Quiver

2025 Giant Fathom 29 vs 2025 Giant Fathom

The Giant Fathom size closest to your M is the M. Compare the M instead

What changes on the Giant Fathom

Compared with the Giant Fathom 29 in M, the Giant Fathom in S places the top of the head tube at about the same height and 20 mm further back, relative to the bottom bracket. Its wheelbase is 20 mm shorter, which can contribute to quicker direction changes.

Frame stack
±0 mm
About the same height
Frame reach
−20 mm
Shorter frame reach
Wheelbase
−20 mm
Shorter: quicker to change direction
Head angle
±0.0°
About the same head angle
Chainstays
n/a
One of the bikes has no number for this

The two frames

We can't draw these frames yet. The Giant Fathom 29 numbers we have for size M are missing the chainstay length. The numbers below still compare.

Geometry side by side

MeasurementGiant Fathom 29 MGiant Fathom SDifference
Reach445425−20 mm
Stack622622±0 mm
Head tube angle6666±0.0°
Seat tube angle7575±0.0°
Effective top tube612not listed
Wheelbase11771157−20 mm
BB height314not listed
Standover746not listed
Seat tube length430380−50 mm

Differences are the Giant Fathom minus the Giant Fathom 29. Full charts: 2025 Giant Fathom 29, 2025 Giant Fathom.

Where each sits in its class

Giant Fathom 29Giant Fathom

AggressivePositionUpright
CalmSteeringQuick

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.

PartGiant Fathom 29Fathom 29Giant Fathom1
FrameGiant Fathom 29Giant Fathom
ForkGiant STL 34Giant Crest 34
ShifterShimano CUES SL-6000SRAM SX Eagle
DerailleurShimano CUES U6000SRAM NX Eagle SX
CassetteShimano CS-LG300SRAM PG-1150 SX
ChainKMC X11SRAM SX Eagle
CranksetShimano CUES U6000SRAM SX Eagle Powerspline
ChainringShimano CUES U6030SRAM SX Eagle
WheelsetGiant AM 29Giant AM
TireMaxxis Minion DHF, Maxxis AggressorMaxxis Ardent Race
BrakeShimano MT420Shimano MT420, Shimano MT410
RotorShimano RT-26Shimano RT-26
HandlebarGiant Contact SL TR35Giant Contact SL TR35
StemGiant Contact SL 35Giant Contact SL
GripsGiant Sole-Onot listed
Dropper postGiant Contact Switch ATGiant Contact Switch
SaddleGiant RomeroGiant Romero
Bottom bracketnot listedSRAM DUB GX

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