should be towards the rear of the tank never known a bike to not have one some old bikes (Triumps) had 2 one either side turning the tap from vertical (I) to the horizontal (-) should turn off the fuel
WARNING
SHOULD NOT HAVE PETROL STORED IN A FLAT YOU ARE SITTING ON A TIME BOMB ALONG WITH THE OTHER TENANTS A SINGLE SPARK IS ALL IT TAKES (COOKER OR LIGHT SWITCH)TO KER -BOOOOOOM
wirecutterman, February 2008