YT has unveiled the fourth generation of its Tues downhill bike at Fort William ahead of the 2024 UCI Downhill World Cup.Like its predecessor, the new Tues uses YTs Virtual 4 Link (V4L) suspension system, providing 200mm of rear travel. But the linkage now features a Flip Link flip chip, enabling you to run the bike with a mullet wheel size for the first time.The Tues is only available in two spec levels built around a carbon fibre frameset. Prices start at 3,999 / $3,990 / 3,999 for the Core 2, while the top-of-the-range Core 4 is priced at 5,999 / $5,990 / 5,999.Weve taken a close look at YT MOB rider Oisin OCallaghans new YT Tues at Fort William.Carbon-only constructionThe new YT Tues is only available with a carbon frame. - Max Wilman / Our MediaThe first thing that stands out from the previous Tues is the new integrated fork bump-stops at the top of the down tube.Weve seen many manufacturers include this feature on their latest downhill bikes, including but not limited to the latest Saracen Myst.The design protects your frame and stanchions when over-rotating the handlebar.There are now integrated fork bump-stops. - Max Wilman / Our MediaThe bikes frame is made from YTs Ultra Modulus Carbon Fibre.Unlike the previous generation of the Tues, there is no aluminium option. We asked YT if there was one in the pipeline, but weve yet to hear back.Flip Link linkage for mullet compatibilityThe bike has gained a flip chip so you can run a mullet-wheel setup. - Max Wilman / Our MediaThe bike uses the V4L suspension system, which YT says provides sensitivity off the top, with good mid-stroke support and plenty of end-stroke progressivity.Built into the linkage is YT's new party piece, the Flip Link flip chip, which enables riders to swap between a full 29in wheel or 29in front and 27.5in rear mullet-wheel setup.Previously, you had to swap out parts of the linkage to adjust the bikes geometry for a mixed setup, but now the Flip Link enables you to switch between 29in and 27.5in wheels.While this is not new tech, it will be a welcome feature for those looking for a mullet downhill bike and wanting to capitalise on YTs reputation for offering value for money.SRAM UDH and more practical tweaksThe fourth-generation bike has also adopted SRAM's UDH. - Max Wilman / Our MediaYT has also updated the rear dropout to use SRAMs Universal Derailleur Hanger (UDH). This should make finding spares at the park or track a lot easier.Replaceable shock hardware inserts are now used too, which YT says will prevent you having to sacrifice the frame if you strip the bolt threads.In another win for home mechanics, YT has replaced the press-fit bottom bracket with a threaded bottom bracket hopefully making for less creaky cranking and easier servicing.A large frame protector on the underside of the down tube provides cover from rock strikes.The driveside chainstay and seatstay feature wrap-around protectors to minimise chain-slapping noise.YT Tues geometryThe Flip Link means you can adjust the head angle. - Max Wilman / Our MediaThe new YT Tues will be available in five sizes, ranging from S to XXL, with all bikes being mullet-compatible.Reach measurements increase in 20mm increments, with the size S measuring 430mm and the XXL topping out at 510mm 15mm longer than the previous model.The Flip Link flip chip adds head-angle adjustability, giving you the choice of 63.2 degrees or 63.5 degrees.This also gives 5mm of BB height adjustment, though these cant be tuned independently.YT has given the bike size-specific chainstay lengths as well as a separate adjustable long/short flip chip that brings 5mm of adjustment to the rear end.S to L frames feature 438mm or 443mm chainstays in the MX position and 440mm or 445mm in the 29in position.The XL to XXL models are 10mm longer at 448mm or 453mm, and 450mm or 455mm.Oisin OCallaghan's custom YT Tues Core 4O'Callaghan's drivetrain uses a rear derailleur and cranks from TRP. - Max Wilman / Our MediaYT-sponsored riders have the option of custom spec on their downhill bikes.OCallaghan has decided to spec Foxs gold 50th-anniversary Float 40 Factory suspension fork on his YT Tues Core 4 instead of the standard orange fork.The Irish rider runs his fork with 94psi and the DHX2 Factory rear shock with a 475lb coil.O'Callaghan is running TRP brakes. - Max Wilman / Our MediaHe also rides with TRPs DH-R EVO brakes matched to 223mm rotors.His rear derailleur of choice is TRPs EVO 7, which is paired with Ochains latest unadjustable anti-pedal-kickback chainring. The chainring is claimed to improve suspension performance by reducing the chain's effect on the system.The 20-year-old uses Continentals Kryptol tyres rather than the Maxxis Assegai mountain bike tyres found on the stock Tues Core 4 bike.Oisin O'Callaghan has made a few custom tweaks to his Tues Core 4. - Max Wilman / Our MediaO'Callaghan also appears to have a different Renthal handlebar and mountain bike grips from the off-the-shelf bike.Despite the option to run the new Tues with a mullet setup, OCallaghan uses 29in wheels front and rear.2024 YT Tues specs and pricesYT Tues Core 2Fork: RockShox Boxxer Base, 200mmShock: RockShox Super Deluxe Coil SelectDrivetrain: SRAM GX DH 7-speedBrakes: SRAM DB8Wheels: SunRingle Duroc SD 37 CompTyres: Maxxis Assegai DH 2.5 3C MaxxGrip DH TRPrice: 3,999 / $3,999 / 3,999YT Tues Core 4Fork: Fox Float 40 Factory, 200mmShock: Fox DHX2 FactoryDrivetrain: SRAM XO1 DH 7-speedBrakes: TRP DH-R EVOWheels: Crankbrothers Synthesis DH Alloy I9Tyres: Maxxis Assegai DH 2.5 3C MaxxGrip DH TRPrice: 5,999 / $5,999 / 5,999