Insurance: Mine costs about $200/year in L.A.
Tires: I get about 20,000 to 30,000 miles on the Bridgestone radials. Some people have to replace their chains and tires much more frequently, but this is a matter of riding style.
Carrying stuff: I have a small (about 9") rack on the back of the bike. It’s amazing what you can carry with a small rack and a couple of bungees. The seat is big enough for two people, so large loads can be carried part on the seat and part on the rack. Combined with a backpack, I can carry all of the groceries I need. Large items such as paper towels or toilet paper can be strapped to the rack. Some people use tank bags. These are soft packs that sit atop the fuel tank. You don’t need a “dresser” or a “cruiser” to carry a nice load.
Mileage: Most of the 60-plus-thousand miles I have on this bike are freeway miles. I get over 50mpg in L.A. traffic.
Getting around: In California, it’s legal to share lanes (i.e., ride between lanes of cars when the traffic is slow). Also, motorcycles are allowed in carpool lanes (I think this is so in most states).
Parking: It’s easy to park a motorcycle almost anywhere. Motorcycles often park free (e.g., at LAX).
Fun: A commute is much more fun when you’re on a bike. Motorcycles have a nice power-to-weight ratio and there’s nothing like rolling open the throttle and getting immediate speed. Sometimes I like to swerve in a clear lane just for the fun of it. Note that I’m talking about a 600cc “standard” class bike here; not a “sportbike”. As modest as it is, it’s still capable of zooming along (at the cost of increased fuel consumption) at 120mph. (I did get a high-speed shimmy at 125 though.)
Okay, what about the downside?
Weather: Motorcycles are not suited to year-round riding in many parts of the country. A rainsuit and warm clothing extends the riding season for many places. I would not like to take a bike out on snow, but rain is easy to deal with if you’re a careful rider. Wearing leather in the rain results in a heavy, dripping, rain-soaked garment. Even if you’ve put water repellent on it, it will get wet.
Safety: If you crash on a bike, you’re much more likely to be injured or killed than if you’re in a car. Since you have only two wheels, a slick spot might send you down where a car will stay upright. (I once ran over a flattened aluminum can in a turn and the rear wheel slid out from under me.) Car drivers do not pay attention to motorcycles. They say “we came out of nowhere”, but the reality is that their scan is not as thorough or as frequent as it should be. You can mitigate drivers’ inattention by being especially aware of your surroundings and of what other drivers are doing. If you ride with the idea that everyone else is a moron and you take steps to avoid them and situations that put you into close proximity to them, you will be much safer.
Maintenance: Some people ride and ride and don’t do much maintenance. Other people get regular oil changes, lubes, chain tightening, tune ups, etc. Motorcycles do require more maintenance than cars but they’ll put up with a surprising amount of their owner’s abuse. But an ill-maintained bike will lose performance much sooner aand more frequently than an ill-maintained car. Also, bad maintenance on a motorcycle is much more a safety issue than it usually is with cars.
Scooters: Some people love them. But I personally don’t like their lack of power and their high centre of gravity. Great mileage though, and they seem simpler than a real motorcycle.
Cars can be very useful. If you have a great deal of groceries to carry, a car may be a better option. If you wear a suit, a car is better. (There are riding suits that fit over your clothes though.) You can’t eat your Big Mac or talk on the cell phone when you’re on a bike. (But I think that you should pay attention to driving when you’re on the road anyway.) If you’re worried about how your hair looks, you’ll have to deal with “helmet head”. Your date or SO might not be keen on the idea of riding on a bike. (I don’t like to ride on the back of a bike. I’d rather be doing the driving.) In California, it’s illegal to have earphones on both ears when you’re on a bike. No listening to the stereo. On the other hand, you can work on your “shower voice”.
You can get a small, economical car (or a big one, for that matter) and use it as your secondary vehicle. I rode my bike all the time until I bought a Porsche. I sold the 911 and bought a Jeep Cherokee. I tend to drive it more than I ride the bike out of sheer laziness. But in the Jeep I have to drive very conservatively (65mph or less) to get 20mpg. I can do 70 or more on the bike and get over 50mpg. My parking situation is that one or the other of the vehicles must be blocked into the parking space. That means I have to play “musical rides” if I want to switch. As I said, I’m just being lazy.
FWIW, I got my first mini-bike when I was six. My first real motorcyle was a new 1973 Yamaha 100 Enduro I got for my 12th birthday (after I’d been riding dad’s '64 Yamaha 80 for a couple of years). That was followed by a 1976 Yamaha 250 Enduro I got in 1977, a well-used 1979 Honda CX-500, and the Yamaha Seca II I got new in 1994. I think the dirt riding I did when I was a kid taught me how to anticipate situations and makes me a better rider on the road.
Motorcycles are unbelievably useful machines. Given their many advantages, it boggles the mind that more people don’t ride. Go out and get a bike. Learn how to ride. (Really learn!) But keep a car on-hand just in case.