FIRST RIDE - YT's New TUES MK4 DH Bike - Mountain Bike Feature

Earlier this week, we joined YT to check out the latest iteration of their TUES downhill bike. A staple in YT's product line for over a decade and a bike that's seen plenty of success throughout the years, it was overdue for a facelift. Shoot, the last update came back in 2019. After seeing Vali Höll and Jack Moir ripping this off-season on a diaper-wrapped DH bike, we knew it was only a matter of time before the cover came off and we found out what the new TUES was all about.

TUES MK4 Highlights

Ultra Modules carbon frame
200mm of travel front and rear
Dual 29-inch or MX wheel setup via FLIP LINK adjustment
V4L suspension design
63.2 or 63.5-degree head tube angle
+/-5mm bottom bracket height adjustment
5mm chainstay length adjustment at rear axle
Threaded bottom bracket (previous TUES used a press fit BB)
Replaceable fork bumpers and frame protection
Double-sealed pivot bearings
UDH equipped
5 sizes: S-XXL
Weight (size large, Core 4 Build): 36.7 lb (16.6 kg)
MSRP: Core 2 - $3,999 USD // Core 4 - $5,999 USD

Q & A with YT Sr. Manager of Product Development, Frank Dorr

It's been quite a few years since we've seen any changes hit the TUES model—the last real update came in 2019 with the introduction of the 29-inch Tues. What were the main goals when YT set out to develop a new version of the TUES?

With the MK4, we are aiming for the top spot in the world of high-performance DH bikes, no doubt. We are always in pursuit of creating the fastest bike while ensuring it is user-friendly and fun to ride. This is a challenging but exciting goal. By offering 5 dedicated frame sizes and integrating a variety of fine-tuning options on the frame itself, the TUES MK4 is the most customizable bike we have created thus far. Wheel size, bottom bracket height, chain stay length – build it like you want it. Each feature is engineered and designed as a straightforward and simple process so that everyone can do it.

The bike continues to use your Virtual 4 Link suspension design. What type of performance or characteristics were you seeking with the latest kinematic package? Why did you decide to stick with the same suspension layout instead of going with a different one?

By actively involving our R&D test riders and our sponsored riders for feedback, we made the decision to fine-tune our V4L linkage design and not throw it overboard. It has proven its capabilities over the years.

I saw a photo floating around of an idler pulley equipped TUES this off-season. What was that all about?! Why don't we see it on the production version?

Indeed, our team is testing different stuff – learning never stops, right? Keep your eyes peeled...

Let's talk geometry: the previous TUES had a fairly typical geometry package for a downhill bike, but it was also a little outdated in some areas. Has the geometry changed very much, and if so, what were you seeking to achieve?

The geometry, in general, got a basic update. We have expanded our range to include 5 distinct frame sizes, providing a broader selection to ensure an optimal fit for your body height, intended use, and riding style. By incorporating 2 additional sizes with reduced reach, as well as revamping the L, XL, and XXL sizes, we have further refined the bike's customization options.

More reach, more stack, longer chain stays, and lower BB cater to the requirements of high-speed and challenging downhill trails, delivering an increased level of stability and balanced ride feel. It is crucial for this category of bike to hop on and feel confident. Otherwise, you won't have much fun—not in the bike park or on a racetrack. By crunching all the numbers, we still kept the playfulness.

Does the bike use size-specific chain stays?

We do have basically two different chain stays. With the rear axle length adjustment and the FLIP LINK, we end up with 4 different chain stay length settings (horizontal measurement). The S, M, and L frame sizes feature seat stays measuring 438/443 mm MX (440/445 mm 29), while the XL and XXL sizes boast 450/455 mm 29 (448/453 mm MX) chain stays.

The previous TUES had no adjustability built into the frame, but now riders have a few options to fine-tune their setup. Run us through what those adjustments are.

If you prefer to change the wheel size, the FLIP LINK offers a convenient solution without any major complications. By easily disassembling the link, flip it to the "other" side, and reassemble the system. The hardware is laser-marked to ensure you set it up as you want. This straightforward process allows you to seamlessly switch to the preferred wheel size.

The bike will be available as a MX version (27.5 rear wheel) in size S and M, while the remaining sizes L, XL, and XXL will come equipped with a full 29er wheel setup for both the front and rear.

Offering the bike in sizes Small and Medium with the smaller rear wheel not only creates more "bum" clearance to avoid any skid marks on the pants, but it also requires less bodywork to move the bike from one side to another, e.g., for cornering, due to the reduced distance from the rear wheel axle to the ground. For L, XL, and XXL, the 29" rear wheel works great because inseam lengths and body levers are bigger. There shouldn't be a struggle with the rear wheel touching the bum, and no hard work is required to shift the bike from one side to the other. Here, the larger rear wheel offers a smoother ride due to its ability to roll over obstacles easier, better traction, a stable ride feel, and carries momentum well.

There is also a flip-chip integrated into the lower shock mount, allowing riders to switch between "REGULAR" and "LOW" positions. The "regular" position is set up as the default but switching to "low" will lower the BB height by 5mm and slacken the ST/HT angle by 0.3 degrees.

REGULAR = (On TUES MK3 this was the "low" position) It creates slightly more pedal clearance, set up for slower, tighter, more technical terrain

LOW = improved descending capability, lower center of gravity, faster more open terrain - super greedy riding. We recommend riding the TUES MK4 with the chain stay length in "long" position when the flip-chip is in LOW.

To ensure optimal weight distribution, we adjusted the chain stay length of the TUES MK4, taking into account the bike's increased front-center resulting from its modernized geometry. An innovative feature called the integrated chain stay length adjustment (ILA) allows riders to fine-tune their bike's characteristics. By opting for either a longer or shorter chain stay setup, riders can achieve a well-balanced weight distribution or a more playful rear end, catering to their individual preferences. Once the flip chip position is set up to the preferred position and the brake mount adapter is switched accordingly, the bike is ready to go.

The selected headtube dimension (top inner diameter = ZS49mm/bottom i.d. = ZS56mm) optimally balances the requirements for accommodating a double-crown fork with ample clearance, ensuring stiffness for precise steering, and seamlessly integrating reach adjustment headsets. Having this standard in place the "Reach Adjuster" from "Workscomponents" can be installed without any hustle. With that headset the reach can be adjusted by +/- 6mm.

Getting into the nitty-gritty of the frame, what are some details that stand out?

We follow our own protocol to have dead silent bikes (unofficially called the noise-canceling program). The frame protection got updated (Downtube, chain stay, seat stay). Part of the program is also the integrated fork bumpers, which not only protect the frame from fork impacts but also offer ample clearance for most available dual crown forks.

All hardware is very easy to work on; only a handful of mostly common Allen keys are needed. Leveraging our DH World Cup experience, we developed replaceable shock mount hardware. So once the threads are messed up, that doesn't mean the end of your front triangle anymore. It's super easy to replace.

Pivot point bearings are double-sealed to guarantee a long life and less struggle for riders. Cable routing is fully integrated and trouble free. We firmly believe that the amalgamation of these seemingly minor details is what distinguishes a great product from merely a good one.

The TUES MK4 also uses a UDH—a forward-thinking feature provides reassurance to riders, as it offers easy resolution in the case of any rear derailleur-related issues. Thanks to its widespread availability at numerous bike shops worldwide, buying a replacement or addressing any concerns becomes a hassle-free process.

YT has a huge presence in the freeride scene. Is this new bike strictly racer-focused? Will the TUES 27.5 continue to serve riders looking to hit jumps and slap corners? Or is this new version targeting those riders as well?

The new TUES is specifically designed to excel on the world's most challenging racetracks, making it the ideal choice for competitive racing. Its exceptional capabilities and features allow riders to conquer even the toughest terrain with confidence and precision. However, the TUES doesn't limit itself to the race scene alone. It effortlessly adapts to various riding environments, including fun days at bike parks and local tracks, regardless of the features they offer.

Whether it's tackling jumps, berms, or any other obstacles, the TUES ensures a remarkable handling experience, making it suitable for both high-performance racing and enjoyable recreational rides. So, no matter if you tuck down to save time or foot out - flat out - TUES MK4 can handle both.

What frame material is the bike offered in?

We offer the bike in Ultra Modules CF, our highest class of carbon fibers.

When will the bike be available, and how many builds will there be to pick from?

The TUES MK4 will be available from May 2nd in Core 4 and Core 2 build specs.