Review – BMC Speedfox 01

The Swiss bicycle manufacturer known as BMC prides itself on putting athletes on the top step of the podium, but don’t let that lead you to believe that BMC doesn’t know how to have fun off the racecourse. The Speedfox 01 diverges from BMC’s road and cross-country racing heritage with a more aggressive geometry geared towards trail riding. That, however, is not the most standout feature of BMC’s all-new trail machine. The Speedfox is designed with a unique integrated system deemed Trailsync, but more on that shortly. We invited BMC’s new machine into our test fleet to see if this blend of cross-country racer and trail shredder could hold up to our local testing grounds.


The Speedfox 01 is made for the rider who wants a bike capable of trail riding one weekend and burning laps on a racecourse the next. BMC optimized the Speedfox for different-size riders by offering 27.5-inch wheels on small- and medium-sized frames, while larger riders benefit from 29-inch wheels on size-medium frames and up. We opted for the slightly larger medium frame with 29-inch wheels as opposed to 27.5-inch wheels. BMC further tai- lors the Speedfox to riders by offering 130 millimeters of travel on frames with 27.5-inch wheels and 120 millimeters on 29er frames.


The Speedfox 01 features a carbon frame with a 68.3-degree head tube angle (67.5 degrees on 27.5-inch models), a long top tube and short chainstays. The cockpit features 760-millimeter- wide handlebars and a 55-millimeter stem, providing quick and nimble handling. The Speedfox has internal cable routing, Boost axle spacing and a PF92 bottom bracket.

BMC continued to use its APS (Advanced Pivot System) suspension platform but incorporated its new Trailsync technology, which simultaneously adjusts suspension damping and saddle position with a single handlebar-mounted remote lever. The Speedfox uses an integrated dropper post that varies in travel from 80 to 120 millimeters, depending on frame size. The Trailsync remote lever operates the dropper post first and then automatically adjusts the shock’s damping. When the saddle is in the up position, the shock is nearly locked out, giving riders an efficient pedaling platform. Once the saddle is dropped, it’s time to rally, and the shock is instantly opened up for a smooth and plush ride.


The heart of the Speedfox is its TrailSync technology; however, don’t let that distract you from its other top-notch components. BMC spec’d a SRAM XO1 Eagle drivetrain, DT Swiss XM 1501 wheels and a RockShox Pike RCT3 fork paired with a Fox Float DPS shock. The cockpit features a bar and stem from BMC and Guide Ultimate brakes from SRAM. Together, these components helped improve performance out on the trail. Our test rig had a wide range of gearing for steep climbs, tubeless-ready wheels wrapped in Maxxis rubber for excellent traction and plush suspension components for soaking up rough terrain.



Setting sag: The first step to take when adjusting sag on the Speedfox is to drop the saddle. We know that sounds irrelevant, but lowering the saddle operates the shock’s damper, placing it in the open setting. This allows riders to set sag without interference. BMC placed a sag indicator on the drive side of the upper rocker to make setting sag that much easier. We used the indicator while setting up our bike and found it landed us right at 30 percent. Up front, we adjusted our fork to 25-percent sag.

Moving out: Trailsync gave the Speedfox a unique feel out on the trails. The basic idea behind Trailsync is that when a rider’s dropper post is extended to its full height, the shock becomes locked out, making the bike more efficient for climbs or flat sections. Once that rider hits the top of the trails and drops his saddle height, the shock opens up, allowing him to rip down the trails. The biggest benefit to this system is that a rider can quickly, with one simple push of a lever, be ready to tackle descents or climbs. The system doesn’t, however, allow independent control over the dropper or shock. This was rarely a problem but seemed to be a disadvantage in the eyes of some of our testers.

Climbing: The Speedfox excels on climbs thanks to its lightweight feel and efficient APS suspension design. While heading uphill, our testers noticed the Speedfox felt much like a hardtail due to the suspension being nearly locked out. This was ideal for smooth fire roads and singletrack; however, technical climbs caused our rear tire to deflect off rocks instead of soaking them up. Out of the saddle, the Speedfox accelerates with ease.

Cornering: BMC designed the Speedfox with an agile geometry built to rail around corners thanks to its short chainstays, short stem and 760-millimeter handlebars. Our 29-inch wheels and Maxxis tires held traction well, and the 68.25-degree head tube angle helped balance high-speed stability with cornering performance. Whether you’re ripping trails or looking to knock seconds off your lap time, the Speedfox has the capability to do it.

Descending: The Speedfox may climb like a hardtail, but it sure doesn’t descend like one. Once the saddle is lowered and the shock is simultaneously switched to the open mode, the Speedfox transforms into a trail shredder. Our test riders would have liked to see a longer-travel dropper post aboard the Speedfox, as it could aid in descending performance; however, it didn’t seem to slow them down. BMC found a way to make the Speedfox have two completely different personalities with the flick of a switch. The Speedfox uses its plush suspension to its advantage, and its 29-inch wheels roll right over the tops of big rocks and roots.


Before trail testing our Speedfox, we experienced an issue with its integrated dropper post that prevented it from locking into position. We removed the multi-port cover on the seat tube, as well as another cover underneath the top tube. These large ports gave us easy access inside of the frame and allowed us to spot the problem. The lock-body pin that is designed to hold the dropper in position was jammed. BMC mailed us a new lock body, which only took about 15 to 20 minutes to install. This remedied the problem.


The Speedfox is designed with BMC’s unique Trailsync system, which riders will come to love or hate. On one hand, the Speedfox can switch personalities at the single push of a lever, making it a great tool for descending and climbing. The downside, however, is that a rider is limited to two settings. Anyone who enjoys the added traction of plush rear suspension while climbing may find this system limiting. Descending with the saddle up is harsh to say the least. That said, Trailsync prepares riders for climbing and descending faster than any other system we’ve tried. If the Speedfox and its Trailsync technology have sparked your curiosity, then we recommend heading down to your local BMC dealer to try one for yourself.


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$7500bike testBMC Speedfox 01full suspensionmountain bikingRacingTrailsync system