Rear tire: 27.5×2.4.
Velopedia Bicycle Archive
2025 Polygon Siskiu T27 EVO
Original specifications: geometry for 1 published size.
Planning to sell? Draft your listing
At a glance
Archive #900001778- Model year
- 2025
- Category
- Mountain
- Original MSRP
- $1,999.00
- Sizes
- XS
- Colors
- Cream
- Geometry
- 1 manufacturer size
- In this record
- 22 specifications · 6 archived images · original MSRP · geometry
Original buildAluminum
Frameset
| Frame Construction | ALX Trail 140mm Travel |
|---|---|
| Frame Material | Aluminum |
| Fork | RockShox Recon Silver-RL 150mm Travel |
| Rear Shock | RockShox Deluxe Select Plus, E2E: 210x55mm |
Drivetrain
| Shifters | Shimano Deore SL-M6100, 1X12-Speed Trigger |
|---|---|
| Rear Derailleur | Shimano Deore RD-M6100-SGS Direct Attach |
| Crankset | Shimano FC-M6120-1 Boost, 32T |
| Bottom Bracket | Shimano 2-Piece Crankset BSA Threaded |
| Cassette | Shimano Deore CS-M6100-12, 10-51T Microspline |
| Chain | KMC New X-12 |
| Pedals | Alloy Flat Pedal W/ Replaceable PIN & Reflector |
Brakes
| Brakes | Shimano Hydraulic Disc Brakes; Levers: Shimano BL-M4100; Rotors: Shimano SM-RT54, 180mm Center-Lock |
|---|
Cockpit & Contact Points
| Headset | FSA no.57E for Taper H/T, ZS 44/28.6 | ZS 56/40 |
|---|---|
| Handlebar | POLYGON EXPERT, W: 720mm, BB: 35mm, R/D: 30mm, B: 9 degree |
| Stem | POLYGON EXPERT, E: 35mm, BB: 35mm, R/D: 0 degree |
| Saddle | Fizik Terra Alpaca X5 |
| Seatpost | Dropper Post Xfusion Manic LC 100mm Travel, DXL: 30.9 X 314mm |
Wheels & Tires
| Hubs | F: Shimano HB-TC500-15-B Thru Axle 15x110mm 32H Center-Lock, R: Shimano FH-TC500-MS-B Thru Axle 12x148mm 32H Center-Lock for Microspline |
|---|---|
| Wheels | Polygon MT6 |
| Rims | Alloy Double Wall H: 18mm W: 29mm 584-27.5 32H for Tyre 584-54/76 TL Ready |
| Front Tire | Maxxis Dissector 27.5"X2.40" |
| Rear Tire | Maxxis Dissector 27.5"X2.40" |
No specifications match. Try a component name or clear your search.
Geometry
Frame measurements by size.
Frame diagram
Select an available measurement to locate it on the frame.
All geometry measurements1 size · 13 measurements
| Measurement | XS |
|---|---|
| Seat tube | 375 mm |
| Effective top tube | 559.2 mm |
| Head tube | 90 mm |
| Head-tube angle | 65° |
| Seat-tube angle | 76.5° |
| Actual seat-tube angle | 71° |
| Chainstay / rear center | 425 mm |
| Wheelbase | 1146.4 mm |
| Bottom-bracket drop | 20 mm |
| Bottom-bracket height | 335 mm |
| Reach | 420 mm |
| Stack | 579.87 mm |
| Standover height | 666 mm |
Dimensions as recorded.
Gearing
Lower gears help on climbs. Higher gears suit higher speeds.
RPM = pedal turns per minute.
How it works
Ratio = front teeth ÷ rear teeth. Hub gears also include the hub’s internal ratio. A 400% range means the highest ratio is four times the lowest.
Speeds are estimates from tire size and pedal cadence. Actual speeds vary.
Try your current gearingChanged tires or gears? Calculate your setup.
Your changes apply to this calculation. The archived build stays unchanged.
Gearing results
| Measure | Original | Your setup |
|---|---|---|
| Lowest ratio | — | — |
| Highest ratio | — | — |
| Total range | — | — |
| Lowest-gear speed | — | — |
| Highest-gear speed | — | — |
Speeds are estimates. These calculations do not establish component compatibility or available tire clearance.
Parts & serviceability
Find replacement parts

Shimano Deore CN-M6100 Chain Silver, 12 Speed, 126 Links
Replacement option
10-51T MICROSPLINE

Shimano Deore CS-M6200 12-Speed Cassette Black, 10-51t, HG
Replacement option

Maxxis Dissector 27.5in Tire Black, 3CT/EXO, 27.5x2.4
Model match
Other replacement options (1)

Specialized Trail Control Grid Lite T7 TLR Tire Black, 27.5x2.4
Replacement option
More parts (7)Fewer parts
ZS 44/28.6 | ZS 56/40

Cane Creek 40-Series Headset Black, ZS44/28.6, ZS56/40
Replacement option
32T
1x12-SPEED TRIGGER
DxL: 30.9 x 314mm
Based on the original build. Check fit and installed parts before ordering. Affiliate links may earn Velopedia a commission. As an Amazon Associate I earn from qualifying purchases.
Parts and service referenceQuick reference before buying parts
Archived specifications for reference. Check the fitted parts before ordering.
- Front tire
- MAXXIS DISSECTOR 27.5"x2.40"
- Rear tire
- MAXXIS DISSECTOR 27.5"x2.40"
- Seatpost diameter
- 30.9 mm
- Bottom bracket / shell
- SHIMANO 2-PIECE CRANKSET BSA THREADED
Equipment inspection checks 13 checks based on 6 archived component groups Open equipment checksClose equipment checks
Checks selected from the archived equipment. Confirm what is fitted today. This is not a complete safety inspection; use the full inspection guide before test riding.
Full used-bike inspection guide →
Frame and fork
Inspect the frame and fork →Archived: Frame: ALX TRAIL 140mm TRAVEL · Fork: ROCKSHOX RECON SILVER-RL 150mm TRAVEL
Suspension
Evaluate the suspension →Archived: Fork: ROCKSHOX RECON SILVER-RL 150mm TRAVEL · Rear shock: ROCKSHOX DELUXE SELECT PLUS, E2E: 210x55mm
Drivetrain
Check drivetrain wear →Archived: Shifters: SHIMANO DEORE SL-M6100, 1x12-SPEED TRIGGER · Rear derailleur: SHIMANO DEORE RD-M6100-SGS DIRECT ATTACH · Crankset: SHIMANO FC-M6120-1 BOOST, 32T · Bottom bracket: SHIMANO 2-PIECE CRANKSET BSA THREADED · Cassette: SHIMANO DEORE CS-M6100-12, 10-51T MICROSPLINE · Chain: KMC NEW X-12
Brakes
Inspect the brakes →Archived: Brakes: SHIMANO HYDRAULIC DISC BRAKES; Levers: SHIMANO BL-M4100; Rotors: SHIMANO SM-RT54, 180mm CENTER-LOCK
Wheels and tires
Check wheels and tires →Archived: Wheels: POLYGON MT6 · Rims: ALLOY DOUBLE WALL H: 18mm W: 29mm 584-27.5 32H FOR TYRE 584-54/76 TL READY · Hubs: F: SHIMANO HB-TC500-15-B THRU AXLE 15x110mm 32H CENTER-LOCK, R: SHIMANO FH-TC500-MS-B THRU AXLE 12x148mm 32H CENTER-LOCK FOR MICROSPLINE · Front tire: MAXXIS DISSECTOR 27.5"x2.40" · Rear tire: MAXXIS DISSECTOR 27.5"x2.40"
Controls and contact points
Archived: Headset: FSA NO.57E FOR TAPER H/T, ZS 44/28.6 | ZS 56/40 · Handlebar: POLYGON EXPERT, W: 720mm, BB: 35mm, R/D: 30mm, B: 9 degree · Stem: POLYGON EXPERT, E: 35mm, BB: 35mm, R/D: 0 degree · Seatpost: DROPPER POST XFUSION MANIC LC 100mm TRAVEL, DxL: 30.9 x 314mm · Saddle: FIZIK TERRA ALPACA X5 · Pedals: ALLOY FLAT PEDAL W/ REPLACEABLE PIN & REFLECTOR
Have you owned this model?Help preserve its real-world history by sharing your owner experience.
Share the details that would help another rider understand how this model fits, rides and holds up over time. Velopedia reviews every contribution before publication.
Already contributed? Send me a fresh private edit link
For privacy, Velopedia shows the same confirmation whether or not an experience exists.
Gallery6 images
Checking current listings…
Find this bike on eBay
Search eBay US; check the model year, size and installed components. We may earn a commission from purchases.
Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.





