Transition Sentinel

The Transition Sentinel sits in the sweet spot between playful and planted — nimble enough to pop off lips and thread tight lines, composed enough to hold its own when things get properly rowdy. The option of mixed wheel and full 29" configurations gives riders more control over how it all feels underfoot, and a 24% progressive leverage curve keeps the suspension lively early in the stroke without giving up support when you need it most. B.O.O.M. Box internal storage, updated cable routing, and a geo-adjust flip chip round out a package that feels refined without losing any of what made it a favorite in the first place.

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BIKING TYPE

Trail

WHEEL SIZE

29" (X-Small 27.5")

TRAVEL

160mm Front (150mm Compatible) / 150mm Rear

29" and Mixed Wheel Configurations

The Transition Sentinel comes in a range of wheel sizes to meet rider needs. Size XS is a 27.5, S is mixed, M and L are both dual 29 and mixed, and XL is dual 29. These sizes are tuned to match overall rider size and comfort but can be adjusted based on personal preference.

B.O.O.M Box Storage

In-frame storage for all the essentials and snacks.

Alloy and Carbon Options

The Transition Sentinel comes in both Aluminum Alloy and Carbon options, so you can rip at any price point!

Sentinel Build Kits

Build	Alloy Deore	Alloy Eagle 70	Carbon Eagle 90	Carbon XT	Carbon XT Di2
Frame	Sentinel Alloy 150mm	Sentinel Alloy 150mm	Sentinel Carbon 150mm	Sentinel Carbon 150mm	Sentinel Carbon 150mm
Fork	RockShox Psylo Gold RC	RockShox Psylo Gold RC	RockShox Lyrik Ultimate	RockShox Lyrik Ultimate	Fox 36 Factory Grip X2
Shock	RockShox SuperDeluxe Base	RockShox SuperDeluxe Base	RockShox Super Deluxe Ultimate	RockShox Super Deluxe Ultimate	Fox Float X2 Factory
Drivetrain	Shimano Deore 12sp	SRAM Eagle 70	SRAM Eagle 90	Shimano XT 12sp	Shimano XT Di2
Brakes	Shimano Deore M6120 4-Piston	SRAM Maven Base	SRAM Maven Silver	Shimano XT M8220 4-Piston	Shimano XT M8220 4-Piston
Rims	WTB ST i30	WTB ST i30	DT Swiss M 1900 Spline 30	DT Swiss XM 1700 Spline 30	DT Swiss XM 1700 Spline 30
Cost	$	$$	$$$	$$$$	$$$$$
	Shop	Shop	Shop	Shop	Shop

Sentinel FAQs

Who is the Transition Sentinel for?

The Sentinel V3 is for riders who want one aggressive, capable trail bike that handles everything from all-day pedal missions to seriously gnarly descents without feeling like a compromise in either direction.

With 150mm of rear travel and a 160mm fork on a full 29" platform (with a flip chip to convert to mixed wheels if you prefer), the Sentinel V3 sits at the sweet spot of Transition's lineup. It's built on Transition's well-proven Speed Balanced Geometry; slack enough to inspire confidence on steep and rough terrain, but lively and efficient enough that you won't be dragging yourself up climbs. The V3 geometry was tuned to ride higher in its travel, giving it a sportier, more energetic feel without sacrificing capability when trails get demanding.

It suits a wide range of riders: those looking for a capable daily driver that never holds them back when the trail turns serious, or riders ready to step into a more gravity-oriented bike without giving up the ability to pedal there under their own power.

What's New with The Transition Sentinel? how Is It Different from The V2?

The Sentinel V3 is a more refined, well-rounded version of an already excellent bike. Transition made targeted updates to geometry, suspension, and features that add up to a meaningfully better ride on both ends of the trail.

The most impactful change is the suspension. The V3 runs a higher starting leverage rate, which means bike rides are more supportive and lively earlier in the travel. This makes it snappier and more efficient on mellower terrain and rolling trails, while still having plenty of travel in reserve for big hits.

Geometry also saw a few key tweaks: a slightly steeper head tube angle (64° vs. 63.6°), longer chainstays, and a steeper seat tube angle. The net effect is a more centered, balanced riding position which translates to better weighting on steep climbs and a more planted feel at speed. Transition also added mixed-wheel compatibility via a flip chip at the lower shock mount, along with B.O.O.M. Box in-frame storage on carbon models, reworked cable routing, a new chain slap protector, and size-specific chainstay lengths across the full range.

What's the Difference Between the Transition Sentinel and The Smuggler?

The Smuggler runs 130mm of rear travel with a 140mm fork on full 29" wheels, while the Sentinel V3 bumps to 150mm rear and 160mm front. The Sentinel’s extra travel translates to more confidence on technical, rough descents. The Smuggler, by contrast, is the livelier, more efficient climber. It accelerates quickly and thrives on flowy, moderate singletrack where its shorter travel is never a limitation.

If your trails lean toward punchy, fun singletrack and you value efficiency and speed, the Smuggler delivers. If your rides regularly include consequential descents or you simply want more bike under you when things get loose and steep, the Sentinel V3 is the better fit. Both bikes share the same approachable, confidence-inspiring character that Transition is known for.

What's the Difference Between the Transition Sentinel and The Spire?

The Sentinel V3 is the versatile all-rounder; while the Spire is Transition's most committed gravity bike, built for riders who want maximum capability when they’re pedaling up to go down.

The Spire runs 170mm of travel at both ends on full 29" wheels, making it burlier, heavier, and more planted at speed than the Sentinel V3. On steep, rough descents and enduro-style terrain, the Spire is deeply confidence-inspiring and hard to rattle. The tradeoff is that all that travel and weight add up on climbs.

The Sentinel V3 climbs more efficiently and feels more agile in tight terrain and technical switchbacks. It's a versatile choice for mixed-terrain days. Both bikes share a very similar ride character, but the Sentinel's shorter wheelbase and lighter weight keep it more playful in quick transitions in a way the Spire isn't. If most of your rides involve earning the descent with a real climb, the Sentinel V3 is the more natural fit.

What Are the Key Differences Between the Transition Sentinel Build Kits?

All Sentinel V3 builds share the same frame geometry and GiddyUp suspension platform. The key differences as you move up the lineup are frame material, drivetrain quality, suspension performance, and whether you get Transition's B.O.O.M. Box in-frame storage.

The Alloy Deore is the entry point, an aluminum frame with Shimano Deore drivetrain and brakes, and RockShox suspension. It's a solid, no-frills package that delivers the full Sentinel ride at the most accessible point in the range. Moving to carbon, the 2026 Carbon Eagle 90 pairs the lighter, stiffer carbon frame with SRAM Eagle 90 Transmission for more precise shifting performance. Carbon frames also gain the B.O.O.M. Box in-frame storage. The top-of-the-range 2025 Carbon XT adds Shimano XT drivetrain and brakes with RockShox Ultimate-spec suspension, a Lyrik Ultimate fork with the Charger 3.1 damper and Super Deluxe Ultimate rear shock. This build has a noticeably more refined and capable ride feel, particularly on technical and rough terrain.