In a world where cyclists didn’t spout the phrase “let’s get rad” whenever they hit a fun trail or road, the word ‘rad’ was short for radical (or radians, for those in a STEM state of mind). Radical represents complete change of a fundamental aspect of something, and really if you think that way, is your favorite section of trail truly ‘rad’?
Meet the all-new 2019 BMC Fourstroke 01 XC bike, with an industry-first Race Application Dropper (RAD) seatpost. For the first time in quite a while, a mountain bike can claim to be ‘rad’, technically speaking. This model is the 2019 BMC Fourstroke 01 ONE, the top-spec XC bike from BMC. It features a Fox Factory suspension with 100mm travel front and rear, DT Swiss XRC 1200 carbon fiber wheels, and SRAM XX1 Eagle drivetrain. Standard superbike fare.
Perhaps what makes the Fourstroke 01 so radically different from the competition is the Race Application Dropper, or RAD, seatpost. RAD integrates a two-position, 90mm dropper seatpost into the frameset, with the end result of improving stiffness by 30%, cutting weight by nearly 200 grams over an equivalent Fox Transfer 100mm dropper, and making the Fourstroke 01 even more race-ready than before. To do so, BMC uses a proprietary oval shape that’s inherently stronger than a typical circular post design, and uses as few parts as possible. Not only are there no hydraulic parts to speak of, and compared to mechanical droppers, the RAD operates at nearly 90% lower air pressures than the industry-standard Fox Transfer. Low pressures means less stress on seals, greater reliability, and less necessary maintenance. That alone is pretty cool.
BMC’s radicalism doesn’t stop at the conveniently-named dropper seatpost, but it continues in the bike’s geometry as well. Previous-generation Fourstroke models had wheelbase, angle, and front-center numbers that aren’t too far off from a modern gravel bike. This new model moves to a considerably more-progressive XC geometry for greater stability on descents. Combined with a longer front end, you’ll now find a 67.5° head tube angle that pairs to a 44mm-offset fork; together, the bike should be much more stable on descents than the twitchy previous generation. Additionally, a steep 75.5° seat tube angle with 429mm chainstays, and longer reach on every size puts riders in a more central position on the bike to improve weight distribution on rocky XC course descents.
Every gram counts in XC, and the new Fourstroke 01 uses fewer individual parts than before. A fully-integrated headset, a new carbon suspension pivot, a lighter one-piece carbon rear triangle, and improved internal cable routing make the bike much easier to maintain than before. All in, BMC reckons the Fourstroke 01 weighs just 2180 grams with a shock and hardware, and 2525 grams decked out with the RAD seatpost and hardware. Not ‘out of this world’ numbers, but including the dropper post the Fourstroke 01 is right there in weight beside the SCOTT Spark RC SL and 2019 Orbea Oiz OMR.
Like before, the Fourstroke 01 uses 29er wheels in all sizes. BMC’s Advanced Pivot System (APS) suspension, is back for another go as well. This multi-link suspension design offers superior bump compliance over a single pivot design. Similar to that found on the SCOTT Spark SL, the suspension curve ramps up a bit more than the Spark to provide a slightly firmer pedaling platform. BMC also saw fit to install improved frame protection in the form of molded plastic covers on the chainstay and lower link, and an integrated fork stopper for improved durability and a neat look.
APS is not single pivot, it’s a multi link, instant center design that offers superior bump compliance over a single pivot design. You can also tune the axle path more than with single pivot design. The disadvantage is single pivot is lighter. We chose to “add weight” to get the superior suspension design.
Radical doesn’t always mean good; it just means that there’s a substantial departure from the norm. With a number of fresh takes on XC mountain bike features and needs, BMC’s newest mountain bike doesn’t need to be truly ‘rad’ to be a top-grade bike. It does need to be a cohesive package that allows riders to focus on nothing but riding the trails, and the all-new Fourstroke 01 is a rad way of doing it.
Have any questions about the all-new 2019 BMC Fourstroke 01? Send us an email any time to firstname.lastname@example.org, or give us call during business hours.