Trek 27.5 Mountain Bikes
What is 27.5? 27.5 (aka 650B) is a common wheel size found on mountain bikes. The wheels (with tires mounted) measure about 27.5 inches in diameter. They were introduced as an in between alternative to traditional 26 and 29 inch wheels, and they blend the strengths of both sizes. For example, 27.5 wheels fit small riders better, accelerate quickly, and have a nimble feel similar to 26 inch wheels. They also feel more stable, roll faster, and improve traction similar to 29 inch wheels.
Who is it for? Trek suggests riders go with the fastest wheel size that fits. Usually, the bigger wheel is the faster wheel. Trek mountain bikes come with 27.5 inch wheels on small and extra small frame sizes, but 29 inch wheels on medium through extra large frames. If you're a shorter rider, it's worth visiting your local bike shop to take a spin on a 27.5 bike to see how it feels. But 27.5 isn't only for short riders. You'll also find these wheels spec'ed on Enduro, Downhill, and Dirt Jumper bikes because of their lively, maneuverable feel. If you spend a lot of time on the jumps at the Ogden Bike Park or have a need for DH speed, chances are some of the bikes on your wish list may roll with 27.5.