If your bike just isn’t running well, misfiring or just not having the power it should, the carb would be one of the main places where your issues could be. Of course, it’s well worth checking out the ignition timing and the spark first, but once you’ve confirmed those are in good order, it’s best to get the carburettor cleaned out and in good order.
Getting the carb sorted is actually quite an easy job and you’ll only need the basic tools along with a place to make a mess and some decent carb cleaner. Be sure to get a big can with a longer nozzle as this always helps to get into those smaller places.
Remove the Carb
All bikes are different, but the carb(s) are usually attached in a rather simple way. Most simply use 2 screws attaching it to the head of the engine. Be sure to remove the manifold with the carb as you need to inspect it for cracks and possible leaks.
Before you remove it, ensure the throttle line is detached and that the fuel line is removed as well. Take the carb out as level as possible as there will still be petrol in the float bowl.
Taking it Apart
A carb is really easy to take apart, but it’s always worth being careful when you open it and ensure noting jumps out that can’t be found again.
There should be around 3 screws holding the float bowl to the carb from the bottom. Once you remove these screws, you should see the jets, the float and the needle and seat.
This is where you would want to be and where all the action happens. First things first, inspect the float bowl for any dirt, dust and even sand as this would be a great indication as to the condition of the jets.
Remove and Clean the Jets
Most bikes only have 2 jets, the idle and running jet. There are some bikes with a third, which acts as a second stage at much higher RPM.
You’ll see the jets have a slot to fit a Philips screwdriver that you can turn anti-clockwise to remove it. The running jet has multiple holes in it while the idle jet is much simpler.
To clean these, do not use any brushes and don’t stick anything don’t the jet. All you need to use is the carb cleaner as these cans have more than enough pressure to blast them clean and get the dirt out. It’s well worth cleaning it on a white piece of paper as this would show if anything comes could and could be the reason for your problem.
Make sure you can see through the jet holes and ensure the carb itself it clean 100% before putting it all back together and getting it back on the bike. It might struggle to start a little, but as long as your idle and air screws are in the same position, you’ll get it going without any problems.