It's been a hot minute since we saw the last update of Trek's Slash and, today, the Wisconsin-based brand has completely overhauled its enduro ripper. Not only does it get longer dropper insertion, a revised geometry and a load of frame protection but it's also equipped with a high pivot suspension layout, as well as a bunch of idler pulleys.

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The Slash is Trek's big travelled bike that's designed for use between the tape but also to take riders over the gnarliest of trails and is capable of getting them back up to the top. Trek calls its latest iteration, 'the backcountry battle axe'.

For 2023, the Slash gets a host of geometry updates, including a slacker head tube angle at 63.5-degrees which is adjustable by plus or minus a full degree thanks to adjustable headset cups that are available aftermarket. The effective seat tube angle sits at 77-degrees and there's a 488mm reach on a large frame. Other tweaks include size-specific chainstay lengths and seatpost insertion has increased by around 80mm, depending on the size frame you pick.

Slash - R-Dog and Casey - S Needham.jpg, by Liam Mercer

This year's Slash takes a departure from a full 29-inch wheel setup and, instead, goes for a mixed wheel size with a 29-inch front wheel and a 27.5-inch (650b) wheel at the rear. Trek has chosen this route as it believes that the big front will help roll over obstacles better while the little rear wheel increases clearance over the back of the bike and retains agility.

However, riders can run full 29-inch setups thanks to an interchangeable bolt-on lower shock bracket. The small frame size is 27.5-inch at both ends for easier handling for smaller riders.

However, unlike bikes from other brands, the small frame comes with few compromises as Trek states that it'll fit up to a 170mm dropper post with 290mm insertion, 85mm than before. This size also gets downtube storage and space for a water bottle in the front triangle.

2023 trek slash pivot.jpg, by Liam Mercer

The elephant in the room is that the Slash has gone with a high-pivot suspension layout on this bike, which allows the rear axle to move rearwards with the force of bumps. This means that the rear wheel shouldn't hang up on square hits, resulting in better retention of momentum. 

As a result, the Slash gets not one but two idler pulleys with the upper being oversized and featuring 19 teeth. Trek reckons that this size is more efficient and its placement reduces pedal kickback that's caused by chain growth – a defining factor of Aaron Gwin's famous chainless win.

2023 trek slash upper idler.jpg, by Liam Mercer

The lower idler then helps mitigate chain growth from under the chainstay, while keeping the chain from tugging on the derailleur cage.

As expected from a Trek bike, this one gets the brand's Active Braking Pivot tech which has been added to keep the Slash's suspension active when under braking. It's also said that this system has allowed the bike's designers to tune anti-squat and anti-rise independently. And speaking of anti-squat, Trek claims that it sits just above 100% throughout the travel range, which should lead to some mighty efficient pedalling.

2023 trek slash lower idler.jpg, by Liam Mercer

Elsewhere on the bike is a host of cool features, including a rear fender that's been designed specifically for this bike but it has to be removed if running a 29-inch rear wheel as there's not enough space. The Slash benefits from dual-density downtube guards that can be replaced if badly damaged.

On top of those guards, there is an impact-resistant film underneath the paint for even more protection.

At the rear, there's a chainstay guard that's been designed to reduce noise and, at the downtube, there's storage as expected of the Slash. However, this time, it's cut with a larger opening and its latch is easier to reach, says the brand. All of the plastic gubbins are made from recycled plastic, too.

2023 trek slash storage.jpg, by Liam Mercer

The 2023 Trek Slash lineup consists of nine builds with one alloy frame only –the balance is all carbon fibre. Throughout these builds, customers can expect Shimano XT to XTR cable actuated shifting, SRAM GX AXS through to XX AXS T-Type drivetrains. There's also a choice of Fox and RockShox suspension.

There are five sizes available from S up to XL and prices start at £4,250 for the Slash 8 and go up to £11,750 for the range-topping 9.9 XX AXS T-Type.

• www.trekbikes.com

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