For years, wheel measurement wasn’t one thing most mountain bikers thought-about when purchasing for a motorcycle. That’s as a result of all mountain bikes got here with normal 26 in. wheels.
Then, alongside got here two wheel sizes which have, for probably the most half, overtaken 26 in. wheels. First on the scene have been 29 in. wheels (29ers), adopted just a few years later by 27.5 in. (also called 650b) wheels.
The precise measurement for you largely is determined by what you’re seeking to get from a mountain bike and the kind of terrain you prefer to journey.
At-a-glance comparability of 27.5” vs. 29er mountain bikes:
Favors shorter riders
Favors taller riders
Take check rides: As you think about 27.5 and 29 in. wheels, take into account that one of the simplest ways to study the variations is to really feel them for your self. Swing by your native REI or bike store and take each for a check journey.
Store 27.5 Mountain Bikes
Store 29er Mountain Bikes
27.5 in. wheels have sooner acceleration whereas 29ers are extra environment friendly on longer rides.
Smaller wheels speed up sooner than bigger wheels. That is due largely to the place the burden of the wheel is distributed. Bigger wheels place the burden of the spokes, rims, tubes and tires farther from the middle of the wheel, leading to greater rotational mass and slower acceleration. Whenever you reduce down on the rotational mass of a rolling object it’s going to roll sooner and with extra ease.
27.5”: Sooner acceleration is commonly cited as one of many greatest advantages of a 27.5” wheel when in comparison with a 29” wheel. Wheels that speed up sooner give a motorcycle a handy guide a rough, responsive really feel that many riders want.
29”: Wheels that speed up slower take longer to rise up to hurry, presumably giving the bike an unresponsive really feel. Nevertheless, as soon as the bigger wheels attain high pace, they’re truly extra environment friendly for longer rides than smaller wheels as a result of they require much less effort to maintain their momentum going.
Due to their better floor space (aka “contact patch”), 29 in. wheels have higher traction (when evaluating comparable tires).
27.5 in.: These wheels present superb traction and are good for many functions. Different issues, comparable to acceleration, weight and match might finally be extra essential components in your alternative of wheel measurement.
29 in.: These wheels, with their bigger contact patch, could also be your most suitable option if grip on slippery rocks and roots is a high precedence.
29ers roll over objects extra simply.
Assault angle is the angle fashioned when the spherical wheel touches a sq. object. A shallower angle is best as a result of the wheel can roll extra simply over the article.
27.5 in. wheels don’t roll over objects as simply as 29ers, however they’re nonetheless very succesful. Take into consideration the place you’ll be driving: when you’ll largely journey clean trails, 27. 5 in. wheels will serve you simply wonderful.
29 in. wheels have a barely shallower assault angle than 27.5 in. wheels, making them higher at rolling up and over any logs, roots and rocks that you just’ll encounter on the path. Many riders really feel extra assured with bigger wheels.
27.5 in. wheels are lighter.
There’s no approach round it; a bigger wheel is heavier. Bikes with 29 in. wheels can weigh about 2 lbs. greater than bikes with 27.5 in. wheels resulting from extra wheel materials and extra tire rubber.
Relying on the kind of driving you do, the burden of your bike might or might not be essential.
For those who’re an off-the-cuff rider: The load distinction between 27.5 in. wheels and 29 in. wheels might not be your greatest concern. You would possibly care extra about traction and assault angle.
For those who’re aggressive or go on long-distance cross-country rides: You’ll most likely be searching for methods to save lots of weight. Going with a smaller wheel is one solution to cut back weight, however it’s not the one approach. You can even look into ultralight carbon fiber frames, handlebars, seatposts and rims.
Setting your wheels as much as be tubeless is one other nice solution to cut back weight. Tubeless wheels not solely cut back general bike weight, however additionally they speed up sooner due to lowered rotational mass and so they have the additional benefit of with the ability to run at decrease tire strain for higher traction.
Maneuverability (Body Flex)
27.5 in. bikes are extra maneuverable.
A 29 in. bike is extra versatile because of the elongation of the body that comes with the bigger wheel measurement. This can lead to a motorcycle that feels more durable to deal with in tight turns.
For those who usually journey tight, twisty trails, you would possibly want the texture of a 27.5 in. bike. 27.5 in. wheels retain numerous the snappy really feel of the unique 26 in. measurement, whereas sustaining most of the advantages that include a bigger wheel.
29ers roll over obstacles extra simply, so it’s possible you’ll discover you don’t miss the snappy really feel of smaller wheels, as you’re in a position to go up and over rocks and roots quite than making an attempt to rapidly maneuver round them.
29ers are sometimes higher suited to taller riders.
The bigger 29 in. wheels have an effect on the general geometry of a motorcycle body extra drastically than 27.5 in. wheels. This could make it tough for shorter riders (particularly these shorter than 5 ft. 6 in.) to discover a 29er that matches effectively. Check journey each wheel sizes when you can.
Taller riders, particularly these over 6 ft. tall, might want the texture of a motorcycle with 29 in. wheels. Nevertheless, a motorcycle with 27.5 in. wheels may match tall riders effectively, so resolve the place your priorities are associated to acceleration, traction, assault angle and weight first.