitting for very long for the risk of getting clogged.

They have very small fuel jets and orifices that can get clogged easily with debris and old fuel. If your carbureted bike cranks over but doesn’t start, and you haven’t performed cleaning in a while or just recently purchased it, start here.


I hesitate to list this final cause in this section, but I do believe it’s a maintenance item, although some might disagree. Especially on high-performance sport bikes, the timing chain and tensioner should be considered maintenance items that need to be serviced at mileage intervals.

The timing chain tensioner is a simple device that puts the timing chain under tension so it does not slip off the camshaft teeth. These components are inside the engine and require more than some technical prowess to replace if you plan to do it yourself.

Diagnosis

I personally had an experience purchasing a new to me used bike that would not start. It was old enough to where I found it reasonable to pop the valve cover off and inspect the valvetrain. The side of the cam gears has little marks to align with the chain to “set the timing”.

Just so happens the chain had jumped off the gear and slipped a couple of teeth. This causes the valves to open and close at the wrong time (get it, timing chain) which will result in the bike not starting.

The reason for this was the tensioner had failed (instead of being under tension it was floppy) so the chain had too much play and slipped off the cam gears allowing a few teeth to spin by before it reset.

Repair

In order to properly service or repair this system, start by removing the valve cover of your engine. You will need to remove the gas tank and airbox to gain access to the valve cover which is held on by a few perimeter-mounted fasteners.

With the valve cover off, you should see the camshafts, which will need to be removed.

The chain rides on the camshaft gears just like the drive chain on your sprockets on the outside of the bike.

The chain meets up with the crankshaft at the bottom of the engine where there is another sprocket.

The timing chain tension will be mounted in alignment with the chain with a plunger sticking out inside the engine to provide tension on the chain. The tensioner is typically held on with two bolts that are a nightmare to access.

I would recommend replacing the chain and tensioner if the bike is under-serviced or if the chain jumped teeth.

3. Fuel System

Assuming the bike is up to date on maintenance, the next place I would look is the fuel system. There are several parts involved with providing the correct amount of fuel at the proper rate to the engine.

Also assuming there’s gas in the tank, the fuel pump delivers gas from the tank to the fuel injectors to be deployed into the combustion chamber.

Diagnosis

First, assess the quality of fuel in the tank and how long the bike has been sitting. Old fuel can clog up your injectors and gum up the fuel point which may provide enough added strain which will cause it to burn up and fail altogether.

If the gas is fresh, check your fuse panel. There is a fuse that will be labeled accordingly for the fuel system and can be simply removed and visually inspected for failure.

When you turn your key on, you should hear the fuel pump prime with a whirring sound coming from the tank that lasts a few seconds. If you don’t hear this, you know you have a fuse or pump problem.

Fuses are cheap parts that will be labeled with a number indicating the amount of amperage that can pass through before breaking the circuit. This is a safety measure so that a current spike doesn’t damage major components like the main computer.

Repair

If your bike is carbureted and the gas is old, you can stop here. You need to pull that carb apart and do a deep cleaning in addition to replacing the rubber seals. I recommend finding a shop with a sonic cleaner that can fully immerse the carburetor and get every orifice and channel fully cleared of debris.

A wiring short or bad ground will be to blame for a blown fuse. You may have caused this issue when replacing the battery or possibly if any aftermarket electrical work has been performed. It is not uncommon for light kits or extra electrical accessories that are poorly grounded to blow fuses.

It is not common for fuel injectors to clog on modern bikes. If you know your bike will be sitting for an extended period, drain the fuel or add a fuel stabilizer. You can also let the bike idle with some fuel injector cleaner. Manually removing the fuel injectors and performing a cleaning is not ideal but can be done.

The fuel pump is easily accessible inside the base of the fuel tank and isn’t too expensive. If you found a blown fuse and replaced it but the pump still doesn’t prime, I would wing it and just replace the pump.

4. Starter

After checking off any fuel-related concerns, the starter is the next logical place to go. This may or may not cause a no-crank no-start issue depending on the failure.

If when you attempt to start your motorcycle you hear a loud whining or whirring noise or a loud click, first inspect the starter motor.

Diagnosis

You may be able to get a failed starter to spin up by striking the outer housing with a hammer. This is not exactly high-level professional technique but has worked for me once before in identifying a failed starter motor.

The starter motor is mounted to the outside of the engine so it is easy to identify and inspect. A failed starter might make a loud click because it is bound up, or a loud whining noise if the teeth are sheared off.

Repair

Starters are simple to replace with a standard set of tools. As mentioned earlier, they are externally mounted mechanical components held on by fasteners.

5. Exhaust System

A less common failure but still a possibility and easy to identify is a clogged or damaged exhaust system.

Just as mentioned previously, your engine needs proper airflow to function correctly. Both air coming in through the intake past the air filter, as well as air exiting through the exhaust, is critical to engine function.

You may hear people talking about “proper back pressure” being an issue with exhaust modifications. This is because the engine relies on a certain balance of exhaust flow just like intake flow to run right.

Diagnosis

A simple visual inspection will go a long way in this step. You want to check the headers and muffler for any external damage. A pinched pipe can restrict airflow to the point of causing a no-start condition.

Additionally, inspect the muffler for excess debris that might be clogging the exit pipe. I’ve even seen the baffling inside the muffler be chewed by rodents and used to make a little home inside the muffler. All of that material bunched up in the muffler completely blocked off the exhaust.

Repair

Depending on the severity of the issue, repair or replacement will be valid. If the exhaust pipe is slightly deformed, you may be able to reshape it and save the exhaust. If the muffler is destroyed internally, you can clear the blockage, but you will have a much louder exhaust as a result.

6. Electrical Issues

This is definitely the most involved portion of the diagnostic process which is why I want you to check off boxes 1-5 before getting here. If nothing has been out of whack up until this point, we need to start inspecting some electrical components to trace this no-start issue.

  • Fuses

In step 3, you inspected the fuel-related fuses and checked for any indication of a short circuit. Now would be the time to pull the remaining fuses to inspect the internals. You would be shocked how a seemingly unrelated fuse could cause a no-start condition.

  • Ignition Coils/Wires

This wouldn’t be a bad thing to visually inspect back in step 2. Spark plug wires can become brittle and break apart over time, especially on older models. This would be something obvious when servicing your spark plugs and can cause no spark meaning no start. If you have a failed coil, typically all won’t fail simultaneously so you will have a misfire / rough idle instead of a no-start issue.

  • Kill Switch

The kill switch on the right-side handlebar can fail and cause the bike to have no spark. A kill switch can be quickly disassembled and inspected for bad connections, broken wires, or bad contacts. A multimeter should be used in electrical diagnostics to pinpoint circuit failures.

  • Starter Switch

The starter button is typically on the same housing as the kill switch, so the same principles apply here.

  • Kickstand Switch

This switch is mounted to the hinge point of the frame and side stand and is responsible for killing the bike if gear is engaged and the stand is down. The problem is this switch can fail too which may result in an undesirable no-start condition.

  • Clutch Lever Switch

Same idea here as with the side stand switch. The clutch switch is designed to require the clutch to be pulled to start the bike when in gear to avoid an undesirable surprise launch.

  • Ignition

This isn’t as common as some of the other items but worth noting as it has happened before I’m sure. The ignition receives power from the battery and is switched “on” using the key. The wires run up from into the ignition and can sometimes get bound in the steering neck, so when you turn back and forth the wires might pull loose from the ignition causing a bad connection. If you have an issue with the ignition, nothing will light up or prime and the bike has no chance of starting.

  • Wiring Harness

At this point, the bike needs to be at a shop unless you’re trained in this subject. A proper wiring harness diagnosis is not an elementary task and can be very time-consuming. On my own, all I would do is inspect for obvious spots of wires being pinched or damaged from impact.

7. Catastrophic Failure

Alright, we made it to the end. You went through my 6 steps to freedom and unfortunately came up short. If you’re here then nothing simple is the matter. There may be other small nuanced items that I missed in my sections above, but ultimately a catastrophic failure means either the engine completely locked up or has no compression.

Some engines with little to no oil maintenance will seize up from broken internal components. Additionally, poor lubrication can cause loss of compression which will also cause a no-start condition.

Either way, we’ve hit the end of the road and that Sunday ride may turn into a dealership visit instead.

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