What is the best mountain bike short out there? We tested several different shorts from the top brands in our Best Mountain Bike Short Review and discovered some important things you should consider before you buy a baggy short for mountain biking.
First, we considered what makes a mountain bike short (rather than a road bike short or just an athletic short). We define mountain bike shorts as non form-fitting baggy shorts which provide more protection and features than tight lycra-style road shorts. The thing that separated these shorts from other types of athletic shorts is a chamois pad attached to a form-fitting liner worn beneath the outer short and features tailored towards making biking more comfortable.
Style of Riding
When shopping for a new pair of mountain bike shorts, first consider what type of riding you will be doing the most. "Mountain Biking" is a broad term which covers everything from lycra clad cross-country racing to hucking huge drops at the Red Bull Rampage in full body armor. Most riders have a pretty good idea of what type of riding they prefer, which also dictates their bike selection. Here is a quick breakdown and some ideas of how the shorts we tested fits with each riding kit.
Pearl Izumi Canyon and Sugoi RSX are the best shorts for this type of riding. If you are a privateer racing cross-country you should probably consider a road-style lycra short since no baggy can match the range of motion and aerodynamics of these form fitting shorts. Check out our Road Bike Short Review for the best in this category. Inversely, if you simply can't stand form-fitting lycra, look for a lighter cross-country oriented short for road riding.
Enduro is the new hot word in mountain biking these days. While the definition of what enduro actually is may vary, it involves riding up as well as riding down technical terrain. Enduro somewhat takes the place of what used to be referred to as trail and all-mountain riding, and might be best summarized by calling it "do-it-all" mountain biking. Five and six inch travel full-suspension bikes fall into this category. Along with this new title for what most people have always just called "mountain biking" has come the return of the 27.5" or 650b wheel size which sits right between 29" and 26". Whether you are buying into this wheel size or not, you should look for shorts that balance protection with pedal ability and do-it-all features for this type of riding. Some shorts to consider would be the Zoic Ether, Dakine Boundary or our absolute favorite, the Troy Lee Ruckus all of which will work with kneepads whether you wear them just for the descent or all the time.
Shorts for downhill riding should be long and have large enough leg openings to fit over the tops of kneepads. Durability is also important for this style of riding since crashing in gnarly terrain is more common. Of the shorts we tested, the Troy Lee Ruckus is best suited for this type of riding since it has a long inseam length and large leg openings to accommodate knee pads while the stretch fabric is both durable and protective. For full blown bike park downhill riding where you spend much more time out of the saddle than in it, you may want a heavier downhill specific short that does not have a liner short or chamois. While we did not include these shorts in our tests, we think that the Troy Lee Moto and Dakine Descent are excellent options for pure downhill.
All of the pads we tested are made of foam except for the one found on the Canari Cyclewear Canyon II which is made from a micro-encapsulated silicone gel. A well-articulated shape that matches the shape of the body in a seated position is the first thing we look for in a chamois. We also prefer chamois with dense padding, multiple thickness zones, and a smooth, seam-free cover made from wicking synthetic material. It is important that the chamois is positioned correctly by the short to be between the rider and the saddle when in the seated position. Mountain bikers typically pedal in a more upright position than road bikers. The contact between rider and saddle is more posterior because of the more upright position, and the chamois of a good mountain short should also be sewn into the short slightly more towards the rear of the short.
Mountain bike shorts are available with a variety of added features. Again, we recommend that you first consider what type of riding you are going to do most often and what type of features you need for that type of riding. We recommend buying a short with features you will use and nothing more. Unused bells and whistles are likely to just get in the way and increase the cost of a short.
For cross-country and enduro riders who always wear a hydration pack, shorts with pockets may not be necessary. However most downhill riders riding the bike park usually forgo the pack and will want a short with a least a few zippered pockets to secure a bike tool and whatever device they are using to upload their Strava times. Regardless of what type of riding you are doing, we recommend pockets that securely close with a zipper rather than velcro or nothing at all. We don't recommend carrying anything more valuable than a gu in a non-zippered pocket when mountain biking since items are likely to bounce out unnoticed as you scream through a rock garden.
Just like any piece of clothing, getting the right size is as important as any other attribute. We tested all of the shorts in a size medium or 32" inseam, depending on how they were labeled by the manufacturer. The lone exception to this was the Sugoi RSX, which we tested in large. The shorts that we felt ran true to this size were the Fox Ranger, Zoic Ether, Canari Canyon Gel, Sugoi RSX and Troy Lee Ruckus. The shorts that ran slightly small were the Pearl Izumi Canyon and Dakine Boundary. We recommend sizing these up if you like more room or are on the upper end of the sizing chart. The Endura Hummvee ran extremely small and we recommend sizing that short up at least one size. None of the shorts we tested ran large for the size.