I bought a 2005 Kona Dawg mountain bike recently, think I might have overbought for what riding I do, wife and I mostly ride local bike paths, some coastal trails along the ocean when trailer camping there, but no heavy duty offroad, I love the looks of the Dawg but it seems sluggish and heavy on the trails we ride, wife wants me to upgrade the tires from knobbies to Serfas Drifters for better rolling resistance, but I think I may need to reconsider going back to a light weight quality hardtail, any suggestions, I am leaning towards something like a Motobecane fantom Pro Ti. or??