I thought I'd bring this here to see what you guys and girls think or would do yourself. I have a Trek 2200 (aluminum frame) thats several years old. Right now while I'm in college, it's the road bike I have. I haven't let my brother ride it because he's not real good about not wrecking things like that, or paying for them once he does wreck them. I recently bought a trainer and now he wants on it too. He weighs around 200 pounds, I'm around 170. What I'm concerned about is all of that extra use might be more wear and tear on the bike than I want, but I haven't had a trainer for long so I don't know how "rough" it could possibly be for a bike on a trainer, I guess as rough as you make it (and my bro is not one to be gentle on things, especially if you're not standing over him). I definately don't want any hardcore cranking on it in the trainer as I feel with the bike unable to flex as much hooked onto the trainer that it would be harder on the frame, and I'm not sure that I can trust him not to do it when I'm not around. So am I being stingy, or am I justified?