These little fellows - full name: motorcycle fuel tap - control the entry and exit of the combustion chamber. They open to let in the air and fuel mixture, close to close the chamber when the mixture explodes and the piston is pushed down, then another set opens to let the gases out. exhaust. Most modern motorcycles have four valves per cylinder (two for intake, two for exhaust), although some Yamaha have five (three for intake), which if you've ever had to buy chocks for these valves, can make the operation rather expensive. In this article we are going to know how a motorcycle gasoline valve works, then we will mention the causes of some problems that affect this valve.
Motorcycle forks - General information
There are a whole bunch of motorcycle forks on the market that meet specific needs. So, before you get started, we advise you to take a look at our complete guide on the subject.
How does a motorcycle fuel tap work?
This is a valve that controls fuel flow in older motorcycles and some newer motorcycles. It usually has 2 or 3 settings (a few have 4). ON / RES / PRI / OFF.
The "ON" function
When your motorcycle is ON, it allows the use of most of the fuel in the tank (except what has been subdivided / designated as reserve), sometimes referred to as MAIN. This is the normal operating setting of the motorcycle.
The "RESERVE" function
When is in the RESERVE position, it allows all fuel to be accessible (including main fuel). If the setting was originally ON, then when the main fuel is used up the engine will start to run out of fuel (it loses power and sometimes it starts to run out) if not in use, it will run out of fuel. 'stop quickly. At this time, the driver can park (or, if he is experienced and is used to this motorcycle, put it on reserve). The motorcycle can continue to run for a few more kilometers (usually at least 30 kilometers, depending on the manufacturer's decision). When the reserve is depleted, it's time to call a tow truck; push or get a gasoline can to fuel the motorcycle.
The "PRI" function
For motorcycles that have the PRIME, this allows gasoline to flow freely (as if we were to pass the gasoline valve all together). In the ON and RESERVE position; these types of valves require a vacuum to allow gas to flow to the carburetor. As a BONUS, this is a special RESERVE setting that does not require any vacuum for gas to flow. Usually you only use it if the motorcycle has been idle for a very long time or if you let it run out of fuel (or after working on the carburetors). Sometimes this feature is used when there is a problem with the motorcycle and loss of vacuum, and on some motorcycles it allows you to drive home or off the highway if the motorcycle's fuel pump (for motorcycles that are equipped) breaks down.
Some newer motorcycles no longer have a fuel tap and, like motorists, rely on the driver to pay attention to the low fuel warning light (which usually goes off before reaching the reserve) and fetch fuel. 'gasoline before running out of fuel.
Why is a motorcycle fuel tap not working as usual?
Gasoline flows from motorcycle tanks (mainly) by gravity
By closing the fuel cock, you reduce the risk of gasoline leak when not in use. This reduces the risk of fire. Some older motorcycles are equipped with mechanical or electric fuel pumps. These motorcycles are always equipped with oil taps for safety. Early GoldWings had mechanical fuel pumps since the fuel tank was located under the saddle. However, these GoldWings actually rely on a combination of gravity and gasoline pump action to get fuel to the carburetors. Note: If the tank of an old GoldWing is half full, the fuel will flow to the carburetors by gravity… even if the engine is not running!
Your motorcycle's fuel tap is always ON
If you leave the fuel valve ON when not in use, you are completely relying on six sets of highly inconstant carburetor float valves to do their job perfectly! If these valves are not perfect, fuel can flow through them… causing an overflow that can eventually find its way (on some motorcycles) into the combustion chamber. Unlike air, fuel cannot be compressed. During the next attempt to start, a cylinder blocked by water may cause catastrophic engine damage. Like a bent connecting rod! This is serious punishment for not using your cock as intended!
Our recommended products:
Here are some recommended fuel taps for your motorcycle.
