Quiver

2018 Specialized Stumpjumper 29/6Fattie vs 2020 Specialized Stumpjumper ST Alloy 29

The Specialized Stumpjumper ST Alloy 29 size closest to your M is the S. Compare the S instead

What changes on the Specialized Stumpjumper ST Alloy 29

Compared with the Specialized Stumpjumper 29/6Fattie in M, the Specialized Stumpjumper ST Alloy 29 in L places the top of the head tube 24 mm higher and 32 mm further forward, relative to the bottom bracket. Its wheelbase is 52 mm longer, which can contribute to stability at speed.

Frame stack
+24 mm
Higher front end
Frame reach
+32 mm
Longer frame reach
Wheelbase
+52 mm
Longer: steadier at speed
Head angle
−0.5°
Slacker: calmer steering
Chainstays
±0 mm
About the same

The two frames

2018 Specialized Stumpjumper 29/6Fattie (M) and 2020 Specialized Stumpjumper ST Alloy 29 (L), lined up at the bottom bracketBoth frames drawn to scale. The Specialized Stumpjumper 29/6Fattie is drawn in full with its measurements, and the Specialized Stumpjumper ST Alloy 29 is the colored outline on top.J 1149

Specialized Stumpjumper 29/6Fattie, MSpecialized Stumpjumper ST Alloy 29, LDrawn to scale and lined up at the bottom bracket.

Geometry side by side

MeasurementSpecialized Stumpjumper 29/6Fattie MSpecialized Stumpjumper ST Alloy 29 LDifference
Reach413mm445mm+32 mm
Stack618mm642mm+24 mm
Head tube angle67°66.5°−0.5°
Seat tube angle74°74.1°+0.1°
Effective top tube590mmnot listed
Chainstay length437mm437mm±0 mm
Wheelbase1149mm1201mm+52 mm
BB drop33mm33mm±0 mm
BB height338mm341mm+3 mm
Standover761mm775mm+14 mm
Seat tube length430mm455mm+25 mm
Fork length560mm560mm±0 mm
Head tube lengthnot listed125mm

Differences are the Specialized Stumpjumper ST Alloy 29 minus the Specialized Stumpjumper 29/6Fattie. Full charts: 2018 Specialized Stumpjumper 29/6Fattie, 2020 Specialized Stumpjumper ST Alloy 29.

Where each sits in its class

Specialized Stumpjumper 29/6FattieSpecialized Stumpjumper ST Alloy 29

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

Each bike is ranked against the other trail 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 Stumpjumper 29/6FattieS-Works 29/6FattieSpecialized Stumpjumper ST Alloy 29
ForkÖhlins RXF 36not listed
Rear shockÖhlins STXnot listed
ShifterSRAM XX1 Eaglenot listed
DerailleurSRAM XX1 Eaglenot listed
CassetteSRAM X01 Eaglenot listed
ChainSRAM XX1 Eaglenot listed
CranksetSRAM XX1 Eaglenot listed
TireSpecialized Butcher, Specialized Purgatorynot listed
HubRoval Traverse SLnot listed
RimRoval Traverse SL 29not listed
BrakeSRAM Guide RSnot listed
StemSyntace F109not listed
GripsSpecialized Sip Gripnot listed
SeatpostSpecialized Command Post IRccnot listed
SaddleSpecialized Henge Expertnot listed

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