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Gen 1 Supercaliber/eCaliber Fox IsoStrut, Small Frame, 235mm x 32.5mm,Remote PTL

SKU: 

617395139705

$139.95 $329.95
by Fox
Type: Rear Shocks

Detailed Specifications:

  • Brand: Fox Racing Shox

  • Model: FLOAT IsoStrut Performance Series A Remote PTL (Push-to-Lock)

  • Series: 2021 Performance Series — Black Anodized Finish

  • Part Number: 972-61-257

  • Example Serial Number: 1012985-0030-T (example only – may differ per unit)

  • Frame Compatibility: Trek Supercaliber and eCaliber Gen 1 (Small frames only)

  • Shock Length: 235 mm (Strut length)

  • Damper Length: 135 mm

  • Stroke / Travel: 32.5 mm

  • Outer Diameter: 36 mm

  • Rotation / Eyelet Angle: 60° (specific to Small frame geometry)

  • Spacer Configuration: 0.1 Spacer

  • Damper Type: Performance Series FLOAT IsoStrut Air Spring with Remote PTL Lockout

  • Adjustments: External Rebound / 2-Position Remote Compression (Open / Lock)

  • Axle Configuration: Proprietary Trek IsoStrut mount system (non-standard eye-to-eye)

  • Material: Forged aluminum body, black anodized finish with hard-anodized stanchion

  • Intended Use: XC Race / Marathon / Light Trail

Additional Features:

  • Performance Series tuning: Same internals as Factory Series but with a durable black-anodized finish (no Kashima coating) for maximum reliability.

  • FLOAT air spring system offers tunable progression and excellent small-bump compliance.

  • Remote PTL lockout enables rapid transitions between full-open and firm lock for climbing or sprinting.

  • Integrated IsoStrut design mounts directly into the frame’s top tube for increased lateral stiffness and power transfer.

  • Factory-valved specifically for Trek Supercaliber/eCaliber Gen 1 geometry to deliver balanced rear-end response.

  • Performance-grade wiper seals and bushings for improved durability in mud and dust.

  • Serviceable through any authorized Trek or Fox service center.

Important Usage Notes:

  • Fits Trek Supercaliber and eCaliber Gen 1 (Small) frames only.

  • 60° rotation/eyelet orientation is specific to Small frames — not interchangeable with M/L sizes.

  • Requires a Fox Remote Lockout Lever and cable (sold separately) for function.

  • Not compatible with Gen 2 Supercaliber or any standard eye-to-eye rear shock.

  • Installation must be performed by a qualified Trek or Fox technician to maintain alignment and warranty coverage.

Riding Impressions:

The Fox FLOAT IsoStrut Performance Series transforms the Supercaliber/eCaliber Gen 1 platform into a race-tuned XC machine. Riders benefit from the FLOAT air spring’s smooth stroke and the Performance Series’ durable finish, ideal for dusty race courses and all-season training. The remote lockout delivers instant pedaling efficiency while the integrated strut layout preserves Trek’s signature rigid-frame feel with controlled traction.