Trek Procaliber hardtail gets 200g lighter and longer, lower, slacker too

The Trek Procaliber uses a new IsoBow design for a bit of compliance and sheds Knock Block to save weight.
Provided photos.

The new Trek Procaliber XC-race hardtail sees major updates, with fresh geo, longer travel, a new IsoBow design, and a 200g lighter frame weight. And it’s the rare 2024 bike that’s 29er only with zero in-frame storage and zero flip chips. Trek positions the bike as a good choice for XC racers who prioritize a lighter weight over comfort, high school athletes looking for an edge, and even gravel bikers who want to tackle especially rough rides.


Trek Procaliber key updates

  • 120mm fork, up from 100mm
  • IsoBow instead of IsoSpeed
  • 1150g frame weight, down from 1350g
  • Slacker HTA, steeper STA, longer reach, lower BB
  • No Knock Block

Trek Procaliber geometry

This is the third generation Trek Procaliber, and no surprise, it’s longer, lower, and slacker than the bike it replaces. Up front, the head tube angle slackens to 67° and is designed around a 120mm fork. The seat tube angle gets a little steeper to 74.3° and the reach extends an extra 10mm to 460mm on size large frames. And yes, the bottom bracket is lower too.

IsoBow frame compliance

The new Trek Procaliber makes use of a design the brand is calling “IsoBow” to add a bit of compliance to the rear of the frame. The new design ditches the IsoSpeed hardware used previously and is said to deliver a similar ride feel via extended, flex-tuned carbon seat stays. The Procaliber uses a floating brake mount that’s designed to isolate braking forces from seat stay flex for more consistent braking.

Trek also increased rear tire clearance to fit tires up to 2.4″ wide. There’s no Knock Block this time around, and the frames still include two full-size water bottle mounts. Eliminating Knock Block and simplifying the seat stay design allowed Trek to shave a full 200g off the frame weight.

Only the Trek Procaliber 9.5 build will be available in North America, though higher-level 9.6 and 9.7 AXS builds will be available in other regions. Alloy Procaliber builds, released previously, are also available.

  • Price: $2,499 for the Trek Procaliber 9.5
  • Buy from Trek