Quiver

2026 Surly Preamble Flat Bar vs 2026 3T Primo

The 3T Primo size closest to your M is the L. Compare the L instead

What changes on the 3T Primo

Compared with the Surly Preamble Flat Bar in M, the 3T Primo in XL places the top of the head tube 37 mm higher and 11 mm further forward, relative to the bottom bracket.

Frame stack
+37 mm
Higher front end
Frame reach
+11 mm
Longer frame reach
Wheelbase
n/a
One of the bikes has no number for this
Head angle
+0.5°
Steeper: sharper steering
Chainstays
n/a
One of the bikes has no number for this

The two frames

2026 Surly Preamble Flat Bar (M)The Surly Preamble Flat Bar frame drawn to scale.J 1030

Only the Surly Preamble Flat Bar is drawn. The 3T Primo numbers we have for size XL are missing the chainstay length and wheelbase.

Geometry side by side

MeasurementSurly Preamble Flat Bar M3T Primo XLDifference
Reach391402+11 mm
Stack567604+37 mm
Head tube angle7272.5+0.5°
Seat tube angle72.572.5±0.0°
Effective top tube570592+22 mm
Chainstay length435not listed
Wheelbase1030not listed
BB drop6670+4 mm
Standover826not listed
Seat tube length565not listed
Fork length400not listed
Head tube length130180+50 mm

Differences are the 3T Primo minus the Surly Preamble Flat Bar. Full charts: 2026 Surly Preamble Flat Bar, 2026 3T Primo.

Where each sits in its class

Surly Preamble Flat Bar3T Primo

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

Each bike is ranked against the other gravel 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.

PartSurly Preamble Flat BarFlat Bar3T PrimoGRX 1X12
FrameSurly Preamble3T Primo2
ShiftermicroSHIFT Acolyte XpressShimano GRX RX610
DerailleurmicroSHIFT RD-M5185MShimano GRX RX822 SGS
ChainKMC Z8.3not listed
TireKenda Kwik TendrilPirelli Cinturato Adventure
BrakeAvid BB5Shimano GRX RX400
SaddleSelle Italia Xfizik Vento Argo X5
Forknot listed3T Fango Primo2
Cassettenot listedShimano Deore M6100
Cranksetnot listedShimano GRX RX610
Wheelsetnot listedFulcrum Rapid Red 900
Rotornot listedShimano SM-RT64
Handlebarnot listed3T Superergo PRO
Stemnot listed3T Apto
Seatpostnot listed3T Primo

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