cleaning my new 1150gs the other day i noticed a small plastic cap on the underside of the air filter housing just above the rear shock preload adjuster . thinking this was a drain plug to let water out of the filter housing i undid it and it pissed oil over my new monoblock driveway which pleased the wife no end anyhoo , what is this ?? and is the oil normaly in there ??
It is the air filter drain plug, and if you overfill the engine oil (easily done) the engine breather pipe vents the excess oil into the air-box where the air filter is,and collects at the bottom.
