Quiver

2026 Polygon Siskiu T T6 UDH vs 2025 Trek Fuel EX

The ML is the Trek Fuel EX size closest to your M Polygon Siskiu T T6 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 T6 UDH in M, the Trek Fuel EX in ML places the top of the head tube 8 mm higher and 5 mm further forward, relative to the bottom bracket. Its wheelbase is 19 mm longer, which can contribute to stability at speed.

Frame stack
+8 mm
Higher front end
Frame reach
+5 mm
Longer frame reach
Wheelbase
+19 mm
Longer: steadier at speed
Head angle
±0.0°
About the same head angle
Chainstays
+10 mm
Longer: more planted

The two frames

2026 Polygon Siskiu T T6 UDH (M)The Polygon Siskiu T T6 UDH frame drawn to scale.J 1214

Only the Polygon Siskiu T T6 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 T6 UDH MTrek Fuel EX MLDifference
Reach465470+5 mm
Stack609616.8+8 mm
Head tube angle64.564.5±0.0°
Seat tube angle71.2not listed
Effective top tube595607.4+12 mm
Chainstay length430440+10 mm
Wheelbase12141233.1+19 mm
BB height337.5335−3 mm
Standover705741.8+37 mm
Seat tube length400420+20 mm
Head tube length95100+5 mm
BB dropnot listed38

Differences are the Trek Fuel EX minus the Polygon Siskiu T T6 UDH. Full charts: 2026 Polygon Siskiu T T6 UDH, 2025 Trek Fuel EX.

Where each sits in its class

Polygon Siskiu T T6 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 T6 UDHT6 with UDHTrek Fuel EX5
FramePolygon ALX TrailTrek Fuel EX
ForkRockShox Recon Silver TKRockShox Recon Silver
Rear shockX-Fusion O2 ProX-Fusion Pro 2
ShifterShimano CUESShimano Deore M6100
DerailleurShimano CUESShimano Deore M6100
CassetteShimano CUESShimano Deore M6100
ChainKMC XGlideShimano Deore M6100
CranksetSamox RAC61CShimano MT512
PedalsPolygon Expertnot listed
WheelsetPolygon MT6Bontrager Line TLR 30
TireMaxxis DissectorBontrager Gunnison Elite XR
BrakeShimano MT200Shimano MT200
RotorShimano SM-RT10Shimano SM-RT56
HandlebarPolygon EXPERTTranzX JD-YSI-22PLQ
StemPolygon EXPERTBontrager Comp
HeadsetFSA No 57Enot listed
Dropper postX-Fusion MANIC LCTranzX JD-YSI-22PLQ
SaddleLinc XTENTBontrager Arvada
Bottom bracketnot listedShimano MT501
Gripsnot listedBontrager XR Trail

Know what is on every bike.

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