Velopedia Bicycle Archive
2023 Polygon Tambora G8X
Cyclocross/Gravel bicycle from the Velopedia specification archive.
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What Velopedia knows
- Model year
- 2023
- Category
- Gravel & Cyclocross
- Original MSRP
- $2,999.00
- Sizes
- S, M, L, XL
- Colors
- Brown
- Geometry
- 8 manufacturer sizes · Geometry context
- Record coverage
- 21 preserved details · archived image · original MSRP · preserved geometry
- Archive ID
- 900001855
Frameset
| Frame Construction | ACX Gravel |
|---|---|
| Frame Material | Carbon Fiber |
| Fork | Carbon Rigid |
| Fork Material | Carbon Fiber |
Drivetrain
| Shifters | SRAM Rival eTap AXS 12-speed Brifter |
|---|---|
| Rear Derailleur | SRAM Rival Xplr eTap AXS 12-speed |
| Crankset | SRAM Rival 1 Wide 40T |
| Bottom Bracket | SRAM DUB T47 |
| Cassette | SRAM XG-1251 12 Speed 10-44T XDR |
| Chain | SRAM Rival 12-speed |
Brakes
| Brakes | SRAM Rival Hydraulic Disc; Levers: SRAM Rival; Rotors: SRAM Paceline 160mm CL |
|---|
Cockpit & Contact Points
| Headset | Token TK155SP-36 W/ Sealed Bearing |
|---|---|
| Handlebar | ALLOY FLARE 16degree, W: 420mm (S, M) / 440mm (L, XL), BB: 31,8mm, R/D: 125mm, B/R: 77mm |
| Stem | ALLOY STEM, EXT: 90mm (S, M) / 100mm (L, XL), BB: 31,8mm, R/D: 7degree |
| Saddle | Selle Italia Model X |
| Seatpost | Carbon, DXL: 27,.2 X 300mm (S,M,L) / 27.2 X 350mm (XL) |
Wheels & Tires
| Hubs | F: Novatec D791 12x100mm 24H CL / R: Novatec D792 12x142mm 24H CL for XDR |
|---|---|
| Wheels | Novatec G24 Disc (28mm) W/ Tubeless Tape Installed |
| Rims | Carbon FV H: 28 622x24 24H for Tyre 622-35/68 TLR |
| Front Tire | 700x40C 622x40 TLR |
| Rear Tire | 700x40C 622x40 TLR |
Size-specific frame data
Geometry
Manufacturer-published geometry normalized for consistent archival comparison. Effective top tube and reach remain separate measurements because they describe different aspects of fit.
| Measurement | S · Speed Gravel | M · Speed Gravel | L · Speed Gravel | XL · Speed Gravel | S · All Road | M · All Road | L · All Road | XL · All Road |
|---|---|---|---|---|---|---|---|---|
| Seat tube | 404 mm | 448 mm | 492 mm | 535 mm | 404 mm | 448 mm | 492 mm | 535 mm |
| Effective top tube | 526 mm | 551 mm | 581 mm | 611 mm | 526 mm | 550 mm | 581 mm | 610 mm |
| Head tube | 143 mm | 163 mm | 193 mm | 221 mm | 143 mm | 163 mm | 193 mm | 221 mm |
| Head-tube angle | 70° | 71.5° | 71.8° | 72° | 70.25° | 71.77° | 72.06° | 72.26° |
| Seat-tube angle | 74.5° | 74° | 73.5° | 73° | 74.75° | 74.26° | 73.76° | 73.26° |
| Actual seat-tube angle | 74.5° | 74° | 73.5° | 73° | 74.75° | 74.26° | 73.76° | 73.26° |
| Chainstay / rear center | 425 mm | 425 mm | 425 mm | 425 mm | 415 mm | 415 mm | 415 mm | 415 mm |
| Wheelbase | 1017 mm | 1022 mm | 1045 mm | 1067 mm | 997 mm | 1003 mm | 1026 mm | 1048 mm |
| Bottom-bracket drop | 78 mm | 78 mm | 78 mm | 78 mm | 79 mm | 79 mm | 79 mm | 79 mm |
| Bottom-bracket height | 280 mm | 280 mm | 280 mm | 280 mm | 265 mm | 265 mm | 265 mm | 265 mm |
| Reach | 369 mm | 381 mm | 397 mm | 412 mm | 371 mm | 383 mm | 400 mm | 415 mm |
| Stack | 568 mm | 593 mm | 622 mm | 650 mm | 566 mm | 591 mm | 621 mm | 648 mm |
| Standover height | 716 mm | 755 mm | 798 mm | 833 mm | 701 mm | 741 mm | 784 mm | 819 mm |
Geometry source: Polygon first-party metric geometry table ↗ Measurements can vary by configuration, wheel size, or flip-chip position where noted by the manufacturer.
Geometry tools
Analyze a published size
The manufacturer publishes more than one geometry configuration. Velopedia analyzes each labeled state separately while treating them as one chassis in archive comparisons.
S geometry
Configuration
Archive context: Its bottom-bracket drop of 78 mm sits somewhat deeper than typical. Its reach of 369 mm sits somewhat shorter than typical. Its stack of 568 mm sits somewhat taller than typical.
Compared with 59 distinct cyclocross/gravel geometries in the Small-equivalent size cohort from model years 2022–2025 in the Velopedia archive.Want to go deeper?Open this exact published size and configuration in the Velopedia Geometry Analyzer, then complete any measurements the manufacturer did not provide.
Analyze S · Speed Gravel geometry Archive context: The chainstay of 415 mm sits toward the shorter rear-center end. Its wheelbase of 997 mm sits toward the shorter end. Its bottom-bracket drop of 79 mm sits toward the deeper-drop end.
Compared with 59 distinct cyclocross/gravel geometries in the Small-equivalent size cohort from model years 2022–2025 in the Velopedia archive.Want to go deeper?Open this exact published size and configuration in the Velopedia Geometry Analyzer, then complete any measurements the manufacturer did not provide.
Analyze S · All Road geometry M geometry
Configuration
Archive context: Its bottom-bracket drop of 78 mm sits toward the deeper-drop end. Its stack of 593 mm sits somewhat taller than typical. The head angle of 71.5° sits somewhat steeper than typical.
Compared with 63 distinct cyclocross/gravel geometries in the Medium-equivalent size cohort from model years 2022–2025 in the Velopedia archive.Want to go deeper?Open this exact published size and configuration in the Velopedia Geometry Analyzer, then complete any measurements the manufacturer did not provide.
Analyze M · Speed Gravel geometry Archive context: The chainstay of 415 mm sits toward the shorter rear-center end. Its wheelbase of 1003 mm sits toward the shorter end. The seat angle of 74.3° sits toward the steeper end.
Compared with 63 distinct cyclocross/gravel geometries in the Medium-equivalent size cohort from model years 2022–2025 in the Velopedia archive.Want to go deeper?Open this exact published size and configuration in the Velopedia Geometry Analyzer, then complete any measurements the manufacturer did not provide.
Analyze M · All Road geometry L geometry
Configuration
Archive context: Its bottom-bracket drop of 78 mm sits toward the deeper-drop end. The head angle of 71.8° sits somewhat steeper than typical. Its stack of 622 mm sits somewhat taller than typical.
Compared with 46 distinct cyclocross/gravel geometries in the Large-equivalent size cohort from model years 2022–2025 in the Velopedia archive.Want to go deeper?Open this exact published size and configuration in the Velopedia Geometry Analyzer, then complete any measurements the manufacturer did not provide.
Analyze L · Speed Gravel geometry Archive context: The chainstay of 415 mm sits toward the shorter rear-center end. The head angle of 72.1° sits toward the steeper end. Its wheelbase of 1026 mm sits toward the shorter end.
Compared with 46 distinct cyclocross/gravel geometries in the Large-equivalent size cohort from model years 2022–2025 in the Velopedia archive.Want to go deeper?Open this exact published size and configuration in the Velopedia Geometry Analyzer, then complete any measurements the manufacturer did not provide.
Analyze L · All Road geometry XL geometry
Configuration
Archive context: The head angle of 72° sits toward the steeper end. Its bottom-bracket drop of 78 mm sits toward the deeper-drop end. Its stack of 650 mm sits somewhat taller than typical.
Compared with 51 distinct cyclocross/gravel geometries in the XL-equivalent size cohort from model years 2021–2025 in the Velopedia archive.Want to go deeper?Open this exact published size and configuration in the Velopedia Geometry Analyzer, then complete any measurements the manufacturer did not provide.
Analyze XL · Speed Gravel geometry Archive context: The chainstay of 415 mm sits toward the shorter rear-center end. The head angle of 72.3° sits toward the steeper end. Its wheelbase of 1048 mm sits toward the shorter end.
Compared with 51 distinct cyclocross/gravel geometries in the XL-equivalent size cohort from model years 2021–2025 in the Velopedia archive.Want to go deeper?Open this exact published size and configuration in the Velopedia Geometry Analyzer, then complete any measurements the manufacturer did not provide.
Analyze XL · All Road geometry Parts & serviceability
Find replacement parts
ChainSRAM Rival 12-speedComponent family — verify exact version
CassetteSRAM XG-1251 12 Speed 10-44T XDRExact archived model
Bottom bracketSRAM DUB T47Named archived component — verify dimensions
More qualified parts (4)
SaddleSelle Italia Model XNamed archived component — verify exact version
CranksetSRAM Rival 1 Wide 40TComponent family — verify exact version
Rear derailleurSRAM Rival Xplr eTap AXS 12-speedComponent family — verify exact version
ShiftersSRAM Rival eTap AXS 12-speed BrifterComponent family — verify exact version
Searches use the archived manufacturer specification, not the components currently installed on a particular bicycle. Confirm the exact model, size and fit before ordering. As an Amazon Associate I earn from qualifying purchases. Velopedia may also earn from qualifying eBay purchases. Velopedia may also earn from qualifying retailer purchases. Commercial relationships do not influence Archive specifications or analysis.
Used-bike inspection
If you’re buying this bike used
Before any test ride: both brakes should stop the bike firmly and release cleanly; both wheels should run true and be securely attached; tires should have no casing damage; and the headset, handlebar, stem, cranks and pedals should have no looseness or play.
Follow the full used-bike inspection order →- FrameInspect the frame in bright light, especially around the head tube, bottom bracket, chainstays and clamped areas. Look for cracks, ripples, crushed sections or signs of a previous impact.Inspect the frame and fork →
- BrakesBoth levers should feel firm and return cleanly. Check for fluid around the levers and calipers, inspect pad thickness and contamination, and look for worn or bent rotors.Inspect the brakes →
- DrivetrainConfirm every shift-system battery charges, every shift control works and the derailleur moves cleanly across the cassette. Make sure the matching shift-system charger is included, then measure chain wear and inspect the cassette teeth.Check drivetrain wear →
- Wheels & tiresSpin both wheels and watch the rims for side-to-side or vertical movement. Check for dents, cracks, loose or uneven spokes and hub play, then inspect both tire casings for cuts, cracking or exposed threads. If it is set up tubeless, confirm both tires hold pressure and ask when the sealant was last refreshed.Check wheels and tires →
- Bottom bracketTurn the cranks slowly, feel for rough bearings and check for side-to-side play. Creaking under load deserves investigation but does not identify the source by itself.Inspect the bottom bracket and shell →
Bike-specific inspection checklist 20 checks based on 5 archived component groups Open checklistClose checklist
This checklist uses the archived equipment for this bike. It cannot confirm the condition, service history or later component changes of the example in front of you.
Identity and fit
Follow the full used-bike inspection order →Archived: 2023 Polygon Tambora G8X · Cyclocross/Gravel · Published sizes: S, M, L, XL
Frame and fork
Inspect the frame and fork →Archived: Frame: ACX GRAVEL · Fork: CARBON RIGID · Carbon Fiber
Drivetrain
Check drivetrain wear →Archived: Shifters: SRAM RIVAL ETAP AXS 12-SPEED BRIFTER · Rear derailleur: SRAM RIVAL XPLR ETAP AXS 12-SPEED · Crankset: SRAM RIVAL 1 WIDE 40T · Bottom bracket: SRAM DUB T47 · Cassette: SRAM XG-1251 12 SPEED 10-44T XDR · Chain: SRAM RIVAL 12-SPEED
Brakes
Inspect the brakes →Archived: Brakes: SRAM RIVAL HYDRAULIC DISC; Levers: SRAM RIVAL; Rotors: SRAM PACELINE 160mm CL
Wheels and tires
Check wheels and tires →Archived: Wheels: NOVATEC G24 DISC (28mm) W/ TUBELESS TAPE INSTALLED · Rims: CARBON FV H: 28 622x24 24H FOR TYRE 622-35/68 TLR · Hubs: F: NOVATEC D791 12x100mm 24H CL / R: NOVATEC D792 12x142mm 24H CL FOR XDR · Front tire: 700x40C 622x40 TLR · Rear tire: 700x40C 622x40 TLR
Controls and contact points
Archived: Headset: TOKEN TK155SP-36 W/ SEALED BEARING · Handlebar: ALLOY FLARE 16degree, W: 420mm (S, M) / 440mm (L, XL), BB: 31,8mm, R/D: 125mm, B/R: 77mm · Stem: ALLOY STEM, EXT: 90mm (S, M) / 100mm (L, XL), BB: 31,8mm, R/D: 7degree · Seatpost: CARBON, DXL: 27,.2 x 300mm (S,M,L) / 27.2 x 350mm (XL) · Saddle: SELLE ITALIA MODEL X
Before and during the test ride
Follow the full used-bike inspection order →Build relationships are limited to the archived manufacturer specifications. Confirm exact fit and standards before ordering parts or performing service.
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Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.