This is a tough one. I doubt I would have survived a bike at 16. The temptation to go fast combined with that false sense of invulnerability would likely have just been too much. It was bad enough just with driving cars/trucks.
If you know for a fact he will be riding on the street, then I would suggest something like a Suzuki GS500 (without the fairings). I don't know how tall he is, but the seat height on these is relatively low, so not intimidating. These bikes will run highway speeds, but they are not rockets. They are inexpensive. The same is true for case guards, brake levers, and clutch levers. You can put a wind screen on them for very little money. You can even throw bags on them and tour if you want. Suspension is SOFT, so if he weighs very much, new springs and heavier fork oil might be in order, but that is cheap to do.
Buy used. The bike will get dropped and damaged. There's no point in eating that expense on a new bike. Buy naked and install guards where possible. That will minimize damage and cost, which can have a seriously negative impact on the experience for new riders!!
But really, the bike is not the main issue.
I would REALLY emphasize that taking and passing the MSF course basically qualifies you to ride around in a parking lot. To that end, I would strongly suggest sticking to big empty parking lots for a while to work on basic control skills like shifting coordination, starting and stopping, panic braking, turning, swerving, etc,... It is really best to get those things down at relatively low speeds in a predictable environment. Once you feel he's got those basics down and has created some muscle memory for operating the bike, THEN you take him out on some empty back roads so he can get used to higher speeds.
The idea is that you don't want the new rider to be concentrating on those basic control issues while at the same time trying to deal with all the stuff going on around him in traffic. A rider only has so much attention to spread among doing various tasks and monitoring and reacting to his environment. Speed only makes this worse until the new rider learns what can safely be ignored and what actually requires his attention. With experience, the rider learns to focus on what really matters. They learn to relax.
If you have the opportunity, I would take him on some rides. I would also use communicators so you can talk with him about what you are doing during the ride. I do this a LOT with my kids. We talk about the road conditions, what is around us, other vehicles, potential danger areas like intersections and parking lots, common threats to look for while riding, proper lines through a corner, when to brake, when to get back on the gas, how to lean the bike, and basically anything else I can think of that has to do with safely operating a bike under all kinds of conditions. They get used to the sensations of the bike, leaning, braking, accelerating, etc,... So that is not new to them when they are in control of their own bike. I also show them that you don't have to run at break neck speeds to have fun. They all ride dirt bikes as well, so they do get to put some of what they are learning to use. I even talk to them about this kind of stuff when we are driving. Ideally, when they finally get to the point where they are driving or riding on the street, a good foundation will have been laid.
When you ride with the new rider on the street, it is usually best to let the new rider lead. I will say that again, let the new rider lead! I know there are some that would say new riders should follow so they can observe the more experienced rider. That might be good for limited cases where you are trying to show them something specific. However, I have found that even when intending to ride slower, experienced riders will often tend to creep up to their normal "relaxed" pace without even realizing it. That pace is often FAR faster than the pace at which new riders might be comfortable. Not wanting to fall behind or disappoint experienced riders, new riders will often ride over their abilities. That rarely ends well and can scare new riders to the point that they either develop bad coping habits or just quit riding altogether. If the experienced riders follow, AND keep a good following distance so the new riders don't feel pushed, the new riders are better able to run a comfortable pace. I have seen this a LOT over the years and have seen too many riders get hurt as a result.
I also cannot stress strongly enough the importance of being able to communicate to a new rider. I have taught riders without communicators and with. There is NO comparison in the experiences. Being able to communicate while a new rider is in the middle of performing some skill or following instructions makes a HUGE difference in the experience for teacher and student alike. This is especially true where the teacher sees the student slipping into a panic. Being able to communicate calmly allows the teacher to refocus the student or to talk them through something. I have found this really nice while working with my kids on their dirt bikes. Trying to yell at them from a distance while they are freaking out just doesn't work.
New riders often worry a lot about being "fast". I stress the idea with new riders that they should not be focusing on being fast. Instead, they should focus on being smooth and relaxed. If they are scaring themselves by riding over their abilities in an attempt to be fast, they will get tense. If they are tense, they will not be smooth. If they are not smooth, they are likely upsetting the bike. This make them tense... and it just feeds back into the loop. If they focus on proper execution and smoothness, their skills will truly improve and they will become fast as a byproduct. If they push hard in an attempt to go fast, they will likely scare themselves badly a few times, which can create an artificial and sometimes permanent limit on their peak skill level. Listen to the top racers, on pavement or dirt, and they all talk about the importance of being smooth... "like butter!"
Good reading material:
- Keith Code: Twist of the Wrist Vol. II
The stuff about survival reactions versus proper reactions is invaluable. Also some great exercises for developing good visual skills. There is a Vol. I, and it is good, but it is more track oriented.
- David Hough:
Proficient Motorcycling: The Ultimate Guide to Riding Well
and,
Street Strategies: A Survival Guide for Motorcyclists
All of these are great bathroom books! They cover all manner of issues relating to controlling the bike and also common threats to riders and how to deal with them. I read them all, more than once. Rereading them every few years is not a bad idea even for experienced riders. There have been more than a few occasions where something in every one of those books saved me because it popped into my head when it was most needed!
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, I feel better about his being a responsible rider now that he has 8 years riding under his belt.
