The reserve fuel switch, also called fuel petcock valve, or simply fuel valve, is used to control the fuel flow from the tank to the engine. ... 'OFF', 'ON', and 'RES' positions of the valve. When these valve positions are used.

What is the purpose of a motorcycle Petcock?

A petcock, or sometimes referred to as a fuel tap or fuel valve, is a 2 or 3 way valve on the bottom of your fuel tank. It works by directing fuel from your tank to the carburetors or fuel injectors. Fuel is pulled by either gravity or vacuum from the fuel system.

How does a motorcycle fuel Petcock work?

It uses engine vacuum createdwhen the engine is running to pull back a small piston that allows the fuel to flow. When the engine shuts off, the vacuum is removed and the fuel shuts off. ON is the position for normal operation and the position you return to after refueling the bike.

Should I turn off the fuel on my motorcycle?

The primary reason for shutting off the fuel is safety. On a motorcycle the fuel tank is directly above the engine. If fuel were to leak it would drip directly on the hot engine. This along with the fact that most motorcycles use a rubber supply hose that is exposed to the engine heat and the resulting decomposition.

Is it bad to let a motorcycle sit?

If unused, over time your motorcycle battery will drain. There is a phenomenon called “parasitic drain” where the motorcycle computers and poorly grounded wires cause slight discharge. ... If you let your motorcycle sit for long periods of time, this will completely drain the battery.

Petcock Tutorial

24 related questions found

How long can fuel sit in motorcycle?

Unstabilized gas in a motorcycle can start going bad in about 30 days, especially when it is not being used. The exposure to oxygen eventually changes the chemistry of gas which can lead to gum and varnish deposits. Gas should not be used if it has been sitting for longer than 6 months.

What does Prime mean on a motorcycle?

The "Prime" setting lets you flow fuel directly to the float chambers filling them without having to turn the bike over. On vacuum controlled petcocks the intake's vacuum opens a diaphram and lets the fuel flow past the petcock, so you need to turn the engine over to create that vacuum.

What does PRI on a fuel petcock mean?

PRI is for priming the carburetor. That means filling the carburetor up with gas if it is say the first time its ever been ridden or the gas was drained out for some reason.

How do I know if my petcock is bad?

Re: How to tell if a petcock is bad? If the bike runs on RES and PRI but has issues running in ON,then the petcock is bad. If you disassemble the petcock,you will more than likely damage the internal diaphragm.

How do you tell if petcock is on or off?

Counter clockwise is "OFF". Clockwise is "RESERVE". Check it by turning to the off position and pull off the gas line. If it doesn't flow then you have it.

Does a motorcycle need a fuel pump?

On modern motorcycles, an electric fuel pump is required to create the pressure required for fuel injection. ... Engine vacuum is used to operate a fuel pump by pulsing a diaphragm as described above. Since the vacuum of the engine has a bit of a pulse, the pump can flow fuel to the carburetor through all RPM's.

What happens if you leave the choke on overnight?

What Happens If You Leave The Choke On Overnight? Nothing will happen if you leave the choke on overnight. Since the engine is off, the carburetor isn't in operation and nothing is moving internally in the engine no harm will come.

When should I put my bike on reserve?

ON -At "ON" position fuel will flow from fuel tank to the carburetor. RES -At "RES" position fuel will flow from the reserve fuel supply to the carburetor. Use the reserve fuel only when the main supply is exhausted.

Is it bad to run motorcycle on prime?

Prime is not good long term. If you have a carb problem you now have a chance of your petrol pouring out all over the floor. I had the tank off two weeks ago to clean it, also cleaned fuel tap and filter whilst I was at it, but the tap was fine then. I dropped the bike off with him running fine in the "on" position.

How do you prime a motorcycle fuel pump?

Priming the Fuel System

1. Fill the fuel tank.
2. Turn the ignition key to the ON position.
3. Move the engine stop/run switch to the RUN position.
4. Allow the fuel pump to run until it stops (about 2 seconds).
5. Move the engine stop/run switch to the STOP position.
6. Repeat steps 3–5 four to five times.

Should I store my motorcycle with a full tank of gas?

A full tank is essential for keeping moisture down on the tank walls. After the tank is full, add a fuel stabilizer and then take the motorcycle for a short drive to the storage destination. ... We recommend this method if you plan on storing your motorcycle for six months or more.

Should I start my motorcycle every day?

All motorcycle owners should start and run their motorcycles for at least 15 minutes once a week during the winter. Letting it run will keep all the engine components and gaskets lubricated, eliminates condensation buildup, ensures the carburetor will not gum up, and recharges the battery.

How often should I ride my motorcycle?

To keep progressing and improving your fitness, you ideally need to be riding your bike every two-three days, even if it's just a turbo trainer workout. The minimum you can get away with and still see significant fitness gains is three rides a week.

At what age should you stop riding a motorcycle?

The age at which motorcycle riders should stop riding a motorcycle is dependent on their physical, mental, and overall health condition. The majority of motorcycle riders stop riding their motorcycle at ages between 60 to 85 depending on how confident they feel, how capable they are, and the local laws.

Do you have to let a motorcycle warm up?

It is crucial that you let your motorcycle warm up before riding it as it will have a profound effect on the performance and safety. There are a lot of seals and rings inside the engine that require oil circulating at optimal temperature. Warming up a motorcycle allows that oil to circulate efficiently.