Boasting a full-suspension, extra-strong aluminum frame, the GMC Topkick mountain bike is an ideal choice for both trail riding and rough city riding. The frame employs a floating beam suspension design mated to a Zoom suspension fork with elastomer/spring technology. This gives the bike a smooth, steady performance even on rough terrain. The Topkick's drivetrain, meanwhile, is outfitted with Microshift push shifters that control Shimano's tried-and-true TZ-30GS derailleur. The drivetrain also offers a strong aluminum wheel set with a V-shape rim profile and high-flange alloy hubs. And to keep you stopping smoothly in any circumstance, the Topkick boasts front and rear Promax disc brakes. Disc brakes are vastly superior to rim brakes, especially under adverse road conditions. True to its GMC roots, the Topkick mountain bike is rugged, good looking, and built for the long haul.