Hey Markus, a few tips about Canada.
First, the Canadians are now starting to require a special insurance certificate to drive a motorcycle in Canada. Check with you insurance carrier, and they should be able to give you one.
As far as crossing the border, you currently only need positve US ID and a birth Certificate. It sounds like you have a passport, so you are good to go. The passport requirement goes into effect Summer of 2009.
If you decide to cross over in Detroit, they will not let you take the tunnel under the Detroit River. You must take the Ambassador Bridge which is where I-96 ends in Michigan. DO NOT STOP IN DETROIT FOR GAS! The bad guys will see your out of state plate and rob you at the pump... Either fill up in the US in the suburbs, or fill up in Windsor ON.
Lastly, I have made the trip you are speaking about a number of times. I would cross in Detroit and follow the 401 (QEW) past Toronto and up. Once you are past Toronto, the traffic really drops off.
Best of luck!
Pete (Williamston Michigan)
2003 K12RS/GT Options
1995 525i 5spd