I try to turn mine off when I shut the engine down also, but every once in a while I will forget and leave it on for several days and have had no problems. But I am puzzled how the fuel could get in to the crankcase, if you left it on.
My petcock or fuel tap,is also a little hard hard to turn, if the bike has been sitting for a while. Sounds like the guy on the other site just likes to beat himself up
-PES
