Racebike concept comparison
End of a purist idea?

Featherweight forks boasting 120mm of travel and World Cup racers rocking dropper posts pose a pressing query: Are race rigs with 100mm of travel still relevant? We’ve not only put various bikes to the test, but we’ve also modded one to pinpoint the nuances between these design philosophies.

Progress obliterates. Case in point: high-quality 26-inch bikes are no more. The signs proclaiming „29ers suck!“ that were seen at the courses of Downhill World Cups for years have not followed through. The old wheel standard has vanished into obscurity. And any die-hard rider who expressed their early-millennium lifestyle with a 3-ring crankset tattoo now has to explain to their kids the significance of those seemingly excessive chainrings on dad’s calf.

The MTB industry’s giant waves of progress are undoubtedly behind us, yet the combo of marketing and engineering might just forcefully show us its will. Dear 100 millimeter race rigs, be warned. The enemy is lurking, and it’s armed with a relentless drive for change.

With the onslaught of marketing campaigns pushing new products and trends, it’s completely understandable that many riders approach each emerging trend with a healthy dose of skepticism. Why would the tried-and-true 100mm of fork travel suddenly not cut it? After all, World Cup races are still being clinched on quintessential 100mm race bikes. Moreover, the Alps can definitely still be conquered on a minimalist 100mm bike. Yet, the winds of change are unmistakable.

Last year, Nino Schurter clinched the 2022 World Championship and the overall 2023 World Cup title aboard a rig with 120mm of travel. The Cape Epic 2022 was also conquered with a plush 120mm of rear suspension. Off the race track, an increasing number of manufacturers are phasing out their 100mm travel bikes from their line-ups. Mondraker, Scott, and Orbea have all dropped the classic XC full-suspension models. Rose is even putting 120mm of travel into its latest racing hardtail and equips the PDQ exclusively with a dropper post.

Ever since we started our work at bike-test.com, we’ve emphasised that 100mm travel race bikes with a rigid post have a very narrow range of application. Models like the Scott Scale RC, the Rockrider Race 740, or the Cervelo ZFS 5 absolutely shred within their limits on descents. However, the Rose PDQ made it clear at its unveiling this summer, just how tight the boundaries of the classic XC rig truly are. And the Canyon Lux Trail solidified that sentiment in our most recent ride session.

With an additional 20 millimeters of travel and a dropper post, both the PDQ and the Lux Trail open up serious singletrack to riders who aren’t as versed. When we last put the Merida Big.Nine to the test – a rig with a classic cross-country (CC) setup – we were keen to dig deeper. We wondered, what are the trade-offs when you commit to extra suspension travel and the versatility of a telescopic seatpost.

We promptly converted the Merida Big.Nine 10 K for a reason. Why this bike? The Big.Nine captured our interest with its weight of 9.4 kilograms, but tests also clearly showed that it quickly reaches its limits off-road. Moreover, this newly introduced Merida bike is already available in a trail-ready version with 120 millimeters of suspension travel in other countries. One could say: the perfect specimen to highlight the conceptual differences both on the scales and on the trail.

To do this, the factory-installed 100 millimeter fork had to make room for a 120 millimeter version. The carbon seatpost was replaced with a Rock Shox Reverb AXS. It was crucial for us to maintain a comparable basis for this differentiation. Therefore, we swapped the Rock Shox SID SL Ultimate for a SID Ultimate. The fork, without the ‚SL‘ designation, offers 20 millimeters more travel but operates at the same level of quality.

The first astonishing fact: the fork with 120 millimeters of travel weighs only 158 grams more. Along with the additional 20 millimeters of travel, you also get beefier stanchions. The 100mm fork uses 32mm stanchions, whereas the 120mm version from Rock Shox boasts 35mm stanchions. This makes the 120mm option noticeably less prone to twisting, especially when braking hard or railing through bermed corners. The increased steering precision not only enhances performance but also benefits the overall function, as less twisting equals less friction during compression.

Swapping out the carbon seatpost for the Rock Shox Reverb AXS is a breeze thanks to its wireless operation. Dropper posts that use a mechanical cable require a frame that’s prepped for cable routing and a bit more mechanical expertise. The Reverb AXS, on the other hand, can be universally fitted to any bike without these prerequisites. The upgrade does come with a heftier impact on weight, adding about 500 grams more than swapping the fork.

An additional weight of 644 grams is manageable considering the modifications, but it still has an impact. Especially in the Cross Country or Marathon sector, every biker is vying for the coveted KOM titles on the climbs. Hence, we ran a realistic experiment through your power calculator. What are the theoretical consequences of hauling an extra 644 grams up the notorious Tremalzo Pass at Lake Garda? Starting from Riva del Garda, you face 39 kilometers and 1828 vertical meters before you can traverse the legendary tunnel at the mountain pass.

If you’re cranking out an average power of 200 watts on the pedals, with a body weight of 80 kilograms riding a 9.4-kilogram bike, it’ll take you 2:37:11 hours to reach the summit. Keep all other factors constant and only switch the bike’s weight to 10.1 kilograms in the calculation, the calculator churns out a ride time of 2:38:13. Our conclusion: To reach the tunnel in the same amount of time with both setups, you’d have to push an extra watt (that’s 0.5%) throughout the entire climb with the 120-millimeter bike.

The additional 0.5% power demand might seem manageable on the trail, but the logical counter-question arises: What’s the payoff? We put the Merdia Big.Nine through its paces both as a classic XC setup and in the 120-millimeter travel version on the same test loop. In back-to-back testing between the two setups, it becomes immediately apparent that not only the travel, but also the geometry is transformed.

After the rebuild, the riding position of the bike becomes significantly more upright. Notably, the reduced reach can be felt distinctly, whether you’re seated or standing on the bike, even with the 120mm fork. The bike retains its sporty vibe post-conversion, albeit in a less pronounced manner. This should actually appeal to riders who are into longer tours. Will the anticipated wow-factor in downhill performance be evident in a head-to-head comparison?

A particularly steep section right at the entrance of the first trail clearly sets the stage—the difference is stark. While having extra travel at the top of the steep section isn’t yet noticeable, the installed dropper post quickly becomes the star of the show. Where the rigid post previously forced you into a posture, that left your backside trailing behind the saddle and your torso nearly lying on it, now you are able to maintain a more centered position on the bike. From this neutral stance, you can execute maneuvers such as a bunny-hop or a quick change in direction despite the steep terrain. That is something which was unfeasible with the previous compulsory posture.

While the dropper post shines in every descent, allowing ultimate freedom of movement, the additional travel on the fork operates more subtly. It becomes noticeably beneficial when one encounters into extreme conditions. Upon compressions or when sticking landings after jumps, the 120mm fork has significantly more in reserve. Riding smoothly over mellow trails, the 100mm Rock Shox Sid SL performs with absolute sensitivity, leaving little room for criticism. However, on rougher terrain or during harder braking, it’s evident that the stouter 35mm stanchions twist far less than the slimmer 32mm stanchions of the 100mm fork.

We’ve even dared to conduct a head-to-head comparison between a 120mm hardtail with a dropper post and a race full-suspension bike to see which design promises more potential. Although you might assume that a full-suspension bike is more downhill-oriented, the reality on the trails tells a different story. The 100mm of travel in the rear of the Cervelo ZFS 5 do soak up bumps, providing steady traction and more comfort than the hardtail.

But when the going gets tough or the trail gets steep, you’re better off with a dropper post on a hardtail than a full-suspension setup in the rear. Sure, the full-suspension bike eases the strain on your entire upper body over long distances, but that high seat post won’t do you any favours when you need to bunny hop over a log. Just as fascinating, both the Merida Big.Nine and the Rose PDQ, outfitted with 120mm travel and a dropper post, tipped the scales at about the same weight as the classic 100mm-travel race full-suspension bike.