Quiver

2026 Trek Fuel EX 9.9 Gen 7 vs 2025 YT Jeffsy CORE

The S is the YT Jeffsy CORE size closest to your S Trek Fuel EX 9.9 Gen 7. 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 9.9 Gen 7 in S, the YT Jeffsy CORE in S places the top of the head tube 3 mm higher and 4 mm further forward, relative to the bottom bracket. Its wheelbase is 4 mm longer, which can contribute to stability at speed.

Frame stack
+3 mm
Higher front end
Frame reach
+4 mm
Longer frame reach
Wheelbase
+4 mm
Longer: steadier at speed
Head angle
+0.4°
Steeper: sharper steering
Chainstays
±0 mm
About the same

The two frames

2026 Trek Fuel EX 9.9 Gen 7 (S) and 2025 YT Jeffsy CORE (S), lined up at the bottom bracketBoth frames drawn to scale. The Trek Fuel EX 9.9 Gen 7 is drawn in full with its measurements, and the YT Jeffsy CORE is the colored outline on top.J 1187

Trek Fuel EX 9.9 Gen 7, SYT Jeffsy CORE, SDrawn to scale and lined up at the bottom bracket.

Geometry side by side

MeasurementTrek Fuel EX 9.9 Gen 7 SYT Jeffsy CORE SDifference
Reach431435+4 mm
Stack610613+3 mm
Head tube angle64.6°65+0.4°
Seat tube angle78.7°77.2−1.5°
Effective top tube548not listed
Chainstay length437437±0 mm
Wheelbase11871191+4 mm
BB drop3433−1 mm
BB height340not listed
Standover741not listed
Seat tube length370not listed
Head tube length95not listed

Differences are the YT Jeffsy CORE minus the Trek Fuel EX 9.9 Gen 7. Full charts: 2026 Trek Fuel EX 9.9 Gen 7, 2025 YT Jeffsy CORE.

Where each sits in its class

Trek Fuel EX 9.9 Gen 7YT 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 9.9 Gen 79.9 X0 AXS Gen 7YT Jeffsy CORECORE 1
ForkRockShox Lyrik UltimateMarzocchi Bomber Z1
Rear shockRockShox Deluxe RC2T UltimateMarzocchi Bomber Air
ShifterSRAM Pod ControllerShimano Deore
DerailleurSRAM X0 Eagle AXSShimano Deore
CassetteSRAM X0 Eagle TransmissionShimano Deore M6100
ChainSRAM X0 Eaglenot listed
CranksetSRAM X0 EagleShimano Deore M512
BatterySRAM AXSnot listed
WheelsetBontrager Line Pro 30Sun Ringlé SR329 Trail Comp
TireMaxxis Minion DHFMaxxis Minion DHF, Maxxis Minion DHR II DD
BrakeSRAM MavenSRAM DB8 Stealth
RotorSRAM HS2not listed
HandlebarRace Face ERAYT Handlebar 35
StemRace Face TurbineYT Stem 35
GripsTrek Line EliteODI Elite Motion V2.1
SeatpostRockShox Reverb AXSYT Seatpost
SaddleTrek VerseYT Custom Design
Bottom bracketnot listedShimano MT501
Headsetnot listedCane Creek Series 10

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