The Surly Lowside is your childhood BMX, all grown up and ready for big kid adventures. This bad boy is the embodiment of nostalgia, combining the playful spirit of your youth with the ambitions and dreams of adulthood. It effortlessly transitions from ripping through singletrack trails to parking it outside your beloved watering hole to going bikepacking. The Lowside is a single-speed mountain bike, a true testament to Surly’s roots since the pioneering days of the legendary 1×1 Rat Ride. Though the 1×1 had its glorious run, the Lowside triumphantly carries on its legacy, picking up right where its predecessor left off.
Imagine the thrill of pedaling through the wilderness on the Surly Lowside 27.5+, your trusted companion on bike camping adventures. This bike’s robust construction and 27.5+ wheels make it a reliable choice for navigating diverse terrains. Picture yourself cruising down forest trails, the wind in your hair, your friends at your side. As the day ends, you gather around a crackling campfire, sharing tales of the day’s ride. The Lowside isn’t just a bike; it’s your ticket to unforgettable experiences, camaraderie, and the pure joy of exploration.
Geometry & Ride Characteristics
The Surly Lowside 27.5+ features a balanced geometry that is both agile and stable. Its head tube angle is designed for steady yet responsive steering, while its relatively compact chainstay length adds a nimble quality to the bike. The wheelbase is generous enough to provide stability, especially at higher speeds or on uneven terrain. The bike’s reach and stack accommodate a broad spectrum of rider heights, ensuring a comfortable and tailored fit for most.
Riding the Surly Lowside 27.5+ offers control and freedom. The stable yet responsive head tube angle is ideal for navigating both tight trails and open roads. The bike’s agility is enhanced by its shorter chainstay length, allowing for quick turns and easy maneuverability. Meanwhile, the generous wheelbase ensures that the bike remains stable when you’re pushing the limits. This unique combination of geometric features results in a ride that is both exhilarating and reassuring, making it an excellent choice for those who value versatility.
- Head Tube Angle: The Surly Lowside 27.5+ maintains a consistent 70.0° head tube angle across all sizes. This is a balanced angle that provides a mix of stability and agility, setting it apart from bikes that vary this angle across sizes.
- Seat Tube Length: The seat tube lengths range from 316.0mm to 516.0mm, which is on the shorter side compared to many other bikes. This allows for greater standover height and maneuverability.
- BB Drop: The 55.0mm bottom bracket drop across all sizes contributes to a low center of gravity, enhancing stability. This is a feature often seen in more specialized mountain bikes.
- Chainstay Length: The chainstay length is consistently 425.0mm across all sizes, which is relatively short and contributes to the bike’s agility. This is a unique feature, as some bikes opt for variable chainstay lengths to adjust for different sizes.
- Handlebar Width: With a handlebar width of 820mm across all sizes, the bike offers greater control, a feature often found in downhill mountain bikes but less common in multi-terrain bikes.
- Wheelbase: The wheelbase ranges from 1068.0mm to 1152.0mm, which is on the longer side, offering stability at higher speeds. This is a characteristic more commonly associated with touring bikes but is a unique offering in a bike designed for varied terrains.
- Top Tube Length: The effective top tube length varies significantly across sizes, from 570.0mm to 650.0mm, allowing for a more customized fit. This level of detail is usually reserved for higher-end models.
- Stem Length and Angle: The stem length and angle are consistent across all sizes, which is not commonly seen in bikes that aim for customization in fit and feel.
vs. the Kona Unit X
The Kona Unit X is designed with a focus on versatility, featuring a 12-speed Shimano Deore drivetrain and hydraulic brakes, making it well-suited for both trail and gravel riding. Its Reynolds 520 Butted Cromoly frame offers a more compliant ride, absorbing trail chatter effectively. In contrast, the Surly Lowside 27.5+ leans more towards agility and maneuverability with its shorter chainstay length and balanced head tube angle. While the Kona Unit-X is geared towards riders seeking a multi-terrain experience with a bit more comfort, the Surly Lowside 27.5+ is for those who prioritize agility and responsiveness, at a lower relative cost.
- Kona Unit-X: Comes with a Kona Plus Fork that has 110mm spacing, designed to offer a balanced ride.
- Surly Lowside 27.5+: Equipped with a Surly Lowside Fork, specifically designed to complement the frame’s characteristics for a harmonious ride.
- Kona Unit-X: Features a 12-speed Shimano Deore drivetrain, offering a wide range of gears suitable for various terrains.
- Surly Lowside 27.5+: Comes with a single-speed setup featuring a SRAM NX 32t crankset, focusing on simplicity and low maintenance.
- Kona Unit-X: Equipped with Shimano MT410 Hydraulic brakes, known for their reliable stopping power.
- Surly Lowside 27.5+: Features Tektro Hydro M275/276 brakes, which are reliable but not as high-end as Shimano’s offerings.
- Wheel Size:
- Kona Unit-X: Designed to accommodate 29-inch wheels, which offer better roll-over capabilities.
- Surly Lowside 27.5+: Built for 27.5-inch wheels, which make for quicker handling and agility.
- Ride Feel:
- Kona Unit-X: Offers a more compliant and versatile ride, making it suitable for both trail and gravel riding.
- Surly Lowside 27.5+: Provides a more agile and maneuverable experience, optimized for quick turns and technical riding.
- Kona Unit-X: Features a more relaxed geometry, contributing to its versatility and comfort over various terrains.
- Surly Lowside 27.5+: Sports a more aggressive geometry, aimed at agility and responsiveness, making it ideal for riders who enjoy a spirited ride.
vs. the Surly Karate Monkey
The Surly Karate Monkey Rigid offers a versatile, geared riding experience suitable for a range of terrains, from singletrack to gravel. Its geometry is designed for stability and comfort, making it a go-to for longer rides and bikepacking. In contrast, the Surly Lowside 27.5+ is a singlespeed bike that prioritizes agility and responsiveness. Its lack of gears makes it a purist’s choice, focusing on a direct, unfiltered connection between rider and trail. This singlespeed setup contributes to the Lowside’s lively, nimble feel, making it ideal for quick turns and technical riding.
- Surly Karate Monkey: Features a Shimano Deore 12-speed drivetrain, suitable for a variety of terrains.
- Surly Lowside 27.5+: A singlespeed setup, offering a direct and unfiltered riding experience.
- Surly Karate Monkey: Equipped with SRAM Avid BB5 Mechanical brakes for reliable stopping power.
- Surly Lowside 27.5+: Equipped with hydraulic disc brakes for strong and consistent stopping power.
- Surly Karate Monkey: Features Surly Dirt Wizard 27.5 x 3″ tires, suitable for various terrains.
- Surly Lowside 27.5+: Equipped with Maxxis Rekon+ 27.5×2.8 tires, optimized for agility and quick handling.
- Ride Feel:
- Surly Karate Monkey: Offers a versatile, stable, and comfortable ride suitable for longer journeys.
- Surly Lowside 27.5+: Provides an agile, responsive, and lively ride, ideal for quick turns and technical riding.
- Surly Karate Monkey: Geometry is tailored for stability and comfort, making it versatile for multi-terrain riding.
- Surly Lowside 27.5+: Features a more aggressive geometry aimed at agility and responsiveness.
vs. the Bombtrack Beyond+
The Bombtrack Beyond+ is designed for long-distance bikepacking and off-road adventures, offering a stable and comfortable ride with its more relaxed geometry and wider tire clearance. It’s equipped for carrying heavy loads and features a 12-speed drivetrain. On the other hand, the Surly Lowside 27.5+ is a singlespeed bike focused on agility and responsiveness, ideal for quick turns and technical riding. While the Beyond+ is geared towards expedition-level riding, the Lowside is more suited for playful, short-distance jaunts.
- Bombtrack Beyond+: Features a 12-speed SRAM SX-EAGLE drivetrain, suitable for a variety of terrains.
- Surly Lowside 27.5+: Comes as a singlespeed, offering a straightforward and direct riding experience.
- Bombtrack Beyond+: Equipped with SRAM LEVEL hydraulic disc brakes for reliable stopping power.
- Surly Lowside 27.5+: Features Tektro Hydro M275/276 brakes, providing adequate braking for its intended use.
- Ride Feel:
- Bombtrack Beyond+: Geared towards stability and comfort, especially for long-distance and off-road riding.
- Surly Lowside 27.5+: Focuses on agility and responsiveness, ideal for quick turns and technical trails.
- Bombtrack Beyond+: Features a more relaxed geometry, designed for comfort and stability during long rides.
- Surly Lowside 27.5+: Sports a more aggressive geometry aimed at quick responsiveness and agility.
GearJunkie.com presents an insightful review of the Surly Lowside 27.5+, capturing its essence of simplicity and enjoyment on the trails. The author dives into the bike’s features and performance, stating, “The Surly Lowside is a playful, no-nonsense single-speed that’s an absolute riot to ride.” The review highlights the bike’s nimble and agile handling, making it a joy to navigate tight trails and corners. They also emphasize the Lowside’s stable and balanced ride quality, providing confidence and control over rough terrain. With its 27.5+ tires and comfortable steel frame, the Lowside delivers a comfortable and engaging ride. Overall, the review showcases the Lowside’s ability to create a fun and carefree experience on the trails, embracing the simplicity of single-speed riding with an adventurous spirit.
Singletrackworld.com presents an enthusiastic review of the Surly Lowside 27.5+, celebrating its simplicity and the joy it brings on the trails. The author delves into the bike’s features and highlights, stating, “The Surly Lowside is a pure trail bike, stripped back and single-minded.” The review showcases the bike’s nimble and playful nature, offering a unique and engaging riding experience. They appreciate the absence of suspension and multiple gears, emphasizing the Lowside’s ability to deliver a direct connection with the trail. With its 27.5+ tires, the bike provides excellent traction and a smooth ride. Overall, the review captures the essence of the Surly Lowside, celebrating its simplicity and the pure trail joy it brings to riders seeking a unique and exciting mountain biking experience.
Bikexchange.com presents an in-depth review of the Surly Lowside 27.5+, highlighting its ability to deliver a thrilling and carefree trail experience. The author explores the bike’s features and performance, stating, “The Surly Lowside is all about embracing the fun and freedom of riding without limitations.” The review emphasizes the bike’s playful and agile nature, making it a joy to ride on tight trails and technical sections. They praise the Lowside’s stability and balanced geometry, providing riders with confidence and control. With its 27.5+ tires, the bike offers excellent traction and a smooth ride over various terrains. Overall, the review captures the essence of the Surly Lowside, celebrating its ability to deliver an exhilarating and unrestricted trail adventure for riders seeking pure fun and freedom.
The Surly Lowside drivetrain includes a SRAM NX crankset with a 32t chainring, ensuring reliable power transfer. The Tektro Hydro M275/276 brakes with 160mm rotors offer reliable stopping power. The components feature a Cane Creek headset, Surly Sunrise handlebar, and a comfortable Selle Italia saddle. The wheelset consists of Novatec hubs, WTB ST i35 TCS rims, and Maxxis Rekon+ tires for excellent traction and control.
- Frame: Surly Lowside, 4130 Chromoly, Natch tubing, double-butted main triangle, TIG welded.
- Fork: Surly Lowside, 4130 Chromoly, Natch tubing, double-butted tapered fork blades, TIG welded.
- Front Derailleur: N/A
- Rear Derailleur: N/A
- Cassette: Surly 17t w/ spacer kit
- Chain: CNP1110
- Crankset: SRAM NX 32t
- Shifter: N/A
- Brakes: Tektro Hydro M275/276
- Rotors: 160mm rotors front & rear
- Headset: Cane Creek
- Stem: Sunday Freeze top load 22.2mm clamp
- Handlebar: Surly Sunrise
- Grips / Bar Tape: Velo Black
- Seatpost: 2 Bolt, 30.9mm
- Saddle: Selle Italia Black
- Seatclamp: Stainless 33.1 collar, Black
- Front Wheel: Novatec 15×110, WTB ST i35 TCS
- Rear Wheel: Novatec 12×148, WTB ST i35 TCS
- Tires:Maxxis Rekon+ 27.5 x 2.8″, 60tpi
The Surly Lowside 27.5+ is built with a robust 4130 Chromoly steel, Natch tubing frame and fork, both double-butted and TIG welded for durability. It features a 145mm rear hub spacing that is compatible with both 12 x 142mm and 12 x 148mm, and a standard 15 x 110mm front hub spacing. The bike is equipped for strong braking performance, supporting disc brakes with a 51mm I.S. and a maximum rotor size of 203mm. The head tube and steerer tube are designed with standard diameters of Ø44mm and Ø28.6mm, respectively, offering compatibility with a variety of headsets and forks. The seatpost has a diameter of Ø30.9mm, and the seat collar is Ø33.1mm. The bike can accommodate a maximum chainring of 33T for mountain setups and 36T for Boost setups, and it features a 73mm threaded bottom bracket. Tire clearance is versatile, accommodating up to 26 x 3.0″ or 27.5 x 2.8″ tires.
|Frame Construction||4130 Chromoly, Natch tubing, double-butted main triangle, TIG welded, ED coated|
|Fork Construction||4130 Chromoly, Natch tubing, double-butted tapered fork blades, TIG welded, ED coated|
|Rear Dropout Configuration||Horizontal slotted with optional vertical dropout|
|Rear Hub Spacing||“Gnot-Boost” 145mm, 12 x 142mm or 12 x 148mm (Surly axle included), 10 x 135mm with Surly 10/12 Adapter Washers (not included)|
|Front Hub Spacing||15 x 110mm (Surly axle included)|
|Rear Brake||Disc – 51mm I.S. (203mm max rotor)|
|Front Brake||Disc – 51mm I.S. (203mm max rotor)|
|Steerer Tube||Ø28.6mm (1-1/8″)|
|Crown Race||Ø30mm (1-1/8″)|
|Stock Headset Upper (S.H.I.S)||ZS44/28.6|
|Stock Headset Lower (S.H.I.S)||EC44/30|
|Front Derailleur (Clamp)||High direct mount top-pull (Ø34.9mm), 26mm offset adapter (not included) for 142 or 135mm rear hub spacing, 29mm offset adapter (not included) for 148mm rear hub spacing|
|Max Chainring (CL) ||1x (Mtn): 33T, 1x (Boost): 36T|
|Bottom Bracket||73mm threaded (1.37″ x 24TPI)|
|Tire Clearance Frame /||26 x 3.0″, 27.5 x 2.8″|
|Tire Clearance Fork ||26 x 3.0″, 27.5 x 2.8″|
|Rigid Fork Spec||420 x 47mm|
|Max Suspension Fork Length ||490 x 47mm (26 100mm)|
|Bottle Mounts Frame||1 Standard|
|Bottle Mounts Fork||N/A|
|Rack Mounts Frame||N/A|
|Rack Mounts Fork||N/A|
|Fender Mounts Frame||N/A|
|Fender Mounts Fork||N/A|
|Other Features||Internal dropper post routing compatible|
Register your purchase at Surly’s Warranty Registration.
LIMITED WARRANTY FOR THE SURLY LOWSIDE 27.5+ FRAME
This Surly product is warranted against defects in materials and workmanship for three years from the date of retail purchase of the product, subject to the limitations detailed below. Save your dated receipt for proof of purchase.
This warranty does NOT cover the following:
- Damage due to improper assembly or follow-up maintenance or lack of skill, competence or experience of the user or assembler
- Products that have been modified, neglected, used in competition or for commercial purposes, misused or abused, involved in accidents or anything other than normal use
- Installation of components, parts or accessories not originally intended for or compatible with bicycle as sold
- Damage or deterioration to the paint, surface finish, aesthetics or appearance of the product
- Normal wear and tear
- Labor required to remove and/or refit and re-adjust the product within the bicycle assembly
This limited warranty is expressly limited to the repair or replacement of a defective product, at the option of Surly, and is the sole remedy of the warranty. This limited warranty applies only to the original purchaser of the Surly product and is not transferrable. This warranty applies only to products purchased through an authorized dealer or distributor. In no event shall Surly be liable for any loss, inconvenience or damage, whether direct, incidental, consequential, or otherwise resulting from breach of any express or implied warranty or condition, of merchantability, fitness for a particular purpose, or otherwise with respect to our products except as set forth herein.
This limited warranty gives the consumer specific legal rights, and those rights and other rights may vary from place to place. This limited warranty does not affect your statutory rights.
TO THE EXTENT NOT PROHIBITED BY LAW, THESE WARRANTIES ARE EXCLUSIVE AND THERE ARE NO OTHER EXPRESS OR IMPLIED WARRANTIES OR CONDITIONS INCLUDING WARRANTIES OR CONDITIONS OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.