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2021 Polygon Syncline C5

Original specifications: geometry for 5 published sizes.

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At a glance

Archive #900001792
Model year
2021
Category
Mountain
Original MSRP
$1,499.00
Sizes
27.5” SM, 27.5” MD, 29” MD, 29” LG, 29” XL
Colors
Red Black
Geometry
5 manufacturer sizes
In this record
20 specifications · archived image · original MSRP · geometry
Campaign
Original buildCarbon Fiber

Manufacturer catalog

Published sizes and colors

5 sizes · 1 color

Manufacturer-published sizes and colors; availability and exact size/color pairings may vary by market or production run.

Published sizes

27.5” SM27.5” MD29” MD29” LG29” XL

Published colors

Red Black

Frameset

Frame ConstructionACX XC Performance
Frame MaterialCarbon Fiber
ForkFOX 32 Rhythm, 120mm

Drivetrain

ShiftersShimano SLX SL-M7100-R 12-speed Trigger
Rear DerailleurShimano SLX RD-M7100-SGS Direct Attach
CranksetShimano SLX FC-M7100-1 32T 2-Piece-Crank
Bottom BracketShimano BB-MT500-PA
Cassette12 Speed 11-51T
ChainKMC New X-12
PedalsAlloy Cage Pedal W/ Reflector

Brakes

BrakesShimano MT400 Hydraulic Disc Brake; Levers: Shimano MT400 Hydraulic Disc Brake; Rotors: Front:180mm Rear:160mm Center-Lock

Cockpit & Contact Points

HeadsetIntegrated W/ Sealed Bearing for Taper Head Tube, IS 42/28.6 | IS 52/40
HandlebarENTITY XPERT, W: 740mm, BB: 31.8mm, R/D: 12mm, B: 9degree
StemENTITY XPERT, EXT: 60mm, BB: 31.8mm, R/D: 7degree
SaddleEntity Void Saddle
SeatpostEntity Xpert, 27.2X350mm

Wheels & Tires

WheelsAlloy Double Wall
Rims584-30 / 622-30 32H for Tyre 584 / 622-54/76 Tubeless Ready
Front TireWTB Trail Boss Tire, 27.5X2.25 / 29x2.25
Rear TireWTB Trail Boss Tire, 27.5X2.25 / 29x2.25

Geometry

5 sizes · 13 measurements

Frame measurements by size.

All geometry measurements5 sizes · 13 measurements
MeasurementS (27.5”)M (27.5”)M (29”)L (29”)XL (29”)
Seat tube380 mm420 mm420 mm460 mm500 mm
Effective top tube569 mm594.6 mm597.7 mm621 mm649.15 mm
Head tube100 mm120 mm100 mm120 mm140 mm
Head-tube angle67°67°67°67°67°
Seat-tube angle75.5°75.3°75.3°75.3°75.5°
Actual seat-tube angle73°73°73°73°73°
Chainstay / rear center428 mm425 mm435 mm435 mm435 mm
Wheelbase1106.94 mm1134.8 mm1149.5 mm1176.9 mm1204.76 mm
Bottom-bracket drop45 mm45 mm65 mm65 mm65 mm
Bottom-bracket height308 mm308.5 mm307.5 mm307.5 mm304.5 mm
Reach410 mm430 mm430 mm450 mm470 mm
Stack596.6 mm615 mm633.2 mm651.6 mm670 mm
Standover height690.9 mm729.2 mm730.8 mm763.7 mm779.2 mm

Dimensions as recorded.

Gearing

Lower gears help on climbs. Higher gears suit higher speeds.

RPM

RPM = pedal turns per minute.

S (27.5”), M (27.5”)32T · 11–51T · 12-speed
Lowest0.63:1 Highest2.91:1 Total range464%
Estimated speed At 90 RPM Lowest gear4.6 mph Highest gear21.4 mph

Rear tire: 27.5×2.25.

M (29”), L (29”), XL (29”)32T · 11–51T · 12-speed
Lowest0.63:1 Highest2.91:1 Total range464%
Estimated speed At 90 RPM Lowest gear4.9 mph Highest gear22.6 mph

Rear tire: 29×2.25.

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 other gearing

Try your current gearingChanged tires or gears? Calculate your setup.

Your changes apply to this calculation. The archived build stays unchanged.

Your gearing setup
Gears

Use up to three front tooth counts, separated by /. For one rear sprocket, enter the same count twice.

Rear tire

Apply the marking on your rear tire or edit its dimensions below. Older or fractional inch sizes need the ISO marking (e.g. 37-590).

For 32-622, width is 32 mm and rim diameter is 622 mm. Use the rear tire on mixed-wheel bikes. Leave both fields empty to compare ratios only.

Gear, dimension and cadence changes update results automatically.

Speeds are estimates. These calculations do not establish component compatibility or available tire clearance.

Parts & serviceability

Find replacement parts

Original specifications
Rear derailleur · Original
SHIMANO SLX RD-M7100-SGS DIRECT ATTACH
Retailer offers
Seatpost · Original
ENTITY XPERT

27.2x350mm

Retailer offers
Chain · Original
KMC NEW X-12
More parts (4)Fewer parts
Front tire · Original
WTB TRAIL BOSS TIRE

27.5x2.25 / 29x2.25

Bottom bracket · Original
SHIMANO BB-MT500-PA
Crankset · Original
SHIMANO SLX FC-M7100-1 32T 2-PIECE-CRANK
Shifters · Original
SHIMANO SLX SL-M7100-R 12-SPEED TRIGGER

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
WTB TRAIL BOSS TIRE, 27.5x2.25 / 29x2.25
Rear tire
WTB TRAIL BOSS TIRE, 27.5x2.25 / 29x2.25
Drivetrain
12-speed
Seatpost diameter
27.2 mm
Bottom bracket / shell
SHIMANO BB-MT500-PA
Equipment inspection checks 14 checks based on 6 archived component groups Open equipment checksClose equipment checks
0 of 14 checked Progress stays in this browser for this record.

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 →

Archived: Frame: ACX XC PERFORMANCE · Fork: FOX 32 RHYTHM, 120mm

Archived: Fork: FOX 32 RHYTHM, 120mm · Rear shock: -

Archived: Shifters: SHIMANO SLX SL-M7100-R 12-SPEED TRIGGER · Rear derailleur: SHIMANO SLX RD-M7100-SGS DIRECT ATTACH · Crankset: SHIMANO SLX FC-M7100-1 32T 2-PIECE-CRANK · Bottom bracket: SHIMANO BB-MT500-PA · Cassette: 12 SPEED 11-51T · Chain: KMC NEW X-12

Archived: Brakes: SHIMANO MT400 HYDRAULIC DISC BRAKE; Levers: SHIMANO MT400 HYDRAULIC DISC BRAKE; Rotors: FRONT:180mm REAR:160mm CENTER-LOCK

Archived: Wheels: ALLOY DOUBLE WALL · Rims: 584-30 / 622-30 32H FOR TYRE 584 / 622-54/76 TUBELESS READY · Front tire: WTB TRAIL BOSS TIRE, 27.5x2.25 / 29x2.25 · Rear tire: WTB TRAIL BOSS TIRE, 27.5x2.25 / 29x2.25

Controls and contact points

Archived: Headset: INTEGRATED W/ SEALED BEARING FOR TAPER HEAD TUBE, IS 42/28.6 | IS 52/40 · Handlebar: ENTITY XPERT, W: 740mm, BB: 31.8mm, R/D: 12mm, B: 9degree · Stem: ENTITY XPERT, EXT: 60mm, BB: 31.8mm, R/D: 7degree · Seatpost: ENTITY XPERT, 27.2x350mm · Saddle: ENTITY VOID SADDLE · Pedals: ALLOY CAGE PEDAL W/ REFLECTOR

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Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.

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