FAQ

How to rejet a motorcycle

Do I need to Rejet my motorcycle?

In most cases a rejet isn’t needed. Unless your bike was made to run dangerously lean from the factory, simple tuning of the idle mix will cover most of your throttle range.

What does Rejet a motorcycle mean?

When you jet your motorcycle’s carburetor, you’re setting the optimal ratio of air-to-fuel that goes into your engine. (This mix is called the stoichiometric ratio, which is 14.7 parts air to one part fuel. In reality, your motorcycle probably performs better at a slightly richer ratio.)

What does jetting a motorcycle mean?

In simple terms jetting your dirt bike’s carburetor is determining the proper air-to-fuel ratio the engine receives. Running the correct ratio of fuel and air makes your dirt bike run optimally. Installing jets of different sizes helps increase/decrease the fuel/air ration depending on what your bike requires.

How do you jet a carburetor on a motorcycle?

Take out the screws holding on the float bowl and remove it and its gasket from your carburetor. This should allow you to have access to the jets. On most carbs, you should be able to see the main jet in the center of the carburetor. This jet controls the amount of fuel when you’re at 3/4 to a wide open throttle.

Will running straight pipes hurt my motorcycle engine?

straight pipes arent that good for a bike, because when you let off the throttle, the sudden lack of hot gases being pushed out can cause cold air to be sucked in, which can damage your exhaust valves, and make for a VERY pricey repair. police will DEFINATELY like to follow and stop you often too.

You might be interested:  What causes motorcycle accidents

Do I need to Rejet motorcycle after installing new exhaust?

If you’re just swapping the exhaust with a new one of the same type, there’s probably no need to rejet your carburetor at all. Where it becomes an issue is when you are installing a stronger or tuned exhaust. Doing so raises the running temperature of your engine and more fuel is needed to compensate.

What does a jet kit do for a motorcycle?

A jet kit is a comprehensive assortment of jets that allows you to reconfigure your carburetor’s fuel delivery either to suit some specific purpose such as the installation of an aftermarket exhaust or airbox kit, or to correct some deficiency in the way the bike runs from the factory.27 мая 2016 г.

Do you need to Rejet carb with slip on exhaust?

If you just a put slip on pipe on it, you don’t have to rejet, but you will want to adjust your a/f screw, which requires getting to the carb. A previous post explained how easy it was to change the main jet.

What is FCR carb?

Keihin FCR Carburetors are acknowledged as the leading carburetors in 4-stroke motorcycle racing thanks to their precise metering high flow, flat slide throttle design and adjustable accelerator pump. … The Carb comes ready to bolt onto the bike’s stock airbox and intake manifold.

What happens if main jet is too big?

For example, using too large of a main jet will cause more fuel to enter the combustion chamber than it can efficiently burn. This will result in a “sputter” at full throttle. It could best be described as a rapid misfire.

You might be interested:  How to make a motorcycle seat more comfortable

Can you drill carb jets?

MopaR&D Nerd Member. Don’t drill them. Drills are about as accurate as measuring you cylinder bore with a ruler. If you are going to modify an existing jet, you need a reamer.

How do you adjust the air fuel mixture screw on a motorcycle?

Turn one air/fuel mixture screw in a clockwise direction with a slothead screwdriver with the engine idling until the engine speeds up. If the engine instead slows down, turn the screw in a counterclockwise direction until the engine speeds up.

What does raising the needle jet do?

The slide of a CV type carb is raised by vacuum which translates in to demand from the motor. Raising the needle in relation to the slide allows more fuel for the same amount of demand. Chopping the spring so that is weaker allows the slide (and the needle) to raise higher with the same amount of demand.

Leave a Reply

Your email address will not be published. Required fields are marked *