Trek Session Frame
Lifecycle status:
- Session 8 (29) (2022): The catalog records this variant as discontinued. No recorded successor.
What the checker says504will not fit13check before you buy764worth knowing
Run variant by variant through the mountain bike builder’s own engine. Every sentence below is the checker’s, unedited. Nothing here says this part fits your bike; it says what it does and does not fit among the parts we hold.
Checked against 5916 verified mountain bike parts in this catalog. 2895 produced no finding of any kind; that is Session C 29 (2022). Session 8 (29) (2022) clears 2887. Each variant produces 218 to 309 distinct errors and 7 to 8 distinct warnings.
Will not fit
- Will not fiterror · Rear ShockShock mount mismatch: Frame uses a Trunnion shock but Shock is Standard eyelet. On 529 of the 1025 verified rear shocks in this catalog. Applies to 1 of 2 variants.
- Will not fiterror · Rear ShockShock mount mismatch: Frame uses a Standard eyelet shock but Shock is Trunnion. On 496 of the 1025 verified rear shocks in this catalog. Applies to 1 of 2 variants.
- Will not fiterror · ForkSteerer mismatch: Fork is Tapered (1.5-1.125) but Frame headset is Straight 1.125 (dual-crown). On 429 of the 490 verified forks in this catalog. Applies to all 2 variants.
- Will not fiterror · Rear WheelRear axle mismatch: Frame is SuperBoost 157x12 but Rear wheel hub is Boost 148x12. On 410 of the 607 verified rear wheels in this catalog. Applies to all 2 variants.
- Will not fiterror · Rear WheelUnsupported wheel setup: Trek Session 8 (29) supports 29", but this build is front (any) / rear 27.5". On 239 of the 607 verified rear wheels in this catalog. Applies to 1 of 2 variants.
- Will not fiterror · Rear WheelUnsupported wheel setup: Trek Session C 29 supports 29", but this build is front (any) / rear 27.5". On 239 of the 607 verified rear wheels in this catalog. Applies to 1 of 2 variants.
Bb shell, Bottom Bracket. 116 more findings from the same check, on up to 1 of the 63 verified bottom brackets each.
Shock size, Rear Shock. 103 more findings from the same check, on up to 57 of the 1025 verified rear shocks each.
Shock stroke over, Rear Shock. 81 more findings from the same check, on up to 1 of the 1025 verified rear shocks each.
Headset upper, Headset. 67 more findings from the same check, on up to 1 of the 70 verified headsets each.
Headset lower, Headset. 44 more findings from the same check, on up to 1 of the 70 verified headsets each.
Gearbox frame, Gearbox. 12 more findings from the same check, on up to 1 of the 6 verified gearboxs each.
Rear brake mount, Rear Brake. 12 more findings from the same check, on up to 1 of the 92 verified brakes each.
Wheel config, Front Rim. 6 more findings from the same check, on up to 33 of the 75 verified rims each.
Wheel config, Front Tire. 6 more findings from the same check, on up to 223 of the 617 verified tires each.
Wheel config, Front Wheel. 6 more findings from the same check, on up to 90 of the 270 verified front wheels each.
Wheel config, Rear Tire. 6 more findings from the same check, on up to 223 of the 617 verified tires each.
Oem shock, Rear Shock. 5 more findings from the same check, on up to 1 of the 1025 verified rear shocks each.
Rear axle, Rear Hub. 5 more findings from the same check, on up to 5 of the 124 verified rear hubs each.
Shock stroke short, Rear Shock. 4 more findings from the same check, on up to 24 of the 1025 verified rear shocks each.
Wheel config, Fork. 4 more findings from the same check, on up to 157 of the 490 verified forks each.
Wheel config, Rear Rim. 4 more findings from the same check, on up to 3 of the 75 verified rims each.
Wheel config, Rear Wheel. 4 more findings from the same check, on up to 7 of the 607 verified rear wheels each.
Rear axle, Rear Wheel. 3 more findings from the same check, on up to 27 of the 607 verified rear wheels each.
Seatpost diameter small, Seatpost (rigid). 3 more findings from the same check, on up to 22 of the 70 verified seatpost (rigid)s each.
Dropper diameter small, Dropper Post. 2 more findings from the same check, on up to 119 of the 350 verified dropper posts each.
Dropper diameter, Dropper Post. 1 more finding from the same check, on up to 72 of the 350 verified dropper posts each.
Seatpost diameter, Seatpost (rigid). 1 more finding from the same check, on up to 4 of the 70 verified seatpost (rigid)s each.
Open a variant in the builder to see the ones that apply to your own parts.
Check before you buy
- Check before you buywarning · Rear TireRear tire clearance: 2.6in tire is wider than Trek Session C 29's 2.5in frame max. On 108 of the 617 verified tires in this catalog. Applies to 1 of 2 variants.
- Check before you buywarning · Rear TireRear tire clearance: 2.8in tire is wider than Trek Session 8 (29)'s 2.6in frame max. On 15 of the 617 verified tires in this catalog. Applies to 1 of 2 variants.
- Check before you buywarning · Rear TireRear tire clearance: 2.8in tire is wider than Trek Session C 29's 2.5in frame max. On 15 of the 617 verified tires in this catalog. Applies to 1 of 2 variants.
- Check before you buywarning · ForkSteerer mismatch: Fork is Straight 1.125 (single-crown) but Frame headset is Straight 1.125 (dual-crown). Both are the same straight 1-1/8in steerer, so the headset itself is not the question. Check that this frame is rated for a dual-crown fork (head tube length and total headset stack) before you build it. On 6 of the 490 verified forks in this catalog. Applies to all 2 variants.
- Check before you buywarning · Rear RotorRear rotor: 223mm exceeds the frame max of 220mm. A post-mount adapter is the part that steps a caliper up to a bigger rotor, sold in the maker’s own discrete size steps (commonly +20mm, e.g. 160 to 180mm or 180 to 200mm) rather than for any gap - and not every step is offered for every caliper model, so check the maker’s own fitment before buying. On 5 of the 177 verified rotors in this catalog. Applies to all 2 variants.
- Check before you buywarning · Rear TireRear tire clearance: 3in tire is wider than Trek Session 8 (29)'s 2.6in frame max. On 5 of the 617 verified tires in this catalog. Applies to 1 of 2 variants.
- Check before you buywarning · Rear TireRear tire clearance: 3in tire is wider than Trek Session C 29's 2.5in frame max. On 5 of the 617 verified tires in this catalog. Applies to 1 of 2 variants.
Rear tire frame, Rear Tire. 6 more findings from the same check, on up to 1 of the 617 verified tires each.
Open a variant in the builder to see the ones that apply to your own parts.
Worth knowing
- Worth knowinginfo · ForkHeadset: Trek Session 8 (29) takes ZS49 upper / ZS56 lower cups (S.H.I.S.) to mount the fork - many frames ship with one; pick one here if yours does not. On 490 of the 490 verified forks in this catalog. Applies to 1 of 2 variants.
- Worth knowinginfo · Dropper PostLong-drop post: the BikeYoke Divine 2.0 (185mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Trek Session 8 (29) frame size. On 3 of the 350 verified dropper posts in this catalog. Applies to 1 of 2 variants.
- Worth knowinginfo · Dropper PostLong-drop post: the BikeYoke Divine 2.0 (185mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Trek Session C 29 frame size. On 3 of the 350 verified dropper posts in this catalog. Applies to 1 of 2 variants.
- Worth knowinginfo · Dropper PostLong-drop post: the BikeYoke Divine 2.0 (213mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Trek Session 8 (29) frame size. On 3 of the 350 verified dropper posts in this catalog. Applies to 1 of 2 variants.
- Worth knowinginfo · Dropper PostLong-drop post: the BikeYoke Divine 2.0 (213mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Trek Session C 29 frame size. On 3 of the 350 verified dropper posts in this catalog. Applies to 1 of 2 variants.
- Worth knowinginfo · ForkHeadset: mounting the RockShox 35 Gold RL in Trek Session C 29 needs a headset - many frames ship with one; pick one here if yours does not. On 3 of the 490 verified forks in this catalog. Applies to 1 of 2 variants.
Headset advisory, Fork. 485 more findings from the same check, on up to 2 of the 490 verified forks each.
Dropper insertion, Dropper Post. 176 more findings from the same check, on up to 1 of the 350 verified dropper posts each.
Bb advisory, Crankset. 97 more findings from the same check, on up to 2 of the 98 verified cranksets each.
Open a variant in the builder to see the ones that apply to your own parts.
$2,999.00 to $4,199.00 MSRP·3240 to 4200 g
What the maker states
- Wheel configs
- Frame takes 29" wheels
- Travel
- Frame travel 200 mm (maker-stated)
- Shock eye
- Shock eye-to-eye 225 mm (on 1 of 2 variants); Shock eye-to-eye 250 mm (on 1 of 2 variants)
- Shock stroke
- 70 mm (on 1 of 2 variants); 72.5 mm (on 1 of 2 variants)
- Shock mount
- Standard eyelet (on 1 of 2 variants); Trunnion (on 1 of 2 variants)
- Maximum fork travel
- Approved for a fork up to 203 mm of travel
A value shown as a set or a range differs between this model’s variants and is never one variant’s spec.
2 verified variants
| Variant | Shock eye | Shock stroke | Shock mount | Price (MSRP) | Weight | Source | Last checked | Build |
|---|---|---|---|---|---|---|---|---|
| Session 8 (29) (2022) | Shock eye-to-eye 250 mm | 72.5 mm | Standard eyelet | $2,999.00 | 4200 g | maker’s page | 2026-08-02 | Build with this |
| Session C 29 (2022) | Shock eye-to-eye 225 mm | 70 mm | Trunnion | $4,199.00 | 3240 g | maker’s page | 2026-07-17 | Build with this |
The rest of what the maker states13 stated·23 not published
- Rear axle SuperBoost 157x12.
- Bottom-bracket shell BSA threaded 83 (DH).
- Upper head-tube bore ZS49/28.6 (S.H.I.S.) (on 1 of 2 variants).
- Lower head-tube bore ZS56/40 (S.H.I.S.) (on 1 of 2 variants).
- Seatpost diameter 31.6 mm.
- Rear rotor up to 220 mm (maker-stated maximum).
- Tire up to 2.5" (maker-stated maximum) (on 1 of 2 variants); Tire up to 2.6" (maker-stated maximum) (on 1 of 2 variants).
- SRAM Universal Derailleur Hanger.
- Fits a Straight 1.125 (dual-crown) head tube.
- Brake mount Post mount.
- Full-suspension frame.
- Sold as a frameset, not a bare frame.
- Aluminum construction (on 1 of 2 variants); Carbon construction (on 1 of 2 variants).
23 further fields the checker looks for are not published by Trek, so we leave them blank rather than estimate them, and those 23 checks stay silent on this frame. They are minimum rear rotor, alt shock strokes, shock stroke by size, travel by stroke, minimum fork travel, design fork travel, fork travel hard, coil approved, drive mode, dropout type, gearbox mount, belt drive, udh unstated, udh retrofit kit, maximum tire mm, maximum tire basis, maximum tire by wheel, head tube upper alts, head tube lower alts, headset included, headset included model, headset included part and maker shocks. Each is recorded as “not stated by the maker (not checked)”.
Source: each variant links the maker’s own page in the table above. Last checked 2026-07-17 to 2026-08-02.
Checked against
The checker ran this model against every verified part below that it has a slot for, the same way it checks a build in the builder. What follows is the verdict it actually produced for that specific pairing — not a recommendation, and not a guarantee any of these parts fits your own bike.
- 5DEV R-SPEC Trail/Enduro Cranks (Crankset) Worth knowing
- 9point8 Fall Line (Dropper Post) Will not fit
- 9point8 Stout (31.8, 30mm) (Stem) No conflicts found
- ACID SLX 30 front (Front Wheel) No conflicts found
- ACID SLX 30 rear (Rear Wheel) Will not fit
- Acros ZS44/ZS56 (Headset) Will not fit
6 of 1701 counterparts with a page of their own that the checker actually probed this model against, in alphabetical order by brand and model — never by price, popularity or the verdict itself.