A Perfect Blend
Combining defensive tactics and aggressive riding will allow you to become a rider that can weather any storm. The secret is knowing when to use each of the tactics. After all, blasting aggressively down Yonge Street is an open invitation for trouble. Conversely, creeping slowly down the road invites different (but no less deadly) trouble, putting you at the mercy of other drivers' skills - or lack thereof.
Defensive riding means being aware of your space and maintaining that space by positioning yourself in surrounding traffic. Riding defensively is a way of looking at traffic to predict its effect on you, and doing your best to make sure that this effect is minimal.
Riding aggressively is an applied technique to be exercised only occasionally. As a motorcyclist, you must put yourself in view of other drivers, and sometimes that means a bit of aggressive throttle use to come up even with a driver's window. Simply put, sometimes slowing down is extremely dangerous and some aggressive acceleration or lane changing is required.
Trust No One
The most important rule of urban motorcycle riding is to trust no one but you. Strange as it may seem, paranoia is the key. If you see a dented, dirty or run-down car, be afraid. Dents indicate historical damage and demonstrate that the owner of the vehicle has not made an effort to repair the damage. Similarly, dirty vehicles indicate a disinterested owner, which may very well represent the driving habits of this person.
As you gain experience, you'll undoubtedly start to notice trends in particular types of vehicles. Drivers of minivans, for instance, are often dealing with screaming kids in the back seat. As a result, drivers of minivans may not have the ability to focus on the road at all times and should immediately trigger your paranoia. Similarly, sports cars are often driven by aggressive drivers who have the ability to accelerate quickly and change lanes often, so stay well back. Drivers of SUVs and large pickup trucks should also be added to your “watch” list, as they may be carrying a large amount of goods resulting in reduced visibility. In all, there are really no vehicles you can ignore while riding in an urban area. Trust no one but yourself.