Procedures for Checking the Motor Oil in a 2001 Yamaha YZ250Fby Chris Gilliland
While most motorcycles store their oil supply within their motors or in a separate oil tank, Yamaha YZ250F dirt bikes keep their oil within their frames. This unusual arrangement can cause a fair amount of confusion for a new FZ250F owner since the oil dipstick is located behind the handlebars and the steering yoke as opposed to being found on the side of the motor.
Preparing the Motorcycle
The YZ250F needs a small amount of preparation before the oil can be checked, mostly in the form of warming up the oil supply. The density of the motor oil is affected by temperature, meaning that the oil expands as it is warmed up, providing an accurate indication of the oil level within the frame. Start the dirt bike and let it idle in place for two to three minutes before shutting it down. The motorcycle must be held in a level, upright position for the duration of the oil check, so have an assistant support it or place a piece of wood under its side stand.
Checking the Oil Level
Unscrew the oil dipstick from the motorcycle's frame, positioned just in front of the fuel tank, and withdraw it completely. Clean off any oil from the dipstick with a clean shop rag before reinserting it into the frame. You do not need to screw the dipstick into place; just insert it until the threaded portion of the dipstick touches the frame. Withdraw the dipstick again and take a look at the oil marks left on its tip. A pair of lines on the top and bottom of the dipstick's tip indicates the frame's maximum and minimum oil capacity. For best results, the oil level should rest at or near the midway point between both marks. Reinsert the dipstick and screw it into place if the oil level is within this range.
Adjusting the Oil Level
The oil tank should be refilled immediately if the oil level is near the dipstick's bottom mark. A funnel placed into the frame's oil filler neck will prevent oil spills onto the motorcycle. Pour a small amount of 10W30 motor oil into the frame and check the oil level with the dipstick again. Continue until the oil level is centered between both marks on the dipstick. Alternatively, excess oil can be siphoned out of the frame using a hand pump. An over-filled oil tank can create transmission difficulties and cause the excess oil to be ejected from the crankcase and into the air filter.
- "The Professional Motorcycle Repair Program"; Professional Career Development Institute; 1995
- "Yamaha YZ250F(N) Owner's Service Manual"; Yamaha Motor Corp.; 2001
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