The petcock valve has a tube that sticks up inside the gas tank. When the valve is in the "on" position, it takes fuel through the top part of the tube. When the valve is in the "reserve" position, it takes fuel from the bottom of the tube. So if you have it in the "on" position, once the fuel gets down below the top of the tube, it will run out of fuel. Then, you turn the valve to the "reserve" position and finish running the fuel out of the tank. This is why it's important to turn the valve back to the "on" position after you refill the tank. If you don't it will run all the fuel out and you won't have any in the "reserve" position when you run out.
Most 4-wheeler problems are caused by a loose nut connecting the handlebars and the seat!!
You only need two tools in life -- WD-40 and duct tape. If it doesn't move and should, use the WD-40. If it shouldn't move and does, use the duct tape.
Last edited by Helmut; 05-19-2011 at 08:12 PM.