Transition Sentinel Alloy Youth XT

Name: Transition Sentinel Alloy Youth XT
Brand: Transition

2026 YouthMountain youth Manufacturer page

Last known price: $4,599

Prices shown first for United States
Travel: 160 / 150 mm Fork / rear shock
Wheels: 27.5″
Drivetrain: 1 × 12 30t / 10–51t
Gear range: 510%
Weight: 15.58 kg 34.3 lb · Reference configuration not specified
Frame: Aluminum
Brakes: Hydraulic disc

Rider height by size (cm)

Size guide

XS 143–160

Components

18 of 23 identified

Parts found in a manufacturer catalog show their brand, model and key numbers, and the steps show how precisely they are identified: brand, series, model, or the exact product. The info button has every detail and the text the manufacturer published.

Frame and fork

1 part

Frame

Sentinel Alloy 150mm Not identified

Suspension

2 parts

Drivetrain

7 parts

Bottom bracket

73mm BSA Threaded Not identified
Cassette
- Shimano Deore XT CS-M8100 12 speeds 10–51t
CS-M8100
Chain
- Shimano Deore XT CN-M8100
CN-M8100
Chain guide

ISCG05 Not identified
Crankset
- Shimano Deore XT FC-M8100 12 speeds 30t
FC-M8100
Rear derailleur
- Shimano Deore XT RD-M8100-SGS 12 speeds
RD-M8100-SGS
Shifters
- Shimano Deore XT SL-M8100
SL-M8100

Brakes

2 parts

Wheels and tires

5 parts

Cockpit and contact points

6 parts

Grips
- ODI
Handlebar

ANVL Mandrel Alloy 35, (800x20mm) Not identified
Headset
- FSA NO.57E
Saddle
- SDG Bel-Air
Seatpost
- OneUp
Stem

ANVL Swage (40mm) Not identified

Sizes and geometry

1 size Open in the geometry plotter

Enter your height to highlight matching ranges.

Size XS

Table

Reach 415mm

Stack 592mm

Wheelbase 1173mm

Head angle 64.0°

Seat angle 79.5°

Every size is drawn to the same scale, in millimeters. Explanatory schematic on an assumed 27.5″ wheel; exact published values are in the table below.

Size Reported by the manufacturer

Complete manufacturer geometry table 1 published size

Complete manufacturer geometry by size
Measurement
Reachmm	415
Stackmm	592
Top tube lengthmm	527
Seat tube lengthmm	360
Head tube lengthmm	100
Head tube angle	64°
Seat tube angle	79.5°
Chainstay lengthmm	436
Wheelbasemm	1173
Front centermm	737
Bottom bracket dropmm	15
Bottom bracket heightmm	340
Fork rakemm	37
Trailmm	132
Stack/reach ratio	1.43

Not published by the manufacturer: Standover height, Front travel, Rear travel, Crank length, Handlebar width, Stem length, Stem angle, Seatpost length and Dropper post travel.

Specifications

Frame and fork

Intended fit: Unisex
Frame material: Aluminum
Bicycle weight: 15.58 kg

34.3 lb

Suspension

Suspension configuration: Full suspension
Front travel: 160 mm
Rear travel: 150 mm

Drivetrain

Derived by Bikelake

Front chainrings: 1
Smallest chainring: 30
Largest chainring: 30
Rear sprockets: 12
Smallest sprocket: 10
Largest sprocket: 51
Lowest gear: 16.2 in
Highest gear: 82.5 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Seatpost: Dropper seatpost
Shifting: Mechanical

Additional specifications

Bottom bracket standard: BSA
Tire width: 2.5″
Wheel material: Aluminum
Wheel size: 27.5″

Technical analysis

1 measure

How these figures sit among bicycles of the same class and model year. Context, not a ranking.

Shifting

Mechanical

9 of 321 bicycles with this information use electronic shifting.

Cohort: Youth / Mountain youth Model year: 2026
Sample: 321 bicycles with this information
Coverage: 100.0% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 6.2 km/h
Highest gear: 31.6 km/h

Total gear range 510%

Technical details and class reference

These speeds describe the gearing at the selected cadence, not how fast you can ride.
Calculated from published gear-inch values and their wheel-size assumptions.
These gearing values describe the bicycle, not a selected frame size.
A 100% range means one ratio; 500% means the highest ratio is five times the lowest.
For e-bikes, motor assistance cutoff is not represented.

Gear-inch range

Lower gear-inch values travel less distance per pedal revolution; higher values travel farther.

This bicycle: 16.2–82.5 gear inches

Lineup changes

The published facts that differ across this family's builds and from the same model a year earlier. Missing information never counts as zero.

Differences across 2026 builds

Differences across 2026 builds
Specification	This bicycle Transition Sentinel Alloy Youth XT	Transition Sentinel Alloy Eagle 70	Transition Sentinel Alloy Eagle 90	Transition Sentinel Carbon Youth Deore	Transition Sentinel Carbon Eagle 90	Transition Sentinel Carbon Eagle 90 Youth
Frame
Frame material	Aluminum	Aluminum	Aluminum	Carbon	Carbon	Carbon
Bicycle weight	15.58 kg	Not informed	Not informed	15.21 kg	Not informed	Not informed
Drivetrain
Largest sprocket	51	52	52	51	52	52
Lowest gear	16.2 in	16.7 in	16.7 in	16.2 in	16.7 in	15.9 in
Highest gear	82.5 in	87.0 in	87.0 in	82.5 in	87.0 in	82.5 in
Other specifications
Wheel size	27.5″	29″	29″	27.5″	29″	27.5″
Fork spring	Not informed	Not informed	Air	Air	Air	Air