I’m not your grandmother, but if I were, I wouldn’t want you to buy a motorcycle either. Not only are mortality rates an issue, but also severe injury.
We had a neighbor who lost both of her legs because of a motorcycle accident. She was a teenager.
I always wanted to buy a motorcycle but my parents - especially my father - said, “NO!” When I was 21 my father died suddenly and tragically, so 2 years later, since I no longer had my father to prohibit it, I went into a motorcycle shop to buy a Kawasaki 750. I put $50 down and was going to pick up the bike the following week. I could literally hear my father’s voice from the grave telling me how stupid I will feel if I kill myself on this motorcycle, and I never returned to the shop to even attempt to get a refund on my deposit.
However… at an older age, when I lived in Japan I did purchase a 90cc scooter and drove all over congested Tokyo, sometimes with my wife on the back.
re: “How would you think I should go about setting this sort of concern at ease?”
sorry, but I don’t think you can. she loves you too much 
Without trying to sound like the kid’s mother in “A Christmas Story” (“you’ll shoot your eye out”), I kind of agree with other users about commuting on a motorcycle to school like that on heavily travelled roads and freeways. The problem as many have said is not necessarily that you will be some idiot driving crazily, but rather it is other drivers on the road that you have to be worried about. Many of them simply don’t see motorcyclists, and with a bike there just is little protection if something does happen. And magnify the risk if driving at night, or in bad weather like fog and rain, or in the fall when leaves drop on the road.
A bike seems to be cheap transportation, they can get a lot of MPG, and are easier to park, but there is also the concept of risk based costs, too, that you aren’t factoring in. I don’t know how much motorcycle insurance is versus car insurance, but one of the things you have to think of is the potential cost if you do get seriously injured, of medical costs that may not be covered by insurance, or not being mobile and so forth. Maybe it would be better to get a small, fuel efficient car and drive to a park and ride lot and take mass transit into SF,you could probably get an older car in decent shape for not much more than you would pay for a decent bike, and be able to drive that to a park and ride.
If you are dead set on getting a bike, and you want to try and make your grandmother feel better about it, then I would encourage you to take some motorcycle defensive driving classes (not the BS classroom course they offer to help you get rid of points on your license, I am talking classes where they teach you skills, for example, in how to lay down the bike if need be in case of an imminent crash, or how to control the bike in bad road situations and so forth. Those classes won’t make riding your bike as safe as driving a car (yes, driving a car has risks, but the risk of driving a car is statistically many orders of magnitude less than a motorcycle), but it does reduce risks more than a bit and may make her feel better.
When I drive, the scariest thing for me is seeing the motorcycles “splitting lanes”. It’s why when there’s traffic, I always stay in the fast lane, because that way I only have to worry about them on one side of my car.
Seriously, look for a cheap sublet near campus, or deal with public transit/uber/zipcar. Think of your poor worried grandmother who loves you.
Another in the NO, don’t do it camp. My step-dad wound up with his leg amputated just below the knee bc of a SF motor cycle accident many years ago.
I would consider utilizing all means at my disposal to keep my kids from riding on-road motorcycles. Off road isn’t great, but at least trees don’t move. And if you do purchase one, PLEASE don’t drink or do drugs and then ride.
I’m not winning any debate in favor of buying a motorcycle here, am I?
@musicprnt I’m much more invested in not owning a car than I am in buying a bike. It’s very hard to articulately convey just how much I don’t like driving cars. Also, I don’t have a license to drive cars, just motorcycles and mopeds. I’d have to shell out quite a bit of money on lessons and fees to get a license to drive cars.
@1214mom I don’t even get on my bicycle after I’ve had one beer.
I’m wondering if it might make her feel easier if I do buy a Vespa and accept that freeways aren’t really an option. I mean, I do really like the classic Vespa styling, and they are cheaper to own, insure, and gas up than motorcycles or cars.
“@musicprnt I’m much more invested in not owning a car than I am in buying a bike. It’s very hard to articulately convey just how much I despise driving cars.”
Then why not organize your life so you don’t have to drive? Many people live only with public transportation in CA. Why not find a way to go to school near where you live, or live near where you go to school? If not driving a car is that important to you, you could find a way (that won’t kill you).
I currently do live right next to schhol and take public transit. My problem is that I might not be able to afford to stay in San Francisco. If I could, I could avoid buying a vehicle at all, but I don’t know if I can really afford this city after May.
I know it’s crazy expensive, but it seems there is always a way. My son stayed in a hacker house for awhile, $800 a month. Shared room, but the price was right. There is certainly a cost with purchasing a motorcycle or a car, add on the gas, the insurance, and the time to commute. Or living somewhere that is right off the Bart line, if that goes near your school, might be a good option. Bart is amazing.
I’m with Gramma, too.
@busdriver11: What’s a hacker house?
OP, you should talk yourself out of this idea that you hate driving cars.
You have me at your side, Spaceship. I agree a Vespa is a nice ride and is pretty mainstream for college students. If you wear a helmet and drive just short of the speed limit, then you’ll have no problems.
OP, that is a statement that may not even be true. You can try to reduce your risk by staying off the highways, but exposed, whether on a motorcycle or a Vespa, is exposed. You cannot control what other drivers do, and they are typically operating a vehicle that weighs between one and two tons, on average. You and your Vespa are no match, no match at all.
@stugace I don’t know that driving anything in San Francisco is possible without problems, but mopeds sure are popular here, at least.
Speaking of wearing a helmet, any opinion on models? I kind of want something like a Bell 500, but I’m not terribly knowledgeable.
@Nrdsb4 I’m an urban bicyclist from San Jose. Not being a match for surrounding traffic on busy roads is quite normal to me. If anything, even a Vespa is larger and faster than my bicycle.
I know nothing about motorcycles, other than they’re cool-looking. However, I did look up the Bell 500 and… well… it looks “soft”, if you catch my drift.
That’s pretty irrelevant to my point.
@stugace Well, I’ll admit I’d use it on a moped but maybe not a motorcycle.
@Nrdsb4 As a bicyclist, higher speeds and larger bikes tend to be safer if the surrounding traffic is fast moving. A straight expressway with a bike lane is pretty comfortable riding (an expressway with just a shoulder is terrifying). It’s areas with a lot of curb cuts or right turns without lead intervals where I really start worrying. That’s where you’re gonna get smacked. I was extrapolating that into a moped. Bigger, faster, and more conspicuous than what I’m used to, especially with greater freedom of lane positioning.
Okay, but a bigger, faster bike or moped isn’t going to mean diddly if you get hit by a car. You’re just as exposed as you are on a smaller, slower one.