Quiver

2021 Specialized Rockhopper Expert vs 2019 Trek X-Caliber Frameset

The Trek X-Caliber Frameset size closest to your XS is the XS. Compare the XS instead

What changes on the Trek X-Caliber Frameset

Compared with the Specialized Rockhopper Expert in XS, the Trek X-Caliber Frameset in S places the top of the head tube 16 mm higher and 9 mm further forward, relative to the bottom bracket. Its wheelbase is 13 mm shorter, which can contribute to quicker direction changes.

Frame stack
+16 mm
Higher front end
Frame reach
+9 mm
Longer frame reach
Wheelbase
−13 mm
Shorter: quicker to change direction
Head angle
+1.2°
Steeper: sharper steering
Chainstays
−15 mm
Shorter: livelier

The two frames

2021 Specialized Rockhopper Expert (XS)The Specialized Rockhopper Expert frame drawn to scale.J 1067

Only the Specialized Rockhopper Expert is drawn. The Trek X-Caliber Frameset numbers we have for size S are missing the seat angle.

Geometry side by side

MeasurementSpecialized Rockhopper Expert XSTrek X-Caliber Frameset SDifference
Reach375mm384+9 mm
Stack559mm575+16 mm
Head tube angle68°69.2°+1.2°
Seat tube angle73.5°not listed
Chainstay length440mm425−15 mm
Wheelbase1067mm1054−13 mm
Standover658mm728+70 mm
Seat tube length310mm368+58 mm
Fork length475mmnot listed
Head tube length95mm90−5 mm
Effective top tubenot listed564
BB dropnot listed48
BB heightnot listed306

Differences are the Trek X-Caliber Frameset minus the Specialized Rockhopper Expert. Full charts: 2021 Specialized Rockhopper Expert, 2019 Trek X-Caliber Frameset.

Where each sits in its class

Specialized Rockhopper ExpertTrek X-Caliber Frameset

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

Each bike is ranked against the other XC bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.

What each ships with

The stock build of each bike's first listed trim. Parts that match are dimmed.

PartSpecialized Rockhopper ExpertExpertTrek X-Caliber FramesetX-Caliber Frameset
FrameSpecialized A1 premium buttedTrek Alpha Gold
ForkRockShox Judynot listed
ShifterSRAM SX Eaglenot listed
DerailleurSRAM SX Eaglenot listed
CassetteSRAM SX Eaglenot listed
ChainSRAM SX Eaglenot listed
CranksetSRAM SX Eaglenot listed
Bottom bracketSRAM PowerSplinenot listed
Wheelsete*thirteen SLnot listed
TireSpecialized Ground Controlnot listed
HubShimano HB-RM35, Shimano FH-RM35not listed
RimSpecialized hooklessnot listed
BrakeShimano MT200not listed
RotorShimano MT200not listed
HandlebarSpecialized alloynot listed
StemSpecialized Stoutnot listed
GripsSpecialized Trailnot listed
SaddleSpecialized Bridge Sportnot listed

Know what is on every bike.

Add your bike to Quiver. Keep its parts, setup, and service history together, then share your build.

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