Trek’s IsoSpeed decoupler has been making the rounds on the brand's range of rigid trail and road frames, and now the American outfit has quietly added the mechanical pivot to is alloy Procaliber XC frames.
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The higher end 9-series carbon frames received the IsoSpeed treatment a few years back, but the lower end Procalibers were left out to dry. But, now Trek has trickled the technology down into some of its more affordable models.
For those who have been living under a rock for the past couple of years, the IsoSpeed decoupler is a mechanical pivot that allows the entire seat tube to flex independent of the top tube, to take the square edge off of big and small hits, and all without sacrificing any rigidity or efficiency.
The new frame also sees Boost hub spacing, a PF92 BB, 100mm of travel (except for the 13.5in frame) and updated cable routing
This system works extremely well on Trek’s carbon bikes, though we’re yet to ride it on any of the brand's alloy frames — the Domane ALR4 Disc also has the mechanical pivot.
This comfort technology has made it to the Procaliber 8, Procaliber 6 and Procaliber Women’s. All three models are based around the same Alpha Platinum Aluminum frame in Trek’s G2 geometry and utilise the brand's ‘Smart Wheels Size’ system, with the 13.5in and 15.5in frames on 27.5in rolling stock and the larger sizes on 29er hoops.
The new frame also sees Boost hub spacing, a PF92 bottom bracket, 100mm of travel (except for the 13.5in frame, which has an 80mm fork), and updated cable routing to allow for a 31.6mm diameter dropper with stealth routing.
All three builds see a 2x11 Shimano drivetrain, RockShox forks and a fixed seatpost stock and all the Procaliber aluminium frames have a 300lb / 136kg max rider weight.
Procaliber 8
- Frame: Alpha Platinum Alloy
- Fork: RockShox Reba RL, G2 51mm offset, 100mm travel
- Wheels: Bontrager Duster Elite 23, Boost front and rear
- Tyres: Bontrager XR2 Team Issue, tubeless ready, 2.20in
- Drivetrain: Shimano Deore/SLX 11spd w/ Shadow Plus derailleur
- Cranks: Race Face Next R 36/26
- Brakes: Shimano MT500 hydraulic disc
- Bars: Bontrager Race Lite, 720mm width, 5mm rise
- Stem: Bontrager Elite
- Seatpost: Bontrager Pro OCLV Carbon, 31.6mm
- Claimed weight: 11.45 kg / 25.25 lbs 17.5in frame
- £TBC / $2,199 / AU$2,899
Procaliber 6 Women’s
The Women’s Procaliber 6 is almost identical to the Men’s/Unisex bike with the same G2 geometry, but sees slightly narrower bars, a women’s specific saddle and a 13.5in frame size
- Frame: Alpha Platinum Alloy
- Fork: RockShox Recon Gold SL, G2 51mm offset, 100mm travel
- Wheels: Bontrager Duster Elite, Boost front and rear
- Tyres: Bontrager XR2 Team Issue, tubeless ready, 2.20in wide
- Drivetrain: Shimano Deore/SLX 11spd w/ Shadow Plus derailleur
- Cranks: Race Face Aeffect Cranks 36/26
- Brakes: Shimano M425 hydraulic disc
- Bars: Bontrager Alloy, 690mm width, 5mm rise
- Stem: Bontrager Elite, +/- 7-degree
- Seatpost: Bontrager Alloy, 31.6mm diameter
- Claimed weight: 11.43 kg / 25.20 lbs 15.5in frame
- £TBC / $1,889 / AU$2,499
Procaliber 6
- Frame Alpha Platinum Alloy
- Fork: RockShox Recon Gold SL, G2 51mm offset, 100mm travel
- Wheels: Bontrager Duster Elite, Boost front and rear
- Tyres: Bontrager XR2 Team Issue, tubeless ready, 2.20in wide
- Drivetrain: Shimano Deore/SLX 11spd w/ Shadow Plus derailleur
- Cassette: Shimano SLX M7000, 11-42, 11-speed
- Cranks: Race Face Aeffect 36/26
- Brakes: Shimano M425 hydraulic disc
- Bars: Bontrager Alloy, 720mm width, 5mm rise
- Stem: Bontrager Elite, +/- 7-degree
- Seatpost: Bontrager Alloy, 31.6mm diameter
- £TBC / $1,889 / AU$NA
Procaliber frameset
The Procaliber will also be available as a frameset for £TBC / $1,099 / AU$NA and is claimed to weigh 4.4lbs / 2kg in a 17.5in frame.