Buying a mountain bike used to be an easy task: They all came with 26-inch wheels and you could choose between buying a fully rigid bike, a bike with front suspension, or one with full suspension. But today’s mountain bikes — XCs, enduro bikes, all-mountain, or trail bikes — come in all shapes and wheel sizes, making it harder than ever to decide which one is best for you. And 2017 is quickly shaping up to be the year of the new 27.5+ (“27 plus”) tire size, which offers the same rolling diameter of a 29-inch tire, but in an extra-wide package that provides more traction and floats over obstacles and rough terrain. These 27.5+ or “mid-fat” bikes certainly could make life more complicated when it comes to buying a new bike, but thanks to SRAM’s new Boost standard for rear-axle spacing and drivetrains, companies can now build frames compatible with both 29-inch and 27.5+ tires — without sacrificing handling or drivetrain performance. Here, we've made it a little easier for you to find your next ride.