Tire sizes are starting to resemble algebra equations: 26 x 4.8, 27.5 x 2.6, 27.5+ x 3.25, 29 x 2.4, 29+ x 3.0.
But the numbers all add up the same鈥攚ider equals better. From a little extra girth on 鈥渘ormal鈥� tires to the monster-truck treads of fat bikes, bigger tires are becoming the norm for their superior grip and comfort. 鈥淏y increasing tire size, you increase the amount of rubber contacting the ground,鈥� says Chris 颅Cocalis, owner of . 鈥淭hat extra traction gives you confidence.鈥�
There are drawbacks to a聽bigger tire, in the form of increased weight and rolling resistance. Finding a happy medium spawned the plus-size trend; three-inch tires on 27.5-inch rims are an optimal compromise between heft and grip.
Pivot Switchblade
That search for an ideal traction-to-weight balance made the ($9,500 as tested; 28.9 lbs.) our favorite. It鈥檚 already an aggressive trail bike, with 135 millimeters of rear travel and a stout 150-millimeter Fox 36 fork, but聽the 2.8-inch聽Maxxis聽Rekon聽tires on this carbon stunner turned the nastiest trails into an easygoing cruise.
Part of the Switchblade鈥檚 success comes from tricks like extra-wide rear hub spacing, which allows for extremely short聽chainstays聽and the resulting poppy handling that鈥檚 rare in such an assertive bike. Then there鈥檚 the hulking 815-millimeter-wide bars, which made steering through rock gardens a snap. The Switchblade also accommodates 29-inch wheels fitted with 2.5-inch rubber, an arrangement that aggressive testers preferred for the added agility and cornering. With all options included, it鈥檚 the best-riding, most versatile mountain bike money can buy.
Three Other Standouts
- The ($4,700 and up; 28.4 lbs.) is one of the most aggressive 29ers on the market, with 150 millimeters of rear travel and a聽banger 160-millimeter fork.
- Though the ($4,700; 27.4 lbs.) is a plus-size model, it puts three inches of rubber on 29-inch hoops for outrageous technical capabilities, making it the only hardtail that can keep up with a full-suspension bike.
- With a pedaling stance as narrow as most standard mountain bikes, the ($3,200 and up;聽24.6 lbs.) pulled double duty聽on snow and summer trails.