If you dont mind gettin screwed let him ride it,I will never let anyone ride my **** until I got cash in hand and their licence,and car keys,if they are serious they will do what you ask.My friend wrecked a dudes bike cause the dumb *** seller put armor all on the tires,WTF.My boy gave him some cash to fix some of it, just cause he felt kinda bad,most people will just say **** off and leave,dont chance it or you'll regret it.