Polygon Siskiu T27

Name: Polygon Siskiu T27
Brand: Polygon

2026 MountainTrail Manufacturer page

Last known price: $1,499

Prices shown first for United States
Travel: 150 / 140 mm Fork / rear shock
Wheels: 27.5″
Drivetrain: 1 × 10 34t / 11–48t
Gear range: 436%
Frame: Aluminum
Brakes: Hydraulic disc

Sizes

Size guide

The manufacturer did not publish rider heights for these sizes.

Components

15 of 20 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 Frame, One-Piece Linkage Suspension Platform, 140 mm Travel (27.5”), Internal Cable Routing for Dropper Post and Derailleur, Direct Post-Mount Disc Brake, 148×12 mm Boost Thru-Axle, 73 mm Threaded BB, ISCG 05 Tabs Not identified

Suspension

2 parts

Drivetrain

6 parts

Bottom bracket

BSA, 73mm, threaded Not identified
Cassette
- Shimano CS-LG300-10 10 speeds 11–48t
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 BR-MT200
BR-MT200
Disc rotors

180mm Front and Rear Not identified

Wheels and tires

4 parts

Cockpit and contact points

5 parts

Handlebar
- Polygon
Pedals

Alloy Flat Pedals with Replaceable Pins and Reflectors Not identified
Saddle
- Fizik Terra Alpaca X5
Seatpost
- X-Fusion
Stem
- Polygon

Sizes and geometry

1 size Open in the geometry plotter

Complete rider-height ranges are not published for these sizes. You can still explore the geometry below.

Size XS

Table

Reach 420mm

Stack 579mm

Wheelbase 1146mm

Head angle 65.0°

Seat angle 76.5°

Every size is drawn to the same scale, in millimeters. Explanatory schematic on an assumed 27.5″ wheel; exact published values are in the table below.

Size Reach Stack

Complete manufacturer geometry table 1 published size

Complete manufacturer geometry by size
Measurement
Frame
Reachmm	420
Stackmm	578.9
Top tube lengthmm	559.2
Seat tube lengthmm	375
Head tube lengthmm	90
Head tube angle	65°
Seat tube angle	76.5°
Chainstay lengthmm	425
Wheelbasemm	1146.4
Front centermm	722
Bottom bracket dropmm	20
Bottom bracket heightmm	335
Standover heightmm	666
Fork rakemm	37
Trailmm	125
Stack/reach ratio	1.38
Suspension and parts
Front travelmm	150
Rear travelmm	140
Dropper post travelmm	150

Not published by the manufacturer: Crank length, Handlebar width, Stem length, Stem angle and Seatpost length.

Specifications

Frame and fork

Intended fit: Unisex
Frame material: Aluminum

Suspension

Suspension configuration: Full suspension
Front travel: 150 mm
Rear travel: 140 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: 19.5 in
Highest gear: 85.0 in

Wheels and brakes

Wheel configuration: Same size
Brake type: Hydraulic disc

Fit and controls

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: 27.5″

Technical analysis

4 measures

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

Front travel

150 mm

This value is above 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

19.5 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

85.0 gear inches

This value is below 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: 7.5 km/h
Highest gear: 32.6 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: 19.5–85.0 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 T27	Polygon Siskiu D24	Polygon Siskiu D5	Polygon Siskiu D6	Polygon Siskiu D6 LTD	Polygon Siskiu D7
Suspension
Front travel	150 mm	120 mm	120 mm	120 mm	120 mm	120 mm
Rear travel	140 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	19.5 in	17.1 in	19.1 in	19.3 in	13.8 in	18.6 in
Highest gear	85.0 in	60.0 in	80.0 in	84.4 in	60.0 in	84.4 in
Cockpit
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	27.5″	24″	27.5″	27.5″ / 29″	27.5″	27.5″ / 29″