Your Dad will love the suspension / ride far more than he will worry about any power issues. Most people I've talked to that switch over to the DS find the can ride all day long and not get sore when they used to get sore after an hour or two of riding.

Even if the power isn't enough for him he can pretty easily do some upgrades to increase the power. For him I would look to Ron Wood products through On Dunes. The Stage wo kit will give some amazing power gains. Not sure if I would suggest cams for him since he probably wants a pretty wide powerband.

 

thanx for all your responses, we were thinking that 4500 is a little steep too, but we know for a fact that this guy took great care of it, and he barely ever rode it, he got it to ride with his brother and barely broke it in before he stopped riding it, it only has a few hours on it, so it is like new