Cervelo ZFS-5 Tech And Race Review
When a road-centric brand like Cervelo finally steps into the full-suspension MTB world, it tends to get our attention. The Cervelo ZFS-5 has been in the works over the last year or two, and if you're anything like me (an extreme XC nerd), you’ve been seeing spy shots of it for a little bit as well. Unfinished frames, custom links, watching it being raced at XCO’s, the whole idea of a road bike company making a full suspension mountain bike started as a marketing ploy in an attempt to get more brand recognition, rather than to just make a mountain bike to make a mountain bike. Team Jumbo-Visma! You love them, or you hate them, but you've definitely heard of them. One of the biggest and most well funded road racing teams in the world. Jonas Vinnagard took the 2022 and 2023 Tour De France with them, they had rider Primoz Roglic win the Giro D’ Italia this summer of 23’, and Wout Van Aert is a fan favorite power house, dominating cyclocross as well as winning TDF stages, and having legendary bike handling skills. Jumbo-Visma is one of the most well known teams out there, and includes American rider Sepp Kuss, a fan favorite Colorado native and Tour of Utah winner.
Jumbo-Visma wanted to get more recognition, and was tasked with having two riders start competing on the XCO UCI world cup MTB circuit. The idea here was to have some more observance in the off-road world from a company that had previously only really raced drop bar bikes. Most people assumed that they would ride the Santa Cruz Blur, the full suspension XC bike from Cervelo’s sister company, Santa Cruz Bicycles. But the issue here was that Jumbo-Visma didn't want to just ride their sister company's bike, rather they wanted something new. So, to help fuel this off-road focused marketing scheme, Cervelo started the design of a new XC MTB for the first time. When the bike was first released, a lot of people disregarded it saying things like “Oh it's just a repainted Blur” or my favorite “Oh look a curvy Blur!”. To be fair, you can see where they are coming from. With similar specs, geometry, and the frame itself looking so similar to the Blur, it's hard not to think Cervelo asked Santa Cruz to copy their homework, and Santa Cruz said yes, just change it a little so the teacher doesn't notice. The real story is more like Cervelo just asked to see Santa Cruz’s notes to kickstart the design process. With a jump start from Santa Cruz, Cervelo set out to make a full suspension race bike worthy of the fastest road team in the current age. Besides the Cervelo's more smoothed out and curvy frame characteristics, it also has different geometry and a different carbon lay up than the Blur. So yes, not just a Blur.
After riding a Santa Cruz Blur TR for most of the current season (the better part of multiple months) then hopping on the Cervelo, I was surprised at how different it actually felt. I was expecting it to be different, but not by as much as it was. It’s a totally different bike, more than I thought for sure, and you’ll see how so in a moment. Beyond that though, comparing the Cervelo ZFS 120 to the Blur TR, in a size large the Cervelo has a 457mm reach, 610mm stack height, 66.6° head angle, and 75.0° seat tube angle. The LG Blur TR has a 457.5mm reach, 606.5 stack, 67.1° head angle, and 74.9 seat tube angle. I ordered this bike as a frame only and built it up with the intent of something that could be raced and raced hard when wanted, but also spend a lot of time as a more comfortable “down country” bike, with the only change being a shorter stem. Expecting to race the Park City Point 2 Point on it, the fact I was going to race 78 miles and 10,000 feet of vertical on singletrack and rough terrain was in the back of my mind. The ending build would need to be lightweight but also comfortable to reduce fatigue, which led me to spec it with a 150mm dropper, a more capable race tire, and a 120mm fork. I also decided for the first time on my bikes in over two years, I wanted mechanical shifting. I love AXS, don’t get me wrong, but seeing as AXS will probably take over all drivetrains within the next year, I wanted one final mechanical “hoo-rah!” bike before it does. Here's how the full build breaks down:
|Frame||Cervelo ZFS-5 120 Khaki/Moss LG|
|Fork||Fox 34 SC Factory 120mm|
|Stem/bar||Cervelo 80mm/-8° w Salsa SaltFlat carbon 720mm|
|Grips||Wolftooth Echo Lockon, Espresso|
|Seatpost||30.9 Fox Transfer Factory 150mm w/ Wolftooth ReMote Espresso|
|Saddle||WTB Silverado Carbon rail/shell|
|Cassette||Sram X01 10-52|
|Cranks||Sram X01 170mm Lunar|
|Chain||Sram XX1 black|
|Chainring||Wolftooth DropStop 36T on Power2Max Ngeo power meter|
|Shifter/derailleur||Sram X01 mechanical, Lunar gray|
|Brakes||Sram G2 Ultimate 4 piston|
|Rotors||Sram HS2 180mm f/r|
|Wheels||Syncros Silverton 1.0, 30mm internal|
|Tires||Maxxis Ardent Race 29 x 2.35, MaxxSpeed EXO|
|Pedals||Shimano XTR, -3 spindle|
|Extras||Wolftooth centerlock rings, seatpost clamp, chainring bolts, bottle cage bolts, and top cap in the Espresso colorway|
When you hop on the Cervelo and start pedaling up the hill on one of your favorite loops, something immediately feels different. The rear end of the bike feels (and yes this is the best way I can describe it) “springy”. It feels like it's easy to pop over rocks while climbing, and whatever power you put into the bike, the bike gives you something back, climbing as fast as you could want it too. It climbs extremely well, taking tight turns with ease, but keeps traction and stays comfortable. It's not as flat out efficient as lets say, the Orbea Oiz, but it pedals extremely well. Getting onto the flats, the bike blew me away with how fast it covered ground, or at least how fast it felt. Time and Strava will tell for sure… This could be attributed to the shock tune, as Cervelo and Santa Cruz both claim the same leverage curve between the Blur and ZFS, so the only difference is that I rode the Blur on a SID Luxe rear shock, vs a Fox Float on the Cervelo.
When I first bought this bike frame, the Cervelo Representative informed me that the carbon layup was completely redesigned from the Blur, but they wouldn't tell me how. So it was my job to figure out what that difference is, hopefully reducing the placebo effect by not knowing what was supposed to be different. So far, I definitely noticed the springiness in the rear while climbing, but what about how the bike descends?
Right away, that springiness comes into play on the descents. Quick line changes, goofing off, popping tables or short manuals through rollers (as in two rollers is only how long I can hold a manual anyways) and general descending, this bike was extremely playful and poppy, more so than most 120mm XC bikes I’ve ridden. This caught my attention, especially considering that this bike has the longest wheelbase and slackest head angle of any 120mm XC bike we carry. Having that longer, more stable wheelbase and head angle to smash rock gardens with reduced fatigue but not losing a whole ton in maneuverability was awesome.
Speaking of smashing rock gardens, holy cow. That rear end does not move through the chunk, it’s so planted. You can drive hard through chunk, or push through a berm as hard as possible, and compared to a Blur or other similar bikes, that rear end is way stiffer. Even on flow dedicated trails with lots of opportunity for lots of speed and big berms, you can drive the bike into berms HARD with very little flex or movement from the rear triangle. After riding the bike for two weeks, I followed up with our Cervelo representative, and my conclusion was confirmed. The bike was designed to be very vertically compliant for comfort and responsiveness, leading to that feeling of springiness I was mentioning. With this, the carbon was laid up for extreme lateral stiffness, hence the “planted” feeling from the rear as well. Lateral stiffness, and vertical compliance. Sounds like the best of both worlds huh? I mean nothing is truly the best of both worlds or without its pros and cons, but boy does this bike feel simply, just, good.
Another note on this bike that I haven't seen from other reviews, or heard at all from Cervelo, was the noise. Or lack thereof. Cross Country bikes are not normally quiet machines. With lots of extra cables, minimal chain slap protection, short chain stays, no weight-saving tube in tube routing, short travel forks, and thin casing tires, they tend to make a lot of noise. If you ride a trail bike for a while then hop on a race-oriented XC bike, you will for sure notice how much racket they make. This simply was not the case with the ZFS. In the first descent I did on it, all I could hear was my tires on the dirt, nothing else. This threw me off guard, after getting used to the cable slap noise of the Blur for the last 5 months. This is probably one of the things I love the most about this bike; if there's one thing that makes a long race like Point 2 Point endurable, it's a quiet ride.
The Park City Point 2Point race itself, is a brutal course covering 78 miles of single track in Park City, Utah taking you up and down 10,000 feet of vertical across the surrounding valley. The course starts by rounding Round Valley (haha ;) ) in a loop, climbing Deer Crest towards Deer Valley, doing the Team Big Bear Climb, Mid-Mountain to Johns 99, then to the PCMR trail system, Johns Trail to Jenny’s, to Keystone, descending down from that and 9k to the base of the mountain via CMG, then climbs all the way to the top again! From there, you take Armstrong up, back on Mid Mountain, to the UOP trail and back down, finishing at the Olympic Park trail system. Not for the faint of heart, the average finish times are around 9 hours, with the fastest rider finishing in 6:10, the back end of the race at over 13 hours. This year saw a fantastically beautiful day, cloudy and averaging 60 degrees. You could not ask for better racing weather. I am so glad I tried this race, exploring so many of Park City’s trails in a sustained effort, with a fantastic community and lots of racers out on course. If you are ever up for a challenge like none other, definitely try this one out! With some decently rough single track, but long hours in the saddle, the Cervelo ZFS-5 was the perfect tool for the job. If you’re an XC racer looking for something a little bit more relaxed, or on the flip side if you’re a trail rider looking for something just a little more XC-oriented, the ZFS-5 120 is the right tool for the job. If you want something that's more of an all out race bike, consider the ZFS-5 100. With a lower front end, longer reach, and steeper head tube angle, the ZFS-5 100 is more for the out and out racer. With a range of builds for everyone, this is definitely a bike to add to the list when shopping around. Very well suited to multiple things compared to the XC bikes I’ve ridden before, and being able to go from 100-120mm of travel with nothing but a stroke change, this is one of the most versatile XC bikes we carry. Not necessarily the best in any area, but super versatile.
*Disclaimer: Please don't drill your steer tube for brake hose routing like this bike, it will void your frame, fork, and brake warranty and can be considered unsafe*