Rear tire: 700C×50.
Velopedia Bicycle Archive
2025 Kona Ouroboros
Original specifications: geometry for 6 published sizes.
Planning to sell? Draft your listing
At a glance
Archive #900001002- Model year
- 2025
- Category
- Gravel & Cyclocross
- Original MSRP
- $2,099.00
- Sizes
- 48, 50, 52, 54, 56, 58
- Colors
- Gloss Metallic Turismo Olive w/ Porsche Olive Decals
- Geometry
- 6 manufacturer sizes
- In this record
- 20 specifications · 8 archived images · original MSRP · geometry
Original buildAluminum
Frameset
| Frame Construction | Kona 6061 Aluminum Butted |
|---|---|
| Frame Material | Aluminum |
| Fork | Suntour GVX32 40mm travel, Tapered, 100x12mm |
Drivetrain
| Shifters | Microshift Sword left dropper/brake and right brake/shifter |
|---|---|
| Rear Derailleur | Microshift Sword Long Cage w/Clutch |
| Crankset | Microshift Sword; Chainring: 40t 10sp narrow-wide |
| Bottom Bracket | Prowheel PF86.5 |
| Cassette | Microshift Sword 11-48t 10spd |
| Chain | KMC X10 |
Brakes
| Brakes | Brake Calipers: TRP Spyre C; Front Brake Rotor: TRP 180mm; Rear Brake Rotor: TRP 180mm; Brake Levers: Microshift Sword |
|---|
Cockpit & Contact Points
| Headset | FSA No.57B |
|---|---|
| Handlebar | Kona Gravel 20-degree flare, 48: 440mm; 50: 460mm; 52-54: 480mm; 56: 500mm; 58: 520mm |
| Stem | Kona Gravel 6-degree rise, 48-52: 50mm; 54-58: 60mm |
| Saddle | WTB Volt |
| Seatpost | TranzX Dropper +RAD Internal 31.6mm 125mm travel |
Wheels & Tires
| Hubs | (F) Formula 100x12mm 6-bolt / (R) Formula 142x12mm 6-bolt, standard road 11sp freehub body |
|---|---|
| Rims | WTB ST I27 TCS 2.0 |
| Spokes | Stainless Black 14g |
| Front Tire | Maxxis Ravager EXO TR 700x50c |
| Rear Tire | Maxxis Ravager EXO TR 700x50c |
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 measurements6 sizes · 15 measurements
| Measurement | 48 | 50 | 52 | 54 | 56 | 58 |
|---|---|---|---|---|---|---|
| Seat tube | 410 mm | 410 mm | 455 mm | 455 mm | 500 mm | 535 mm |
| Top tube | 532 mm | 547 mm | 559 mm | 578 mm | 595 mm | 616 mm |
| Head tube | 116 mm | 132 mm | 148 mm | 172 mm | 193 mm | 225 mm |
| Head-tube angle | 68.7° | 68.7° | 68.7° | 68.7° | 68.7° | 68.7° |
| Seat-tube angle | 74.2° | 73.7° | 73.2° | 72.7° | 72.2° | 71.7° |
| Chainstay / rear center | 445 mm | 445 mm | 445 mm | 445 mm | 445 mm | 445 mm |
| Wheelbase | 1060 mm | 1071 mm | 1082 mm | 1096 mm | 1108 mm | 1124 mm |
| Bottom-bracket drop | 69 mm | 69 mm | 69 mm | 66 mm | 66 mm | 66 mm |
| Bottom-bracket height | 296 mm | 296 mm | 296 mm | 299 mm | 299 mm | 299 mm |
| Reach | 372 mm | 377 mm | 382 mm | 386 mm | 391 mm | 396 mm |
| Stack | 566 mm | 581 mm | 598 mm | 616 mm | 636 mm | 666 mm |
| Standover height | 725 mm | 730 mm | 769 mm | 777 mm | 814 mm | 848 mm |
| Fork offset / rake | 51 mm | 51 mm | 51 mm | 51 mm | 51 mm | 51 mm |
| Front center | 624 mm | 635 mm | 646 mm | 659 mm | 671 mm | 687 mm |
| Fork length / axle-to-crown | 435 mm | 435 mm | 435 mm | 435 mm | 435 mm | 435 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

Vittoria Terreno Mix G2.0 TNT Tubeless Tire Anthracite/Black, 700x50
700x50c
Replacement option

SDG Components Tellis V2 Dropper Post Black, 31.6mm, 125mm
Replacement option
More parts (6)Fewer parts
Chainring: 40t 10sp narrow-wide
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.
Service essentialsQuick reference before buying parts
Archived specifications for reference. Check the fitted parts before ordering.
- Front tire
- Maxxis Ravager EXO TR 700x50cCheck: Verify the fitted tire’s size marking and rim type.
- Rear tire
- Maxxis Ravager EXO TR 700x50cCheck: Verify the rear size; it may differ from the front.
- Drivetrain
- 10-speedCheck: Match the installed drivetrain family, not just its speed count.
- Seatpost diameter
- 31.6 mmCheck: Read the post’s diameter marking; seat-clamp size differs.
- Bottom bracket / shell
- Prowheel PF86.5Check: Verify shell type and width, crank interface, and spindle length or spacers.
Bike-specific inspection checklist 20 checks based on 6 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: 2025 Kona Ouroboros · Cyclocross/Gravel · Published sizes: 48, 50, 52, 54, 56, 58
Frame and fork
Inspect the frame and fork →Archived: Frame: Kona 6061 Aluminum Butted · Fork: Suntour GVX32 40mm travel, Tapered, 100x12mm
Suspension
Evaluate the suspension →Archived: Fork: Suntour GVX32 40mm travel, Tapered, 100x12mm
Drivetrain
Check drivetrain wear →Archived: Shifters: Microshift Sword left dropper/brake and right brake/shifter · Rear derailleur: Microshift Sword Long Cage w/Clutch · Crankset: Microshift Sword; Chainring: 40t 10sp narrow-wide · Bottom bracket: Prowheel PF86.5 · Cassette: Microshift Sword 11-48t 10spd · Chain: KMC X10
Brakes
Inspect the brakes →Archived: Brakes: Brake Calipers: TRP Spyre C; Front Brake Rotor: TRP 180mm; Rear Brake Rotor: TRP 180mm; Brake Levers: Microshift Sword
Wheels and tires
Check wheels and tires →Archived: Rims: WTB ST i27 TCS 2.0 · Hubs: (F) Formula 100x12mm 6-bolt / (R) Formula 142x12mm 6-bolt, standard road 11sp freehub body · Front tire: Maxxis Ravager EXO TR 700x50c · Rear tire: Maxxis Ravager EXO TR 700x50c
Controls and contact points
Archived: Headset: FSA No.57B · Handlebar: Kona Gravel 20-degree flare, 48: 440mm; 50: 460mm; 52-54: 480mm; 56: 500mm; 58: 520mm · Stem: Kona Gravel 6-degree rise, 48-52: 50mm; 54-58: 60mm · Seatpost: TranzX Dropper +RAD Internal 31.6mm 125mm travel · Saddle: WTB Volt
Before and during the test ride
Follow the full used-bike inspection order →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.
Gallery8 images
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.




