[ossiblue]

If a child, visiting your home, is injured, your homeowners policy will typically cover medical costs and defend you if a lawsuit develops. In your proposal, since you are not home, that protection would not likely be available. In either case, you can always be sued for negligence--something that cannot be eliminated by a parental waiver. Best intentions and friendships can go south very quickly when personal injuries happen, especially to a child. Your friend may have no intention whatsoever to sue, but if his child is severely injured and medical expenses are high, he may have no choice.

I agree, it's a bad choice. Best bet is to have the father join in on a group ride.