Quiver

2027 Trek Fuel EX 9.8 Gen 7 vs 2025 YT Jeffsy CORE

The XXL is the YT Jeffsy CORE size closest to your XL Trek Fuel EX 9.8 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 9.8 Gen 7 in XL, the YT Jeffsy CORE in XXL places the top of the head tube 9 mm lower and 5 mm further forward, relative to the bottom bracket. Its wheelbase is 9 mm shorter, which can contribute to quicker direction changes.

Frame stack
−9 mm
Lower front end
Frame reach
+5 mm
Longer frame reach
Wheelbase
−9 mm
Shorter: quicker to change direction
Head angle
+0.5°
Steeper: sharper steering
Chainstays
−5 mm
Shorter: livelier

The two frames

2027 Trek Fuel EX 9.8 Gen 7 (XL) and 2025 YT Jeffsy CORE (XXL), lined up at the bottom bracketBoth frames drawn to scale. The Trek Fuel EX 9.8 Gen 7 is drawn in full with its measurements, and the YT Jeffsy CORE is the colored outline on top.J 1298

Trek Fuel EX 9.8 Gen 7, XLYT Jeffsy CORE, XXLDrawn to scale and lined up at the bottom bracket.

Geometry side by side

MeasurementTrek Fuel EX 9.8 Gen 7 XLYT Jeffsy CORE XXLDifference
Reach510515+5 mm
Stack651642−9 mm
Head tube angle64.5°65+0.5°
Seat tube angle76.9°77.2+0.3°
Effective top tube651not listed
Chainstay length447442−5 mm
Wheelbase12981289−9 mm
BB drop3533−2 mm
BB height339not listed
Standover755not listed
Seat tube length455not listed
Head tube length140not listed

Differences are the YT Jeffsy CORE minus the Trek Fuel EX 9.8 Gen 7. Full charts: 2027 Trek Fuel EX 9.8 Gen 7, 2025 YT Jeffsy CORE.

Where each sits in its class

Trek Fuel EX 9.8 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 9.8 Gen 79.8 Eagle 90 Gen 7YT Jeffsy CORECORE 1
ForkRockShox Lyrik UltimateMarzocchi Bomber Z1
Rear shockRockShox Deluxe RC2T UltimateMarzocchi Bomber Air
DerailleurSRAM Eagle 90 TransmissionShimano Deore
CassetteSRAM GX Eagle TransmissionShimano Deore M6100
ChainSRAM GX Eaglenot listed
CranksetSRAM Eagle 90 TransmissionShimano Deore M512
Bottom bracketSRAM DUBShimano MT501
WheelsetBontrager Line Comp 30Sun Ringlé SR329 Trail Comp
TireMaxxis Minion DHFMaxxis Minion DHF, Maxxis Minion DHR II DD
BrakeSRAM Maven 4-piston BronzeSRAM DB8 Stealth
RotorSRAM HS2not listed
HandlebarRace Face TurbineYT Handlebar 35
GripsTrek Line EliteODI Elite Motion V2.1
SeatpostBontrager Line DropperYT Seatpost
SaddleTrek VerseYT Custom Design
Shifternot listedShimano Deore
Stemnot listedYT Stem 35
Headsetnot listedCane Creek Series 10

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