Polygon Siskiu T8

2018 MountainTrail

Last known price: $2,499

Prices shown first for United States
Travel: 150 / 140 mm Fork / rear shock
Wheels: 27.5″
Drivetrain: 1 × 11 32t / 11–46t
Gear range: 418%
Frame: Aluminum
Brakes: Hydraulic disc

Rider height by size (cm)

Size guide

SM 158–171
MD 168–180
MD 168–180
LG 178–189
XL 186–199

Components

16 of 21 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

Aluminum Not identified

Suspension

2 parts

Drivetrain

8 parts

Bottom bracket

BSA threaded Not identified
Cassette

11-speed, 11-46 tooth Not identified
Chain
- KMC X11 11 speeds
X-11
Chain guide

None
Crankset
- Prowheel
Front derailleur

None
Rear derailleur
- Shimano RD-M800
RD-M800
Shifters
- Shimano SLX SL-M7000
SL-M7000SL-M7000-IR

Brakes

2 parts

Brake levers
- Shimano
BR-MT500
Brakes
- Shimano BR-MT500
BR-MT500

Wheels and tires

4 parts

Cockpit and contact points

6 parts

Handlebar
- Entity
Headset

ZS 44/28.6 Not identified
Pedals

Alloy Not identified
Saddle
- Entity
Seatpost
- Tranz-X
Stem
- Entity

Sizes and geometry

5 sizes Open in the geometry plotter

Enter your height to highlight matching ranges.

Size MD

Table

Reach 430mm

Stack 618mm

Wheelbase 1171mm

Head angle 66.5°

Seat angle 74.5°

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 Reported by the manufacturer

Complete manufacturer geometry table 5 published sizes

Complete manufacturer geometry by size
Measurement
Reachmm	410	430	430	450	475
Stackmm	595.1	599.7	618.4	623	627.6
Top tube lengthmm	571	596.3	601.5	627.4	656.7
Seat tube lengthmm	395	435	435	485	520
Head tube lengthmm	105	110	100	105	110
Head tube angle	66°	66°	66.5°	66.5°	66.5°
Seat tube angle	74.9°	74.5°	74.5°	74.1°	73.9°
Chainstay lengthmm	430	430	435	435	435
Wheelbasemm	1145.9	1168	1170.8	1192.8	1219.8
Front centermm	717	739	736	758	785
Bottom bracket dropmm	19	19	18	18	18
Bottom bracket heightmm	336.5	336.5	337	337	337
Standover heightmm	663.3	695.1	697.9	734.3	758.7
Fork rakemm	46	46	41	41	41
Trailmm	108	108	110	110	110
Stack/reach ratio	1.45	1.40	1.44	1.38	1.32

Not published by the manufacturer: Front travel, Rear travel, Crank length, Handlebar width, Stem length, Stem angle, Seatpost length and Dropper post travel.

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: 32
Largest chainring: 32
Rear sprockets: 11
Smallest sprocket: 11
Largest sprocket: 46
Lowest gear: 19.1 in
Highest gear: 80.0 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 width: 2.6″
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: 2018
Sample: 925 bicycles with this information
Coverage: 98.6% of the class

Lowest gear

19.1 gear inches

This value is within the central range for this class.

Cohort: Mountain / Trail Model year: 2018
Sample: 845 bicycles with this information
Coverage: 90.0% of the class

Highest gear

80.0 gear inches

This value is within the central range for this class.

Cohort: Mountain / Trail Model year: 2018
Sample: 845 bicycles with this information
Coverage: 90.0% of the class

Shifting

Mechanical

25 of 938 bicycles with this information use electronic shifting.

Cohort: Mountain / Trail Model year: 2018
Sample: 938 bicycles with this information
Coverage: 100.0% of the class

Gearing

Estimated speeds at 80 rpm

Lowest gear: 7.3 km/h
Highest gear: 30.6 km/h

Total gear range 418%

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: 19.1–80.0 gear inches
Class reference (p10–p90): 16.5–93.5 gear inches; The band runs from p10 for the lowest gear to p90 for the highest gear.

Cohort: Mountain / Trail Model year: 2018
Lowest gear: 845 bicycles with this information, 90.0% of the class
Highest gear: 845 bicycles with this information, 90.0% 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 2018 builds

Differences across 2018 builds
Specification	This bicycle Polygon Siskiu T8	Polygon Siskiu D5	Polygon Siskiu D6	Polygon Siskiu D7	Polygon Siskiu D8	Polygon Siskiu T7
Suspension
Front travel	150 mm	120 mm	120 mm	120 mm	120 mm	150 mm
Rear travel	140 mm	120 mm	120 mm	120 mm	120 mm	140 mm
Drivetrain
Front chainrings	1	3	3	2	2	1
Smallest chainring	32	22	22	22	24	32
Largest chainring	32	40	40	36	34	32
Rear sprockets	11	9	10	10	11	10
Largest sprocket	46	34	36	36	42	42
Lowest gear	19.1 in	17.8 in	16.8 in	16.8 in	15.7 in	21.0 in
Highest gear	80.0 in	100.0 in	100.0 in	90.0 in	85.0 in	80.0 in
Cockpit
Seatpost	Dropper seatpost	Rigid seatpost	Rigid seatpost	Rigid seatpost	Rigid seatpost	Dropper seatpost
Other specifications
Bottom bracket standard	BSA	BSA	BSA	Not informed	BSA	BSA
Tire width	2.6″	2.25″	2.25″	2.25″	2.25″	2.6″