interesting thoughts here. It's really tough to let somebody else ride your bike, whether you are selling or they just want to go for a ride.
I have bought and sold many bikes. I've bought them after test riding and without test riding. I've also sold them with and without test rides.
What i do is first size the person up. If they show up with a motorcycle then that is a big plus. When i am the buyer, i nearly always show up on a motorcycle to look at motorcycles. If they show up with gear that is well used, that's a big plus. Older is a plus. If they are nervous about letting me ride, then i have them ride the bike while i ride my bike. That usually makes folks fee much better.
After that, i generally will go with them on a ride. Me on a bike, them on the one they are considering for purchase. That's hard to do if your only bike is the one that you are selling ... But seriously now ... Who would sell their only bike :confused2: I'm kidding, if you are in a tough spot, then so be it.
If they don't have a bike and they don't have obviously well used gear then i get a bit nervous. Like the guy who asks, "do you have a helmet that i can use?" uhh .... You didn't bring your helmet? Hmmmm ... In that situation, then i start asking things like, how long have you been riding ... Will this be your first bike, etc.
I sold a 650 savage to a young girl a few years ago who had never ridden. I asked that she please bring somebody with her who could test drive the bike for her. She did and it worked out just great.
Ok, so that was a rambling answer. I'd be careful to demand cash up front. I've walked away from bikes when folks have done that to me. But at the same time, definitely cya. Just don't assume that all buyers are the same. If the buyer knows how to ride a bike, then i suggest letting him ride it. If you have concerns about their ability, then certainly do not allow them to ride it.
Also, if a non-experienced rider showed up looking at a vmax, i would frankly tell them to look at a more mellow bike. I don't think this is a learners bike. Neither is my rocket. Neither are most bullet bikes.
Ugh ... I kept rambling!