Velopedia Bicycle Archive
Surly Lowside - Blue Monday
Original specifications: 27.5"; 26" wheels · 28 lb 1 oz for Medium published weight · geometry for 5 published sizes.
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At a glance
- Model year
- Not published by manufacturer
- Category
- Mountain
- Original MSRP
- $1,799.00
- Sizes
- XS, S, M, L, XL
- Weight
- 28 lb 1 oz for Medium
- Geometry
- 5 manufacturer sizes
- In this record
- 20 specifications · 8 archived images · original MSRP · geometry
- Archive ID
- 900000933
Original buildSteel · 27.5"; 26"
Frameset
| Frame Construction | Surly Lowside - 4130 Chromoly, Natch tubing, double-butted main triangle, TIG welded, E.D. coated |
|---|---|
| Frame Material | Steel |
| Fork | Surly Lowside - 4130 Chromoly, Natch tubing, double-butted tapered fork blades, TIG welded, E.D. coated |
| Fork Material | Steel |
Drivetrain
| Crankset | SRAM NX Eagle, 32t |
|---|---|
| Bottom Bracket | SRAM PowerSpline, BSA, 73mm |
| Cassette | Surly 17T Cog w/ Spacer Kit, silver |
| Chain | KMC X9 |
Brakes
| Brakes | Brake Calipers: Tektro HD-M275/276, 2-piston; Brake Levers: Tektro HD-M275/276; Rotors: Tektro 160/160mm, 6-Bolt |
|---|
Cockpit & Contact Points
| Headset | FSA Orbit ITA, Silver |
|---|---|
| Handlebar | Surly Sunset (Painted to match frame) |
| Stem | Sunday Freeze Stem Top-Load, Silver |
| Saddle | WTB Volt Medium, silver rails |
| Seatpost | Promax SP-2019, Silver |
Wheels & Tires
| Hubs | (F) Novatec 15 x 110mm, silver / (R) Novatec 12 x 148mm, silver |
|---|---|
| Rims | WTB ST i35 TCS 2.0 27.5", 32h |
| Spokes | 14g stainless, silver |
| Front Tire | Maxxis Rekon+ 27.5" x 2.8", 60 TPI, tan sidewalls, tubeless-ready, WTB TCS Sealant included |
| Rear Tire | Maxxis Rekon+ 27.5" x 2.8", 60 TPI, tan sidewalls, tubeless-ready, WTB TCS Sealant included |
| Wheel Size | 27.5"; 26" |
Geometry
Frame measurements by size.
Frame diagram
Select an available measurement to locate it on the frame.
All geometry measurements5 sizes · 16 measurements
| Measurement | X-Small | Small | Medium | Large | X-Large |
|---|---|---|---|---|---|
| Seat tube | 316 mm | 366 mm | 416 mm | 466 mm | 516 mm |
| Effective top tube | 570 mm | 590 mm | 610 mm | 630 mm | 650 mm |
| Head tube | 110 mm | 125 mm | 140 mm | 155 mm | 170 mm |
| Head-tube angle | 70° | 70° | 70° | 70° | 70° |
| Seat-tube angle | 74° | 74° | 74° | 74° | 74° |
| Chainstay / rear center | 425 mm | 425 mm | 425 mm | 425 mm | 425 mm |
| Wheelbase | 1068 mm | 1089 mm | 1110 mm | 1131 mm | 1152 mm |
| Bottom-bracket drop | 55 mm | 55 mm | 55 mm | 55 mm | 55 mm |
| Reach | 414.5 mm | 429.3 mm | 445.3 mm | 461 mm | 477 mm |
| Stack | 542.2 mm | 560.3 mm | 574.4 mm | 588.5 mm | 602.5 mm |
| Standover height | 700 mm | 729 mm | 762 mm | 792 mm | 823 mm |
| Fork offset / rake | 47 mm | 47 mm | 47 mm | 47 mm | 47 mm |
| Fork length / axle-to-crown | 420 mm | 420 mm | 420 mm | 420 mm | 420 mm |
| Crank length | 165 mm | 165 mm | 165 mm | 170 mm | 170 mm |
| Stem length | 48 mm | 48 mm | 48 mm | 48 mm | 48 mm |
| Handlebar width | 820 mm | 820 mm | 820 mm | 820 mm | 820 mm |
Dimensions as recorded.
Gearing
Lower gears help on climbs. Higher gears suit higher speeds.
RPM = pedal turns per minute.
Speed unavailable: wheel or tire size is missing or unclear.
How it works
Ratio = chainring teeth ÷ rear sprocket teeth. A 400% range means the highest ratio is four times the lowest.
Speeds are estimates from tire size and pedal cadence. Actual speeds vary.
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: Surly Lowside - Blue Monday · Mountain · Published sizes: XS, S, M, L, XL
Frame and fork
Inspect the frame and fork →Archived: Frame: Surly Lowside - 4130 Chromoly, Natch tubing, double-butted main triangle, TIG welded, E.D. coated · Fork: Surly Lowside - 4130 Chromoly, Natch tubing, double-butted tapered fork blades, TIG welded, E.D. coated · Steel
Drivetrain
Check drivetrain wear →Archived: Crankset: SRAM NX Eagle, 32t · Bottom bracket: SRAM PowerSpline, BSA, 73mm · Cassette: Surly 17T Cog w/ Spacer Kit, silver · Chain: KMC X9
Brakes
Inspect the brakes →Archived: Brakes: Brake Calipers: Tektro HD-M275/276, 2-piston; Brake Levers: Tektro HD-M275/276; Rotors: Tektro 160/160mm, 6-Bolt
Wheels and tires
Check wheels and tires →Archived: Wheel size: 27.5"; 26" · Rims: WTB ST i35 TCS 2.0 27.5", 32h · Hubs: (F) Novatec 15 x 110mm, silver / (R) Novatec 12 x 148mm, silver · Front tire: Maxxis Rekon+ 27.5" x 2.8", 60 TPI, tan sidewalls, tubeless-ready, WTB TCS Sealant included · Rear tire: Maxxis Rekon+ 27.5" x 2.8", 60 TPI, tan sidewalls, tubeless-ready, WTB TCS Sealant included
Controls and contact points
Archived: Headset: FSA Orbit ITA, Silver · Handlebar: Surly Sunset (Painted to match frame) · Stem: Sunday Freeze Stem Top-Load, Silver · Seatpost: Promax SP-2019, Silver · Saddle: WTB Volt Medium, silver rails
Before and during the test ride
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Gallery8 images
Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.



