The Vitus Sommet 297 AMP is a fairly lightweight, 170mm-travel burley mullet-wheeled enduro mountain bike. Although the Sommet has enduro riding firmly in its sights, its modern geometry mixed with its lightweight feel, mullet-wheel design and high-spec components should make it an incredibly reactive and agile ride with a light-footed feel. The mixed wheel size is well known within the mountain bike scene to provide the best of both worlds when it comes to handling. Thanks to the 27.5in rear wheel, mullet bikes have snappy handling, yet retain their bump-munching, grounded feel over rougher tracks thanks to the 29er front wheel.
There’s a 27.5in Nukeproof Horizon V2 wheel at the rear. Vitus has called this bike a “manual-loving mullet bike”. Compared to previous ‘non-mullet’ bikes I have ridden, it should be much easier to pop the front wheel up when needed… or wanted. Its front triangle is made from carbon fibre, while the rear is alloy. The frame is fitted with some of the highest-spec parts on the market, which helps keep overall weight for my size medium down to 15.1kg. That weight figure should cement the Sommet’s agility and light ride feel.
Vitus Sommet 297 AMP specification and details
Up front is a 29in wheel and RockShox Zeb Ultimate fork with 170mm of travel. The bike’s frame details include built-in soft rubber chain-slap protection on the seatstay and chainstay. It has down tube protection to limit any potential damage from rock strikes. The cables are routed internally through the frame and it has a BSA threaded bottom bracket. There’s one set of mounts for a bottle cage that can fit up to a 750ml bottle.
RockShox supplies a Super Deluxe Ultimate RCT shock. The bike has a Horst-link suspension design with 170mm of travel, paired with a RockShox Super Deluxe Ultimate RCT shock. Up front is a 170mm RockShox Zeb Ultimate fork built for 29in wheels. It’s fitted with a pair of Nukeproof Horizon V2 wheels, matched with a Maxxis Assegai up front and a Maxxis Minion DHR II out the back. The groupset consists of SRAM Code RSC brakes with 200mm rotors and a SRAM X01 Eagle 12-speed drivetrain, with a 10 to 52-tooth cassette and a 30-tooth narrow/wide chainring.
The 12-speed gearing comes courtesy of SRAM X01 Eagle. The RockShox Reverb Stealth dropper has 150mm of drop and a Nukeproof Horizon Enduro saddle mounted to it. Finishing off the contact points is a pair of lightweight Nukeproof Horizon V2 Carbon Riser bars at 760mm wide. These come with Nukeproof Sam Hill super-soft grips.
Vitus Sommet 297 AMP full specification
- Size: M
- Weight: 15.1kg (33.28lb), size M without pedals
- Frame: T700 carbon fibre front triangle, 6061-T6 aluminium rear
- Shock: RockShox Super Deluxe Ultimate RCT
- Fork: RockShox Zeb Ultimate 29in, 170mm travel
- Shifters: SRAM X01 Eagle
- Derailleurs: SRAM X01 Eagle
- Cranks: SRAM Descendant carbon crankset (1×12)
- Wheelset: Nukeproof Horizon V2
- Tyres: Maxxis Assegai (f), Maxxis Minion DHR II (r)
- Brakes: SRAM Code RSC with SRAM Centerline 200mm rotors
- Bar: Nukeproof Horizon V2 Carbon Riser, 760mm
- Stem: Nukeproof Horizon, 50mm
- Seatpost: RockShox Reverb Stealth Dropper, 150mm drop
- Saddle: Nukeproof Horizon Enduro
Vitus Sommet 297 AMP geometry
|Rec rider height (cm)||160-170||170-178||178-190||190-201|
|Seat tube length (mm)||380||410||440||470|
|Effective top tube length (mm)||568||597||621||645|
|Chainstay length (mm)||435||435||435||435|
|Head tube length (mm)||100||110||120||130|
|Head tube angle (low setting, degrees)||64||64||64||64|
|Effective seat tube angle (degrees)||76.5||76.5||77||77.5|
|Actual seat tube angle (degrees)||70.5||70.5||71||71.5|
|Bottom bracket drop (mm)||25 (f), 12 (r)||25 (f), 12 (r)||25 (f), 12 (r)||25 (f), 12 (r)|
|Bar width/rise (mm)||780/25||780/25||800/25||800/25|
|Seatpost insert depth (mm)||177||215||242||270|
The medium frame’s reach is 443mm. While this is shorter than I’ve been used to riding, it should make the bike a little easier to navigate on tight switchbacks and to pop the front wheel up over obstacles on the trail. Its 64-degree head angle is slack, which should make it easy to plough down my local steeps. It has a flip chip located below the rear shock, which steepens or slackens the bike’s head angle by 0.5 degrees and changes the bottom bracket height by 6mm.
The effective seat angle is fairly steep at 76.5 degrees, so nothing groundbreaking compared to my previous Saracen Zenith Elite LSL long-term bike at 75 degrees. This, paired with its efficient gearing setup, should make it a champion climber. That seat tube is also pretty short at 410mm. However, with the 150mm dropper, I can’t slam the post all the way down inside the frame.
This is something I’d like to experiment with, perhaps using a decent dropper such as OneUp’s 170mm Dropper Post. Making this change would enable me to get the saddle even lower between the knees for descending. The Sommet has a wheelbase of 1,225mm. With its mullet setup, it will hopefully provide a light, fun, manual-loving experience. And I do enjoy a good manual…
Why did I choose this bike?
Norco’s Shore is a 180mm-travel ‘freeride and park’ bike. Ultimately, I want to step up my riding and progress on to riding harder lines and push my abilities. I also need a regular workhorse that I can ride down my local trails and bike parks. The last ‘big rig’ bike I rode was the 180mm-travel Norco Shore, which is marketed as Norco’s freeride and park bike. That bike was a size large, and while I originally thought it would be far too big for me at 5ft 8in tall, I found the sizing spot-on. It made me feel very secure when hauling downhill. However, I chose the Sommet in a size-medium frame because this is generally the size I’m used to. I’m hoping this should allow me to manoeuvre it with greater ease between tight corners and rough blown-out sections, and pull those wannabe steezy shapes when airborne.
It was also hard to turn down the Sommet’s massive 170mm of travel front and rear, all damped by RockShox’s range-topping ZEB and Super Deluxe. My last long-term test bike was a hardtail. While I believe they make you a better rider, I wanted to take what I learned from riding that bike and push the limits of what this new bike is capable of, utilising the full amount of travel by hunting out large secret gaps and steep or heavy drops.
Vitus Sommet 297 AMP initial setup
Setup was pain-free. Initial setup was easy, and I found the seated position comfortable. Bar sweep was similar to what I’m accustomed to and the suspension only needed a short tune up to fit my needs. Having grown up riding more jumpy flow trails, I like to have my suspension set up a little firmer and with slightly faster rebound than others.
The same goes for the setup of the Sommet. I’d rather it had a little more spring in its step, enabling me to pick smoother lines between the rough stuff, hopping and popping between it all, if possible. I set the sag both front and rear to 20 per cent and dialled in a few extra clicks of rebound for a more poppy and reactive ride. This suits me better for my style of riding and hitting jumps.
Tyre pressures were set at 26psi after some initial experimentation. After playing with tyre pressures, where I’ve tried 22psi front and 24psi rear to improve grip, or 27/28psi for higher rolling speeds, I eventually settled on 26psi. This was enough air to stop the tyres from burping and losing pressure, but also offered the sort of grip and comfort usually associated with lower pressures.
Vitus Sommet 297 AMP ride impressions
There’s ample grip from the Maxxis Assegai up front. Initial impressions of the Sommet revealed a fun and playful ride, thanks to its weight and geometry figures. Its playful ride characteristics were cemented on my first ride, before I’d bedded the brakes in. I popped a manual and nearly flipped over the back, thanks to how easy it was to lift the front wheel. Fortunately, I was saved from crashing, and after some sketchy first runs on my local steep trails in southern England, I was able to bed the Code RSC brakes in fully. It gave me my first image of how this bike performs under pressure.
The first thing I noticed was how accurate the steering is. The grip from the Maxxis Asseagai up front made pinning down a high line over off-camber sections of trail easy. Blown-out corners with hardly any support were full of grip. The Sommet is the first mullet bike I’ve ridden. I found before too long that if you hit a well-supported berm with enough gusto the front wheel tends to lift on the exit and accelerates you down the trail. This caught me by surprise a few times and I’ve since adapted my riding style to fit this quirk. In most instances, I’d say it’s a bonus – as long as you’ve already spotted your exit.
The SRAM Code RSC brakes deliver plenty of bite. I’m not used to the power four-piston brakes offer, especially the Codes fitted to the Sommet, once they were bedded in. It took some time to get used to the power on tap, and to learn how to modulate that power. On the first few rides, I found myself skidding a little too often on fast, flat-out sections of trail. Ultimately, it meant I was entering corners too quickly because I was unable to maintain enough traction to slow me down efficiently.
I also found the Codes’ bite was so sharp that holding a manual up was trickier than with less powerful brakes. However, this is a nice problem to have. I’m hoping once my brain and body learn to work better with these powerful brakes, I’ll be able to increase my top speed and boost confidence. I’m hopeful they’ll offer a sense of safety and confidence when pushing the boundaries into those teeth-gritting speeds I’m not used to.
Vitus Sommet 297 AMP upgrades
A new dropper post is top of Max’s list of potential upgrades. I’m currently happy with the bike’s spec and setup, so finding upgrades might be tricky. I would like to change the dropper post for a version with 170mm of travel or more. I want to take advantage of the Sommet’s short 410mm seat tube and slam the post as far into the frame as possible, while it’s still lifting to my preferred pedalling height. Although the 150mm Reverb is a superb dropper, a post with more drop would suit me better.
I would also be interested to test a pair of alloy bars and high-end carbon bars, to feel the difference from the Horizon V2s. The stock bars feel a little too stiff under hand, so a day or two spent swapping bars trail-side would be an interesting way to tell the difference. Other than that, I’m going to make some subtle changes to the contact points around the bike, such as a comfier saddle, some suitable flat pedals and perhaps some yellow grips to match the detailing of the frame.