4 Stroke Dirt Bike Won’t Start? (Common Problems & How to Fix)

The most common reasons why a four-stroke won’t start. It’s crucial to start by working through the basic items first, then work your way through the more challenging (costly) objects. If you’re able to start here, you’ll soon be able to get your dirt bike going without much effort.

  • Gas is turned OFF
  • No gas / old/bad gas 
  • The jet in the carb is faulty
  • The battery needs to be replaced/charged
  • No spark from plug / fouled spark plug
  • Faulty kill switch
  • Choke not working
  • The carburetor or fuel injector is clogged/dirty
  • The air filter is dirty 
  • Low compression

If your four-stroke has spark and fuel but isn’t starting, it is recommended to go through the following list before making your bike an appointment with the hands of a mechanic.

4 Stroke Dirt Bike Won’t Start

How to Start a 4 Stroke Dirt Bike?

Starting a Cold 4 Stroke

  • The fuel valve should be turned ON.
  • Change the transmission to neutral.
  • If the ambient temperature falls to 35 degrees Celsius (95degF) or less, you can remove the choke knob completely.
  • If the temperature falls below zero degrees Celsius (32degF), start the engine twice or thrice. (The engine needs a more rich mix to start in cold temperatures. When the throttle is open, it will trigger the accelerator pump to supply additional fuel to the engine and help it start in cold temperatures.)
  • When the throttle is closed and the throttle closed, start the Kickstarter starting at the beginning of the stroke, then kick it through until the bottom, using the same speed and continuous movement. (Do not open the throttle, as the carburetor comes with the accelerator pump; excess fuel is injected into the engine, while the spark plug could be plugged when the throttle is open and closed over and over. Insufficient combustion fuel can make it difficult to kick-start.)
  • Within a few minutes after the engine is started then, pull the throttle knob back to the full off. If the idle is not stable, then open the throttle.

Starting a 4 Stroke While Out Riding

  • Change the transmission to neutral.
  • Take the hot start lever and then kick-start the engine. (Do not turn the throttle.)
  • Once the engine has started, let go of the lever that is hot to start.

Starting a Hot 4 Stroke

  • Switch the fuel valve ON.
  • Change the transmission to neutral.
  • The hot start lever should be pulled and start the engine. (Do not release the throttle.)
  • Once the engine is running, pull back the hot lever to start.

Starting a Flooded 4 Stroke Dirt Bike

If you’ve tried to get your bike started for a long time (and using gas when you should not), but you’re still trying to get your bike to start, you could be in flood.

If your dirt bike isn’t starting, try this:

  1. The bike should be able to rest for 5-10 mins.
  2. Check that the choke is not in place.
  3. Check that the ignition is switched on.
  4. Keep the throttle open wide.
  5. Kick (or push to start) on the engine to start it turning over
  6. Once the engine has started, release the throttle. 

Spark Makes Things Happen

Your dirt bike might be getting fuel and air; however, if it doesn’t have a spark, it’ll never desire to begin. 

An easy method to tell if your dirt bike is spark-free:

  1. Remove the spark plug from the engine.
  2. Put the cap back on the spark plug.
  3. Resting the spark plug on the engine.
  4. Slowly kick/turn the engine over.
  5. You may need to turn off the garage lights to see it.
  6. Look for a small, blueish spark of electricity on the end of the spark plug.

If you are still looking for indications, you should be ready to swap out components if you don’t wish to replace your electrical systems completely.

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