Guess I have a take on this. 1st no one throws a leg over my bike until,I am sure they can handle it. 2nd how far am I from home? 3rd why do they want to ride my bike? The Iron Mistress is only a bit of steel and some other parts that make a bike into a thing some of us can't live without. I weigh the risk, make the call, and stand ready to deal with what ever happens.
I have let other people ride my bike, at home, and even at rallies far from home. Its my bike, I make the call, Yes or No, I have high standards. They increase with distance.
I have had friends jump on other bikes I have owned,without my permission, and go crash. I paid fines for allowing unauthorised operation of a vehicle because I refused to press charges for grand theft auto. I had a wrecked bike and a fine 100mi from home. I keep the key now.
My bike, My friend, My choice, Choose wisely Grass Hopper, I have paid the price for a decision I never got to make. Take the key!!!. If you make the call to let another ride your bike, Be a man about it, it's your bike, you made the call, deal with it. None of this, my best friend wrecked my bike, and won't cough up the money to fix it /bS/. If he didn't steal it, You didn't press charges, It's all on you. A hand shake is only worth the hand that you are shaking. Your call. Even if you shook hands. It boils down to being a real Texan, deal straight, never shake the hand of a man you don't trust, and if it goes bad warn others, but take the loss, and grow.