Quiver

2026 Polygon Siskiu T T7 UDH vs 2025 Trek Fuel EX

The ML is the Trek Fuel EX size closest to your L Polygon Siskiu T T7 UDH. 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 Trek Fuel EX

Compared with the Polygon Siskiu T T7 UDH in L, the Trek Fuel EX in ML places the top of the head tube 5 mm lower and 15 mm further back, relative to the bottom bracket. Its wheelbase is 7 mm shorter, which can contribute to quicker direction changes.

Frame stack
−5 mm
Lower front end
Frame reach
−15 mm
Shorter frame reach
Wheelbase
−7 mm
Shorter: quicker to change direction
Head angle
±0.0°
About the same head angle
Chainstays
+10 mm
Longer: more planted

The two frames

2026 Polygon Siskiu T T7 UDH (L)The Polygon Siskiu T T7 UDH frame drawn to scale.J 1240

Only the Polygon Siskiu T T7 UDH is drawn. The Trek Fuel EX numbers we have for size ML are missing the seat angle.

Geometry side by side

MeasurementPolygon Siskiu T T7 UDH LTrek Fuel EX MLDifference
Reach485470−15 mm
Stack622616.8−5 mm
Head tube angle64.564.5±0.0°
Seat tube angle71.2not listed
Effective top tube619607.4−12 mm
Chainstay length430440+10 mm
Wheelbase12401233.1−7 mm
BB drop3938−1 mm
BB height337.5335−3 mm
Standover713741.8+29 mm
Seat tube length415420+5 mm
Head tube length110100−10 mm

Differences are the Trek Fuel EX minus the Polygon Siskiu T T7 UDH. Full charts: 2026 Polygon Siskiu T T7 UDH, 2025 Trek Fuel EX.

Where each sits in its class

Polygon Siskiu T T7 UDHTrek Fuel EX

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.

PartPolygon Siskiu T T7 UDHT7 with UDHTrek Fuel EX5
FramePolygon ALX TrailTrek Fuel EX
ForkRockShox Recon Silver RLRockShox Recon Silver
Rear shockRockShox Deluxe Select+X-Fusion Pro 2
ShifterShimano Deore M6100Shimano Deore M6100
DerailleurShimano Deore M6100Shimano Deore M6100
CassetteShimano Deore M6100Shimano Deore M6100
ChainKMC New X-12Shimano Deore M6100
CranksetShimano Deore M6120Shimano MT512
ChainringShimano FC-M6120-1not listed
Bottom bracketShimano 2-pieceShimano MT501
WheelsetPolygon MT6Bontrager Line TLR 30
TireMaxxis DissectorBontrager Gunnison Elite XR
BrakeShimano MT420Shimano MT200
RotorShimano SM-RT54Shimano SM-RT56
HandlebarPolygon EXPERTTranzX JD-YSI-22PLQ
StemPolygon EXPERTBontrager Comp
HeadsetFSA No 57Enot listed
SeatpostX-Fusion MANIC LCnot listed
SaddleLinc XTENTBontrager Arvada
Gripsnot listedBontrager XR Trail
Dropper postnot listedTranzX JD-YSI-22PLQ

Know what is on every bike.

Add your bike to Quiver. Keep its parts, setup, and service history together, then share your build.

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