Quiver

2023 Trek Fuel EX AL Gen 6 Frameset vs 2025 YT Jeffsy CORE

The XL is the YT Jeffsy CORE size closest to your L Trek Fuel EX AL Gen 6 Frameset. We match frame stack and reach. This is a geometry comparison, not a fit recommendation; stem, spacers, handlebars and saddle setup also affect your riding position.

What changes on the YT Jeffsy CORE

Compared with the Trek Fuel EX AL Gen 6 Frameset in L, the YT Jeffsy CORE in XL places the top of the head tube 17 mm higher and 4 mm further forward, relative to the bottom bracket. Its wheelbase is 17 mm longer, which can contribute to stability at speed.

Frame stack
+17 mm
Higher front end
Frame reach
+4 mm
Longer frame reach
Wheelbase
+17 mm
Longer: steadier at speed
Head angle
−0.1°
About the same head angle
Chainstays
+4 mm
Longer: more planted

The two frames

2023 Trek Fuel EX AL Gen 6 Frameset (L) and 2025 YT Jeffsy CORE (XL), lined up at the bottom bracketBoth frames drawn to scale. The Trek Fuel EX AL Gen 6 Frameset is drawn in full with its measurements, and the YT Jeffsy CORE is the colored outline on top.J 1249

Trek Fuel EX AL Gen 6 Frameset, LYT Jeffsy CORE, XLDrawn to scale and lined up at the bottom bracket.

Geometry side by side

MeasurementTrek Fuel EX AL Gen 6 Frameset LYT Jeffsy CORE XLDifference
Reach491495+4 mm
Stack617634+17 mm
Head tube angle65.1°65−0.1°
Seat tube angle77.7°77.2−0.5°
Effective top tube626not listed
Chainstay length438442+4 mm
Wheelbase12491266+17 mm
BB drop3133+2 mm
BB height343not listed
Standover754not listed
Seat tube length435not listed
Head tube length105not listed

Differences are the YT Jeffsy CORE minus the Trek Fuel EX AL Gen 6 Frameset. Full charts: 2023 Trek Fuel EX AL Gen 6 Frameset, 2025 YT Jeffsy CORE.

Where each sits in its class

Trek Fuel EX AL Gen 6 FramesetYT Jeffsy CORE

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.

PartTrek Fuel EX AL Gen 6 FramesetYT Jeffsy CORECORE 1
Forknot listedMarzocchi Bomber Z1
Rear shocknot listedMarzocchi Bomber Air
Shifternot listedShimano Deore
Derailleurnot listedShimano Deore
Cassettenot listedShimano Deore M6100
Cranksetnot listedShimano Deore M512
Bottom bracketnot listedShimano MT501
Wheelsetnot listedSun Ringlé SR329 Trail Comp
Tirenot listedMaxxis Minion DHF, Maxxis Minion DHR II DD
Brakenot listedSRAM DB8 Stealth
Handlebarnot listedYT Handlebar 35
Stemnot listedYT Stem 35
Gripsnot listedODI Elite Motion V2.1
Headsetnot listedCane Creek Series 10
Seatpostnot listedYT Seatpost
Saddlenot listedYT Custom Design

Know what is on every bike.

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