I would first try to just put some thinner, slick tires on the bikes you have. Lock out the suspension and just make sure you are in low gears to spin up those hills. I live in a very hilly area in MD and have the trek Utopia which is comparable to the roam. I also have a road bike that is under 18 pounds. It really is all about fitness and not the bike. I easily glided up hills yesterday morning on my utopia that last year killed me on my road bike. But I have been riding way more this year and my utopia has lower gearing that I used instead of trying to power my way up at the expense of my knees.