Description
Everything you love about the original Big Sur is back! Now sporting 20" x 4" fat tires, Big Sur Sport is smaller and lighter, but it's just as fun and performant as Big Sur 26", if not more so! This bike retains the original's class 2/3 rating (20mph and 28mph top speed using the throttle and PAS respectively), as well as its safety features, including big 203mm brake rotors, LG 21700 battery cells, and a full UL2849 certification. Equipped standard with the AIMA Comfort XL seat and an MIK rear rack, Big Sur Sport delivers the same level of power, comfort, and smoothness of its bigger brother.
Technical Specifications
MODEL

Big Sur Sport

MOTOR

750W (Rated), 48V Brushless Rear Hub Motor

THROTTLE

Throttle on Demand

DISPLAY

Color LCD, Smart Easy-to-Read Display with Backlight

SPEED

Up to 28 MPH Pedal Assist, 20 MPH Throttle Only

BATTERY

Removable Internal Lithium-ion 48V, 15Ah (720Wh) with LG M50LT 21700 cells

REAR RACK

MIK HD

SENSORS

Torque Sensor

PEDAL ASSIST

5 Levels

CHARGER

48V 3 Amp Fast Charger, about 5 Hours to a Full Charge

RANGE

Up to 60 Miles

FRAME

6061 Single-Butted Aluminum Alloy Frame with Internal Battery

WEIGHT

74 lbs. (Battery included)

PEDALS

9/16' Alloy Platform

FORK

Suspension Fork with 80mm Travel, Adjustable Preload & Lockout

WEIGHT LIMIT

400 lbs.

KICKSTAND

Included, Aluminum Alloy Kickstand

CRANKSET

160mm w/ 52T

SHIFT

Shimano 7 Speed

BRAKES

Tektro E350 Hydraulic Disc Brakes

ROTOR

203 mm

CHAIN

130 Link, 8 Speed

RIM

Double Wall Aluminum Alloy

SPOKES

Black Stainless 12G Front / 12G Rear

TUBES

Butyl Rubber

HUBS

Front Aluminum Alloy Disc Hub

TIRES

20" x 4" Puncture Resistant

SADDLE

AIMA Comfort, 280mm*270mm Saddle

SEATPOST

Aluminum Alloy, 30.4mm 2-Bolt Clamp

STEM

Threadless, 31.8mm, 7 Degree Rise, Ext 75mm

SEAT CLAMP

34.9 mm Quick Release

HANDLEBARS

Aluminum Alloy Double Wall, 31.8mm, 680mm

HEADSET

Sealed Bearing Headset

GRIPS

Ergonomic Comfort


An e-bike's battery life is influenced by several factors that can affect its maximum range. While our e-bikes can achieve up to 60 miles of range under ideal riding conditions, range figures can drop below 40 or even 30 miles without keeping these factors in mind. Here's a list of the most common factors that affect range, as well as what you can do to maximize your riding time.


Pedal Assist: Higher levels of pedal assist will allow for an easier ride, but will also draw more power from the battery. Lower assist levels are better for getting as many miles as possible out of your battery.

Average Cruising Speed: Riding slower will decrease the amount of energy you lose to wind resistance as the bike pushes you forwards through the air. Slower speeds will extend battery life.

Tire Pressure: Fat tire bikes like Big Sur and Big Sur Sport can have their tires aired down beneath the pressure rating listed on the tire for better off-road performance, but this will lead to a increase in rolling resistance, and running too low of a pressure could raise your chances of a tube failure. For most riding situations, pumping up your tires every week or two to the recommended pressure shown on the side of the tire will keep your ride safe and energy-efficient.

Load Weight: This includes both the rider's weight and the weight of any cargo you may be carrying. More weight will take more time and energy to get up to speed, negatively affecting your range. It's best to keep loads light whenever possible if you're looking to extend your range.

Terrain & Elevation: In general, riding over smooth terrain with few to no changes in elevation will give you a longer range. Hills and rough terrain can greatly impact your maximum range, especially on higher assist levels.

Wind: Wind resistance is generated as you ride through the air, but it can also be generated by, well, the wind! Riding in heavy winds, especially if it's a constant headwind, will lead to a decrease in range. However, if you can catch a tailwind, you may actually be able to steal a bit of range back, as the wind would be traveling in the same direction as you are, effectively cancelling out any wind resistance you would generate on your own.

Ambient Temperature: Riding in cold weather will impact the battery's ability to function optimally, sometimes a lot more than you might think. This is a limitation imposed by the chemistry that allows our current battery tech to work. A good rule of thumb is, if you're comfortable (temperature-wise), then the battery is comfortable too. This also goes for storing the battery if you won't be riding for an extended period of time, which leads to:

Battery Condition, Care, & Storage: As you use your e-bike's battery, its effective range will diminish over time. This is again a consequence of the Li-ion technology that powers many of our devices today, including mobile phones, laptops, electric cars, and of course, e-bikes. Li-ion batteries traditionally experience a noticeable drop in total capacity after several years of continuous use, which isn't a concern for brand-new e-bikes, but it's something to keep in mind as your e-bike ages. The battery cells that make up an e-bike battery pack like to be kept between 20% and 80% charge, and keeping the battery in this range as best as you can will prolong the battery's total lifespan.

However, if you ride frequently and/or if you ride long distances, charging to 100% is still more than safe. The Bafang battery that our bikes utilize will automatically stop charging at less than 4.2V per cell, greatly reducing the usual wear caused by fully charging the battery pack. Think of this feature as an extra level of battery capacity protection that prevents each individual cell in the battery pack from reaching its own max charge level. This means that in exchange for less than 5% of the pack's total range potential, you'll be able to retain more total battery capacity for longer compared to if the battery cells were allowed to reach their absolute maximum charge levels every time.

This practice is already commonplace in the EV industry, and it's finding its way into the PEV (personal electric vehicle) industry in e-bikes, e-scooters, and many more e-things because of the huge increase in battery lifespan it provides. Traditionally, Li-ion batteries can lose up to ~20% capacity after several years of continuous use, but this technique of limiting the battery's max charge level aims to bring that percentage down considerably.

Additionally, as mentioned above, if you'll be storing your bike without riding it for a long time (more than a month), it's best to remove the battery and keep it inside as opposed to in a garage or attic, where temperatures can fluctuate much more than what you'd see inside. If you're going to store your battery, try to charge (or discharge) it to as close to 50% charge as possible first, which is where the battery likes to sit if it won't be used for a while. Keeping the battery near 50% will minimize the degradation it undergoes during storage.