Both are excellent climbers, but they get there differently.

The Revel Rascal uses CBF suspension that holds anti-squat above 100% through most of its travel — reviewers consistently describe pedaling it with the climb switch open as the default, and several testers ran 30–35% sag without giving up climbing efficiency. It feels firm and direct under pedaling, almost hardtail-like.

The Stumpjumper 15 runs a quoted ~105–108% anti-squat at sag and uses the GENIE shock's supple initial stroke to maintain ground contact on chunky climbs. Specialized claims a 57% traction gain over the prior generation. The trade-off: it can feel slightly less firm than the Rascal under smooth, hard pedaling, which is what the two-position climb switch is for.

For smoother fire-road climbs, the Rascal feels more efficient. For root-and-rock technical climbs, the Stumpjumper's grip is the bigger weapon.

The Stumpjumper 15, by a clear margin. With 145 mm rear / 150 mm front travel, a 64.5° head angle (adjustable to 63°), and the GENIE shock's progressive end-stroke, it's a bike that genuinely handles bike-park-sized hits. Reviewers note it stays composed on terrain where the Rascal starts to feel overmatched.

The Rascal is a 130/140 mm trail bike with a 65.5° head angle and a relatively short 1,198 mm wheelbase in size Medium. On steep, fast, chunky descents, multiple reviewers describe it as twitchy and demanding precise line choice — it's a bike that rewards finesse, not brute force.

Revel Rascal: not adjustable. Fixed 65.5° head angle, fixed 436 mm chainstays across all sizes, no flip chips.

Specialized Stumpjumper 15: highly adjustable. Headset cups give you 63° / 64.5° / 65.5° head angle; a flip chip adjusts BB height and chainstay length; the frame is mullet-compatible with an aftermarket link; and the fork can be run up to 160 mm. Chainstays are also size-specific from the factory (430 mm on S1 to 445 mm on S5/S6).

The GENIE is a Fox Float with one extra air chamber and one extra seal. Specialized has confirmed it uses mostly standard Fox internals, and most independent suspension shops can service it the same way they'd service any Fox Float — there's just one additional seal in the kit.

That said, it is proprietary, and that raises legitimate long-term concerns: future parts availability, second-owner upgradability, and resale of a non-standard shock. The frame uses a 210x55 mm shock, so you can swap to a standard non-GENIE shock if you ever want to — though the kinematics are tuned around the GENIE's specific air-spring curve, so it won't be a drop-in match.

As of this writing, Revel Bikes appears to have ceased operations. Multiple reviewers covering the Rascal V2 in late 2024 and early 2025 confirmed the news, with speculation that Canfield (the suspension licensor) might support existing owners.

For a buyer, the practical implications are:

- Liquidation pricing on remaining inventory may be excellent.
- Frame warranty and proprietary-part replacement (linkages, bearings, hardware) are uncertain going forward.
- Most non-proprietary parts (suspension, drivetrain, cockpit) are aftermarket-serviceable as normal.

If you can buy at a discount and accept the support risk, the bike itself remains very good. If long-term warranty matters, that's a real point in the Stumpjumper's favor — Specialized backs the frame and pivot bearings for the original owner's lifetime.

Revel Rascal: Small, Medium, Large, XL, XXL. Reach runs 431 mm (S) to 528 mm (XXL); riders roughly 5'1" to 6'8" are covered.

Specialized Stumpjumper 15: S1 through S6. Reach runs 400 mm (S1) to 530 mm (S6); also covers riders from roughly 5'0" to 6'7". Specialized's S-sizing is intentionally overlapping — most riders fit two adjacent sizes, and the choice between them sets ride character (shorter S = playful, longer S = stable).

Revel Rascal: clears up to roughly 29 x 2.5" — Revel quotes 61 mm of chainstay clearance. Stock builds run a 29 x 2.4" Maxxis Dissector front and rear.

Specialized Stumpjumper 15: Specialized doesn't publish a hard clearance number, but the frame ships with 29 x 2.3" Butcher / Eliminator combos and is widely run with 2.4" tires. Larger sizes (S3–S6) run 29" rear out of the box; smaller sizes (S1–S2) run 27.5" rear by default.

Neither is a clearance limitation in practice — both sit firmly in 2.4–2.5" trail-tire territory.

Historically, Specialized holds resale strongly thanks to brand recognition, dealer support, and the lifetime frame warranty (which transfers in spirit through the Specialized network even if not formally to second owners). Stumpjumper variants, especially carbon, are some of the most liquid trail bikes on the used market.

Revel has historically held value reasonably well as a boutique brand, but the recent operations cessation introduces real downside risk for resale — buyers will discount for warranty uncertainty and proprietary-part risk. Expect that to compress used Rascal pricing in the near term, which is bad for sellers and potentially good for buyers who don't mind the support uncertainty.