Polygon Siskiu T6

Name: Polygon Siskiu T6
Brand: Polygon

2026 MountainTrail Manufacturer page

Last known price: $1,799

Prices shown first for United States
Travel: 140 / 135 mm Fork / rear shock
Wheels: 29″
Drivetrain: 1 × 10 34t / 11–48t
Gear range: 436%
Frame: Aluminum
Brakes: Hydraulic disc

Rider height by size (cm)

Size guide

SM 157.5–169
MD 166–179
LG 176–187
XL 184–195.6

Components

16 of 22 identified

Parts found in a manufacturer catalog show their brand, model and key numbers, and the steps show how precisely they are identified: brand, series, model, or the exact product. The info button has every detail and the text the manufacturer published.

Frame and fork

1 part

Frame

ALX Trail 6061 Aluminum, 29" Wheels, UDH Compatible, All-New Brazed-In Cable Ports, Accessory Mount, One Piece Unibody Pivot Bridge, 135mm Travel, Direct Post-Mount Disc Brake, 148x12mm Boost Thru-Axle, Threaded BB, ISCG 05 Tabs, 34.9mm Seatpost Clamp Not identified

Suspension

2 parts

Drivetrain

6 parts

Bottom bracket

BSA, 73mm, threaded Not identified
Cassette
- Shimano CS-LG300-10 10 speeds
CS-LG300-10
Chain
- KMC XGlide 11 speeds
Crankset

32T, Max Chainring: 34T Not identified
Rear derailleur
- Shimano Cues RD-U6000 11 speeds
RD-U6000RD-U6000-GS
Shifters
- Shimano Cues SL-U6000
SL-U6000

Brakes

2 parts

Brakes
- Shimano BL-MT200
BL-MT200
Disc rotors
- Shimano SM-RT10
SM-RT10

Wheels and tires

4 parts

Cockpit and contact points

7 parts

Grips

LINC Rubber, Black, 134 mm Length, Ø25 mm Not identified
Handlebar
- Polygon
Headset
- FSA NO.57E
Pedals

Alloy Flat Pedals With Replaceable Pins Not identified
Saddle

LINC Xtend, Cr-Mo Rails (Ø 7mm) Not identified
Seatpost
- X-Fusion
Stem
- Polygon

Sizes and geometry

4 sizes Open in the geometry plotter

Enter your height to highlight matching ranges.

Size MD

Table

Reach 465mm

Stack 609mm

Wheelbase 1214mm

Head angle 64.5°

Seat angle 77.0°

Every size is drawn to the same scale, in millimeters. Explanatory schematic on an assumed 29″ wheel; exact published values are in the table below.

Size Reported by the manufacturer

Complete manufacturer geometry table 4 published sizes

Complete manufacturer geometry by size
Measurement
Frame
Reachmm	440	465	485	505
Stackmm	604	609	622	636
Top tube lengthmm	568	595	619	644
Seat tube lengthmm	390	400	415	430
Head tube lengthmm	89	95	110	125
Head tube angle	64.5°	64.5°	64.5°	64.5°
Seat tube angle	77°	77°	76°	77°
Chainstay lengthmm	430	430	432	430
Wheelbasemm	1186	1214	1240	1267
Front centermm	759	787	811	840
Bottom bracket dropmm	39	39	39	39
Bottom bracket heightmm	337.5	337.5	337.5	337.5
Standover heightmm	704	705	711	723
Fork rakemm	44	44	42	44
Trailmm	130	130	132	130
Stack/reach ratio	1.37	1.31	1.28	1.26
Suspension and parts
Front travelmm	140	140	140	140
Rear travelmm	135	135	135	135
Crank lengthmm	165	165	165	165
Handlebar widthmm	780	780	780	780
Stem lengthmm	35	35	35	35
Dropper post travelmm	150	150	170	170

Not published by the manufacturer: Stem angle and Seatpost length.

Specifications

Frame and fork

Intended fit: Unisex
Frame material: Aluminum

Suspension

Suspension configuration: Full suspension
Front travel: 140 mm
Rear travel: 135 mm

Drivetrain

Derived by Bikelake

Front chainrings: 1
Smallest chainring: 34
Largest chainring: 34
Rear sprockets: 10
Smallest sprocket: 11
Largest sprocket: 48
Lowest gear: 20.5 in
Highest gear: 89.6 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

Derailleur hanger: UDH
Seatpost: Dropper seatpost
Shifting: Mechanical

Additional specifications

Bottom bracket standard: BSA
Fork spring: Air
Tire clearance: Maximum tire width: 2.6″
Tire width: 2.4″
Wheel material: Aluminum
Wheel size: 29″

Technical analysis

4 measures

How these figures sit among bicycles of the same class and model year. Context, not a ranking.

Front travel

140 mm

This value is within the central range for this class.

Cohort: Mountain / Trail Model year: 2026
Sample: 1,644 bicycles with this information
Coverage: 96.3% of the class

Lowest gear

20.5 gear inches

This value is above the central range for this class.

Cohort: Mountain / Trail Model year: 2026
Sample: 1,229 bicycles with this information
Coverage: 72.0% of the class

Highest gear

89.6 gear inches

This value is within the central range for this class.

Cohort: Mountain / Trail Model year: 2026
Sample: 1,229 bicycles with this information
Coverage: 72.0% of the class

Shifting

Mechanical

389 of 1,706 bicycles with this information use electronic shifting.

Cohort: Mountain / Trail Model year: 2026
Sample: 1,706 bicycles with this information
Coverage: 100.0% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 7.9 km/h
Highest gear: 34.3 km/h

Total gear range 436%

Technical details and class reference

These speeds describe the gearing at the selected cadence, not how fast you can ride.
Calculated from published gear-inch values and their wheel-size assumptions.
These gearing values describe the bicycle, not a selected frame size.
A 100% range means one ratio; 500% means the highest ratio is five times the lowest.
For e-bikes, motor assistance cutoff is not represented.

Gear-inch range

Lower gear-inch values travel less distance per pedal revolution; higher values travel farther.

This bicycle: 20.5–89.6 gear inches
Class reference (p10–p90): 17.1–98.6 gear inches; The band runs from p10 for the lowest gear to p90 for the highest gear.

Cohort: Mountain / Trail Model year: 2026
Lowest gear: 1229 bicycles with this information, 72.0% of the class
Highest gear: 1229 bicycles with this information, 72.0% of the class

Lineup changes

The published facts that differ across this family's builds and from the same model a year earlier. Missing information never counts as zero.

Differences across 2026 builds
Specification	This bicycle Polygon Siskiu T6	Polygon Siskiu D24	Polygon Siskiu D5	Polygon Siskiu D6	Polygon Siskiu D6 LTD	Polygon Siskiu D7
Suspension
Front travel	140 mm	120 mm	120 mm	120 mm	120 mm	120 mm
Rear travel	135 mm	120 mm	120 mm	120 mm	120 mm	Not informed
Drivetrain
Smallest chainring	34	30	32	32	24	32
Largest chainring	34	30	32	32	24	32
Rear sprockets	10	8	9	10	10	11
Smallest sprocket	11	12	11	11	11	11
Largest sprocket	48	42	46	48	48	50
Lowest gear	20.5 in	17.1 in	19.1 in	19.3 in	13.8 in	18.6 in
Highest gear	89.6 in	60.0 in	80.0 in	84.4 in	60.0 in	84.4 in
Cockpit
Derailleur hanger	UDH	Not informed	Not informed	Not informed	Not informed	Not informed
Seatpost	Dropper seatpost	Rigid seatpost	Rigid seatpost	Dropper seatpost	Dropper seatpost	Dropper seatpost
Other specifications
Bottom bracket standard	BSA	Not informed	BSA	BSA	BSA	BSA
Fork spring	Air	Air	Coil	Coil	Air	Air
Tire clearance	Maximum tire width: 2.6″	Maximum tire width: 2.5″	Maximum tire width: 2.25″	Not informed	Maximum tire width: 2.4″	Not informed
Tire width	2.4″	2.4″	2.25″	2.25″	2.25″	2.25″
Wheel size	29″	24″	27.5″	27.5″ / 29″	27.5″	27.5″ / 29″