Do you have a carburetted motorcycle, moped, or scooter? Then you should know that it’s got something known as a “choke.” But what is it? And how do you use it?  In this blog post, you’ll learn:
  • What the choke is – and why carburetted bikes need one
  • How to use it

What is the choke?

The choke is an external toggle switch on motorcycles, mopeds, and scooters with carburetors.  When activated, the amount of air that enters the carburetor is restricted. While the airflow is restricted, an extra supply of gasoline or petrol is temporarily injected into the carburetor to aid during cold starts. Essentially, it’s a really, really strong cup of coffee – ready to wake the bike up from a deep slumber.

Why do carburetted bikes need one?

Unlike their fuel-injected siblings, carburetted motorcycles, mopeds, and scooters are sensitive to temperature.  Therefore, if it’s cold outside or the bike has been sitting for a while, the engine might struggle to reach operating temperatures and ignite the fuel mixture. That’s why the choke only exists for carburetted bikes. Fuel-injected motorcycles, mopeds, and scooters can deal with low temperatures better, and therefore don’t need them.

How to use a choke

The design of the choke varies from bike to bike. Some will have a button or a rod that you either press or flick with your finger to activate.

Others might have a lever that you have to squeeze the old-fashioned way while you’re starting your bike. 

For more information about how it works, watch this tutorial video from the Tomos America YouTube channel.

One last thing – once your bike has started, make sure that you shut the choke off (if it doesn’t shut off automatically). If you leave it on for too long,  your engine might start “running rich.” For more information on what “running rich” means, read the blog post about it here on The Dual Wheel Journey: