Is this a bad thing in a 2001 Kawasaki ER5 which usually has 91 Unleaded petrol? I wasn't concentrating and accidentally put some in my bike this week and now it's idling real low (ie around 1000 rpm) and blowing out blue (oil smelling) smoke on start up. When I eventually get it on the road it's fine, but low speed is a bit dodgy. My manual says any fuel above 91 is fine, but this doesn't sound or look good. Thanks in advance.