Bear in mind this is from a british perspective, having driven in the U.S. (now I always get the biggest SUV I can after the first time) I may ride differently there should the opportunity arise to do so.
Headless, like everything the answer to that question is dependent on the context. Police presence, blind entrances etc. To be honest the only time I would feel happy with my bike on the sidewalk is at a time of night and traffic/people density that would render the exercise pointless due to the traffic levels on the road.
My apologies to the other motorcyclists here, the following statements are in no way a reflection of their opinions or conduct on the road. They are mine and were expensively acquired, dropping a sportsbike, even at low speed, cost me on average £2000 to put right.
Lane splitting is down to personal choice and judgement. I've seen other riders do it in ways that have me braking to avoid the accident they are about to cause. On the other hand, I will admit that I am guilty of it myself. When I was commuting 70ish miles a day on mostly dual carraigeway I did it. I used my bikes superior accelleration to minimise the the time spent between vehicles and undertook as a matter of routine if the clearance available was greater than 1 1/2 times a car width and there were no junctions ahead etc., etc. I used my judgement and the only assumption I ever made about the behaviour of car drivers was that they could see me perfectly and were determined to kill me. Combine this with my expensive education, track and road based, the fact that I have no wish to join the choir invisibule and I seemed to get along alright. Only ever had to use my brakes once or twice doing it, the rest of the time engine braking sufficed due to good observation, adjustment to road conditions and planning.
Until you ride a motorcycle of reasonable power and handling you have no idea just how huge the difference is to a car. You have to adjust your entire outlook to it's capabilities. Ridden by a rider of skill even my little gsxr750 will out accellerate, out brake and out manouvre 95% of four wheeled traffic. It is my opinion that these capabilities, coupled with an awareness of the weak points of your bike and riding ability, allow you to progress to your destination in a manner that simply cannot be understood by someone who does not have experience in the field, Rendering their opinions mostly irrelavant due to a lack of a common frame of reference.
Let the flames commence, I haven't been this arrogant and dismissive of the opinions of others in ages
By the way I have experience in lots of fields, oil seed rape, wheat and cabbage to name but a few. Thats why I spent more on instruction and track time than bikes
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