Please forgive my ignorance - I am new to this! A good friend who is a motorbike enthusiast suggested we should always put premium/98 octane fuel in the motorbike and where possible, always purchased from BP as it is the best quality. We have had reason this past week to be at the repair shop with the scooter for a fuel pump issue. The mechanic in there suggested to use 91 Octane and also suggested BP or Shell fuel is best to use. His reason was that the higher octane fuels are notorious for clogging up the fuel pumps of scooters and motorbikes alike. Our internet searches on this don't really suggest strongly one way or another. The girl in me tends to want to go with what the 'professional' mechanic says. But then I also have trust in my friend as he hasn't led us astray yet... So, what fuel do you use and why? We have a Honda CB400 if it makes any difference.