Is It Bad To Push Start A Motorcycle?


We’ve all seen the classic bobsledder approach to starting a motorcycle. Have you ever wondered how to do this or if it’s bad for the motorcycle? Luckily, we live in a time with motorcycles that are fuel injected and have an electric start, but not that long ago we had motorcycles that were only kick started, and before that, early motorcycles were only push start. 

So, is it bad to push start a motorcycle? As long as the transmission and clutch are in good condition, it is not bad for your motorcycle if you push start it correctly. However, this should not be done frequently and underlying starting issues should be addressed as soon as possible.

Understanding the mechanics behind push starting and the implications for different situations provide valuable insight into the practice’s safety and effectiveness. We’ll discuss more about why it isn’t necessarily harmful for your motorcycle to push start it, how it works, and things to avoid while doing this.

Why It Isn’t Harmful To The Transmission Or Clutch

Like I said earlier, push starting a motorcycle isn’t ideal. It takes a bit of work, sometimes more than one person, but it won’t out right damage the transmission and the clutch. This being said, just because push starting won’t wear out the clutch or break the transmission, when we notice starting issues with the motorcycle that are related to the battery, we should fix the problem as soon as possible.

When we start a motorcycle, we want to start in second gear because by doing so, we are limiting the drive train shock that is felt on the bike when compared to first gear. Drive train shock, whether that comes from improperly shifting the transmission, or having a clutch that cannot fully disengage gears, we can damage the transmission. 

When the gears of a transmission grind, it is called gear clash. Gear clash can be extremely damaging to the transmission, but gear clash WON’T occur during a push-starting event. When push starting, the transmission will sit in neutral, and then get ‘tossed’ into second gear. Doing this may put strain on the gears of the transmission, but with most healthy transmissions, this won’t cause anything bad to happen.

The same is with the clutch. Will push starting a motorcycle place wear on the clutch? Yes, but the wear put on the clutch is almost negligible because of how minor the wear would be.

Push starting a motorcycle will be more difficult if you are noticing that the clutch is wearing out or beginning to slip. In order to be pushed to start, the motorcycle needs to have a healthy clutch so when the transmission is engaged, it will be able to hold long enough for the engine to turn.

How Does It Work?

Push-starting works on motorcycles and cars that are equipped with a manual transmission, and an engine driven alternator. If you have a scooter that has a CVT or a car with an automatic transmission, push-starting isn’t an option.

With a motorcycle, how it works is very similar to a car. If you’ve verified that the battery is the problem with the motorcycle, then you need a way to turn the engine over in order to have the alternator start to charge the battery. If we look at the engine, it has what’s called a crankshaft, and it’s the crankshaft that both drives the alternator, and also has an input shaft to the transmission.

The usual flow of power happens when the pistons move and then rotate the crankshaft, the crankshaft runs the alternator and then inputs to the transmission, which then transmits power to the chain and sprocket and powers the rear wheels. When push starting a motorcycle, you try to do all of that in reverse

Starting with the wheels, as the motorcycle is moving, it is sending power from the wheel to the chain, to the transmission. The transmission will be in neutral, but it will be sitting in the correct gear ratio, and in this case, it is second gear. When the clutch is ‘dropped’ or quickly released, the transmission puts power through the crankshaft, which then turns the alternator, and moves the pistons, and allows the battery to now signal the injectors/spark to ignite.

How To Properly Push Start A Motorcycle

To push start a motorcycle, you should have at least one other person around to help push it. If you’re by yourself, this process is made much easier when you are going down an incline. Before you start pushing, make sure that your motorcycle is in second gear.

With second gear chosen, hold in the clutch and start moving your motorcycle forward. Maybe this means to start rolling downhill or having your friends push it. I’ve personally found a ton of success doing this while going downhill. Push or ride the motorcycle until you’re going around 10 miles an hour.

You want to sit around 10 mph because any less than that won’t be fast enough to engage second gear. What will likely happen is you will release the clutch and the bike will jerk to a stop and not turn over. Going over 10 mph just ensures you ample time to turn the engine over. 

Once you are going at least 10 mph, quickly release the clutch. It’s important to have your friends stop pushing right before you release the clutch. You need to release the clutch quickly because you want enough torque on the crank in order to start moving the pistons.

When you release the clutch, you want to simultaneously push the start button. When the clutch is released, the engine will begin cranking, so you want to push the start button to have the engine start while it’s cranking. Once the engine turns over, pull the clutch back in and rev the motor up.

Don’t rev it all the way, but maybe hold it around 2000 to make sure that the battery will hold. The battery might take a while to charge off of the alternator, so don’t turn it off. Make sure it has enough time to idle and charge before turning it off again.

Remember that charging a battery won’t fix a worn-out battery. Batteries can only be jump started or push started a couple of times before it’s time to replace. So once your motorcycle is running, you should be prepared to replace the battery, or ride it to a place that you can properly fix your motorcycle.

Things You Should Not Do When Push Starting A Motorcycle

The most common mistake when push starting a motorcycle is misdiagnosing the battery. You can find example after example online that shows people trying to push start their motorcycle when they were out of gas, not dealing with a bad battery.

I even saw a post of a guy who was out of gas and then killed his battery when he was trying to push start it when all he needed was some gas. So, make sure you verify the problem with the bike is battery related, not spark or fuel related.

Another thing to be careful of when push starting a motorcycle is that you should be careful where you are pushing it. You shouldn’t do it inside an intersection, you should do it in a place that gives you enough room on the road to push it and jump on it.

Also, the jerk that comes from the push can sometimes put you off balance, so be prepared for that so you don’t fall over once it starts up. Finally, make sure that when you release the clutch your friends who are pushing you have their hands off the motorcycle. When it kicks up, the shock might hurt their wrists or their arms. 

Conclusion

While push starting a motorcycle can be a useful technique to get back on the road when facing a dead battery or faulty ignition, it’s essential to approach it with caution and consideration for the bike’s mechanical components. While push starting is generally safe for most motorcycles, repeated or improper attempts can potentially cause damage to the engine or transmission.

Have you guys ever push started a motorcycle? Do you have any other tips or tricks you’d like to share? Feel free to comment below or send us a direct message!

Kyle Cannon

Kyle currently works as a mechanical engineer and graduated with a minor in automotive engineering. He loves restoring motorcycles, has a vast knowledge of how they work, and has sold his restoration projects to customers from all over the United States.

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