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Lvbu KD Series Ebike kit

Saddle bag battery with just 2 cable connections, more flexible to fit

Assist range from 90km to 120km / Wired thumb throttle / Induction cut off system / Built in Gyroscope / Road Slope degrees detection / All Terrain Application / Lost bike tracking

  • (optional)
  • (optional)
  • 8 minutes

    Quick installation

  • 16-29inch

    Multiple wheel sizes

  • 5 modes

    Smart assistance modes

  • 32km/hour

    Maximum speed

  • 250w

    High-speed brushless motor

  • 2 control ways

    Smart Assist System / Throttle

Product Specification

    Model
    KD30S / KD40S
    Battery capacity
    36V 9Ah / 36V 12AH
    Cell quantity
    30 cells / 40 cells
    Charging time
    4.5H / 6.0H
    Battery type
    18650 power lithium ion battery
    Charger
    AC110V-AC220V, DC42V 2A (EU/US/UK/AU plug)
    Assist range
    90km / 120km

    *The assist range is tested under conditions: 60kg rider, ouside temperature 25℃,no wind, 50% assist level under manual mode, tires with enough air pressure, riding on flat level road without stop.

    Maximum speed
    32km/h
    Rim size
    12"/14"/16"/ 20" / 24" / 26" / 27.5" / 29" / 700C (28")
    Rated power
    250W/350W
    Motor structure
    Gear drive
    Motor efficiency
    >80%
    Max torque
    30N.m
    Product dimensions
    Motor Weight
    2.6kg/2.55kg/3.25kg/3.45kg/2.7kg (250w Front / 250w Rear/350w Front/350w Rear/ 250w Rear with torque sensor)
    Battery Weight
    1.74 kg /2.22 kg ( KD30S/ KD40S)
    Controller Weight
    0.34 kg
    Package dimensions
    71*71*22cm

Small size controller box makes it's easy to be hidden.

Makes less change Obtains great joy

Can you find out where the controller is?

INSTALLATION REQUIREMENTS

Just 3 steps to transform your bike into a smart ebike.

Fits every size bikes

KD series kit fits all standard bikes. It has mulptiple wheel sizes from 16" to 29" and 700C

High quality 18650 lithium battery

EV lithium-ion battery cell with internal resistance as low as 18mΩ, capacity of 2900mA, 3C high-rate discharge. The 18650 power lithium battery offers consistency, high energy density, and faster charge/discharge performance. Tried and tested over time, 80% capacity remains after 1000 cycles, making this high-quality lithium battery’s lifetime more than 5 years.

Using high-performance and high-safety BMS battery protection system

  • Over-discharge protection
  • Overcurrent protection
  • Temperature protection
  • Overcharge protection
  • Short circuit protection
  • Battery balance protection

250W high speed brushless permanent magnet motor

Small size, light weight, high efficiency, stable operation, long lifetime
Planetary gear and clutch:It's easy to ride even when the battery is dead.

250W
Rated power
500W
Peak power

Power :  250W
Voltage :  36V
Structure :  Gear Drive
Efficiency :  >80%
Maximum torque :  30N.m

Micro Power system

9 years of research and development has gone into creating a versatile and cost-effective product for cyclists. The micropower system offers intelligent assistance with induction brakes that have a response time of 10ms. The system can sense the speed, acceleration and road slope, it will help you automatically when you pedal.


Uphill
Automatically increase power

Downhill
Automatically cut off power

ARM Cortex-M3 main chip

With 6-axis gyroscope motion processing chip
Configure low-power Bluetooth 4.0, low-power power management chip
6 high-sensitivity speed-measuring magnets for precise speed measurement

5 smart assist modes

We have spent 9 years on developing and optimizing the assist system. The assist system is based on the speed, acceleration, the road slope, and also the assist level that you set in the APP or on the Bluetooth display, calculating out the power you need. It will assist you automatically when you pedal. And we will keep on optimizing the system and publishing it from time to time. You will be able to update the system by the APP.

  • Leisure mode
  • Commute mode
  • Exercise mode
  • Manual mode
  • Climbing mode

Dedicated APP provides you wonderful cycling experience

You can use the APP to control the wheels, upgrade the firmware, set the assist mode, set the assist level, calibrate the gyroscope angle, and detect the fault. And also you can check the speed, temperature, power, mileage, etc.

Speed up to 32km/h
Speed limitation is settable in the APP.

The default maximum speed is 25km/h, you can set the speed limitation to Ultimated speed in the APP.


Lost bike tracking function: You can report lost when your bike is stolen.

After you report lost, once the thief tried to connect the wheel with the APP, the system will locate the mobile phone, disable the motor immediately and upload the information to the server.

IP65 waterproof grade

IP65 waterproof grade makes you ride freely in the rain.

Coated Saddle Battery Bag

Bag battery is easy to remove

Charging time: 3-4 hours
You can take off the battery to charge easily.

Packing list

1. Motor wheel 2. Battery 3. thumb throttle 4. Charger 5. Accessories 6. Manual

Welcome to send us your enquiry, we will contact you as soon as possible
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FAQ

Can I buy a spare battery?

Yes. We find the vast majority of people don’t need a spare, but if you want to go on very long bike rides you can double your range by charging a spare battery and taking it with you. You can purchase a spare battery here.

Do I have to use the thumb controller?

No. The thumb controller is your choice. We find that some of our customers prefer not to use the thumb controller and that’s fine, the bike will automatically work on the pedal assist mode.

What if I don’t know my wheel/tyre size?

This is a common question.  Your tyre size should be written on the side of your tyre.  There will be a series of numbers showing the diameter and width.  It will look something like this: 700c x 38.  Occasionally different cycle manufacturers will use a different scale.  If you have any problems working out your tyre size, please call us on +86 199 7018 0785.  Alternatively, you can email us a picture of the writing on your tyre to miya@lvbu.tech

Does the kit accommodate hydraulic brakes?

Yes it does. The kit will automatically sense when the brakes are applied and cuts the power to the motor.

Will Lvbu kit fit my bike ?

LVBU kit will fit most bikes except thru axle. 

What is the difference between KD30S and KD40S

The only difference between KD30S and the KD40S is the capacity of the battery pack. KD40S has 40 cells battery pack (36V 11.6Ah) and KD30S has 30 cells of battery (36V 8.7Ah), everything else is the same. 

How much does the kit weigh?

The entire kit weights 6.5kg/7kg.

How long is the lifetime of the battery?

Lvbu ebike kits use EV 18650 lithium-ion battery cells with class A quality. Working with our own BMS system, the lifetime of the battery is very high. 80% capacity remains after 1,000 cycles. So normally it can last 5 years.

*Note: The definition of one cycle is that charge the battery from 0 to 100% and discharge it fully. For example, if you charge the battery from the 0 to 50% and discharge it to 0, that is 0.5 cycle.

How to connect Lvbu kit with the APP?

Open the APP and allow all the permissions that the APP asks for. And tap the magnified glass icon on the right top of the APP to search for the Bluetooth address. Select the right address of your kit in the list to connect.
 
*Note: Please connect the kit in the APP, don’t connect it in the operation system of the phone. You don’t need to input any pin to connect. And please make sure all permissions are allowed and the kit is not connected to other devices. The kit can just connect to only one device at the same time.

How does Lvbu wheel recognize uphill?

Lvbu wheel has a built-in six-axis gyroscope, which can sense the slope of the road such as uphill and downhill. But if you want to detect the slope of the road correctly, you must calibrate the gyroscope angle on the level ground first. The way how gyroscope works is as below: 

  • The purpose of calibrating the gyroscope angle is to give the gyroscope a horizontal reference, telling the gyroscope that the current angle is level, so that the gyroscope can detect the slope. 
  • If the gyroscope is calibrated on a downhill road, the gyroscope will regard the downhill road with a certain angle as a horizontal road, but when the bike is on a level road, the gyroscope will sense it as an uphill, in that case the motor will always provide assistance; 
  • If the gyroscope is calibrated on an uphill road, the gyroscope will treat this uphill road as a horizontal road. And when the bike is on a level road, the system will shut down the motor because the gyroscope sense the level road as a downhill road by mistake.

    Therefore, you must calibrate the gyroscope on a level ground, otherwise there will be problem with the assist system.
How to connect LVBU ebike kit with Bluetooth display?

BTC02 Display Connect Method:

  • Please turn off or disconnect the Bluetooth connection on your phone before the Bluetooth display connects to the LVBU Wheel. The wheel cannot connect to more than one device at the same time; 
  • Press the power button of the Bluetooth display to turn it on. Then press the power button three times continuously. The display will search for the Bluetooth address of the lvbu ebike kits nearby; 
  • After the display finishes the search, press the up and down keys to select the right address of your kit and press the power button to connect.

DW03 Display Connect Method:

  • Open the APP and connect it with the Lvbu ebike kit
  • Press the power button of the Bluetooth display to turn it on.
  • Tap the "device" icon at the bottom right in the front page of the APP-->Tap "Add Device"--> Select the display in the list to connect.
What is lvbu kit warranty policy?

For battery, motor and controller, we provide one year warranty.

Do I need a mobile phone to operate my bike?

No, using your mobile phone is your choice. If you want, you can download the Wepower app, where you can set the pedal assist mode, see the speed, temperature, battery level and mileage covered. But this is entirely optional, and the bike will function perfectly without it.

My bike has disc brakes – will the kit still work?

Yes, the kit fits both V brakes (sometimes called rim brakes) and disc brakes.

How does the pedal assist work?

The kit has an “intelligent assist control module” which works in conjunction with a gyroscope calculating the power you need.  It will assist you automatically when you are pedalling.  The motor will not work until the speed reaches 5km/h. The system will increase the power when you go uphill and will shut down the motor when you are going downhill.  When you brake, the system can detect the decrease of the speed, and will stop the motor.

If you push the thumb throttle the bike will be fully driven by electric power, but when you release it the pedal assist system will kick in again automatically.

How long does the battery take to charge?

Approximately 4.5hours/6 hours at the mains.  The battery comes with a charger.

Is the import taxes included in the price? Do I need to pay taxes when I receive the ebike kit?

If the delivery address are in the countries below then you don't need to pay any taxes or VAT:

United Kingdom, United States, Canada, Australia, Russia, France, Germany, Italy, Spain, Sweden, Denmark, Ireland, Belgium, Netherlands, Czech, Republic, Austria, Portugal, Slovakia, Slovenia, Hungary, Bulgaria, Estonia, Greece, Poland, Lithuania, Finland, Latvia, Croatia, Ukraine.

How does Lvbu kit system work ?
  • Lvbu assist system is an intelligent assist system which can calculate out and provide the proper power based on the speed, acceleration, the slope of the road, and the assist level set in the APP or display. It will provide proper power automatically when you pedal. The motor will not work until the speed reaches 5 km/h. 
  • It will increase the power when it senses the acceleration is positive and decrease the power when it is minus. The system will also increase the power when going uphill and shut down the motor when going downhill. And the kit can also be controlled by the optional wireless thumb throttle. When you push the throttle, the bike will be fully driven by electric power, but when you release it the assist system will kick in again automatically. The introduction of the 5 assist modes is as following:
     * Manual mode: The most often used mode. The users can set a proper assist grade from 0 to 99 for themselves. 0 stands for no assist while 99 stands for the strongest assist. Under the manual mode the user can use the optional wireless display to set the assist grade instead of using smart phone. After setting the assist grade, the wheel will assist automatically.
     * Commute mode: Under this mode, the wheel will have relatively strong assist power all the time. The output curve of the assist grade is as shown above. It is similar to an assist grade of 60% in the manual mode.
     * Leisure mode: The assist power output is as the curve above. It is a curve similar to a damping ratio. Half an hour is a cycle. At the end of the cycle, the assist will become stronger.
     * Exercise mode: This mode has a small assist output. One cycle is also half an hour. After about 10 minutes, the assist power output will become stronger in the rest of the cycle.
     * Climbing mode: The wheel provides a certain assist grade only if the road is uphill that above a certain slope angle. The assist grade and the slope angle can be set in the APP. For example, when you set 2 degrees and an 80 assist grade, the wheel can give you an 80 assist grade when you are on the road with slope angle above 2 degrees.

     Note: Lvbu's intelligent assist system can be upgraded by the APP. We will keep optimizing the algorithm and publishing the new firmware.
Is Lvbu kit compatible with V brake?

Yes, Lvbu kit is compatible with rim brakes and disc brakes.

And a free new disc can be provided if you need.

Is it safe to use the front wheel drive?

Yes, it’s safe to use the front wheel drive. 

The power of the front wheel motors those lvbu ebike kit use are between 250w to 350w, so there is no safety problem. Actually, there are some advantages to using front motor drive: 

 It is more efficient to pull the bike compared to push the bike.

 The front motor will balance the weight of the front wheel with the rear wheel to make it stabler

 It is much easier to install the front wheel than the back wheel.

What are the functions of the APP?

The APP has two main kinds of functions as following: 

  • Set the parameters:
    ①Search and bind the Lvbu ebike kit: You need to search and bind the kit with the APP when you use it first time.
    ②Calibrate the gyroscope angle: The gyroscope angle must be calibrated after the first time you attach or reattach the kit to your bike.
    ③Set the assist mode or adjust the assist level.
    ④Set over-speed alarm.
    ⑤Set the maximum assist speed (speed limit).
    ⑥Lost report.
    ⑦Firmware upgrade.
    ⑧Restore factory settings.
    ⑨Set the wheel weight, load, wheel size, etc. ...
     After adjusting and setting the parameters, the system will automatically save values instantly.
  • Show cycling data:
    ①Riding speed
    ②Riding mileage: total mileage, current mileage, uphill mileage, etc.
    ③Kit model
    ④Bluetooth address
    ⑤APP version
    ⑥User instructions ...
    We are keeping optimizing the APP all the time, the new version of the firmware and the APP will be released from time to time, you can update it anywhere with the network of your mobile phone.

Do I have to connect to the APP while riding?

No, you don’t have to connect the kit with the APP when you are riding. The assist system is written in the controller, not in the APP. But before the first time you use it, you must calibrate the gyro angle for the bike.
You can set the assist grade in the APP and put your phone in your pocket. The kit will provide proper assist power for you automatically.

What is the range of the battery?

The battery is a high quality power lithium-ion battery, 36V, 9/12AH. The range is approximately90/120 km+. But that does depend on many various factors, including terrain, slope, your weight and how much you pedal and your level of assist.

Do you have a local dealer or oversea warehouse?

Yes, we have oversea warehouse in Europe.

And for some countries, we do have local dealers. 

363 REVIEWS - KD series Ebike Conversion Kit
Christopher Myers
Italy , 4/20/2026
I waited a long time for my kit. When it arrived everything was there and it was easy to fit. I used it a few times now and I must admit I’m impressed. My bike is quite light and I only use the electric assist on hills. It’s very good. So fair enough the wait was worth it and it’s a good product.
Model: KD30S 250W 9Ah Rear, KD30S Rear wheel ebike kit
Size: 26", 26 inch rim with tyre
Color: Black, Black
bromjohn
United States of America , 4/16/2026
I didn't like going slowly up hills while my wife zoomed up on her kit ebike. I got the same setup with the display control. I'd done one before, so fitting was easy, worked well on day one. As another reviewer commented - a 20+ year old bike rejuvenated, and used much much more.
Model: KD40S 350W 12Ah Front, KD40S Front wheel ebike kit
Size: 27.5", 27.5 inch rim with tyre
Color: Black, Black
Kenneth Davidson
United States of America , 4/15/2026
I have now had two weeks of using the hub motor kit on my 24 year old bike. The kit has rekindled my interest in cycling and exceeded my expectations. I liked the simplicity of fitting the quality of the components and the online help available. Longer bicycle rides are now a realistic possibility once I fully adjust to the amazing transformation which the motor kit has produced. I purchased the smaller saddle battery and whilst i now realise that the 12AH would have been a better buy, I suppose I'll get more exercise. If anyone is looking to upgrade to electric cycling then LVBU ebike kit is definitely worth considering. There are other ebike conversion kits available but LVBU ticks all the boxes for me.
Model: KD30S 250W 9Ah Front, KD30S Front wheel ebike kit
Size: 24", 24 inch rim with tyre
Color: Black, Black
Siobhan Grieve
Canada , 4/13/2026
The kit took a bit longer to come probably due to the longer shipping route, but was well worth the wait. Installation was straightforward.. I have done 3 rides so far total 100 kilometres and still have 3 bars on the battery level indicator. The electric motor helps with increasing the length of my rides. It will be even more useful in the winter for long rides into the wind. It enables me to choose the intensity of my workouts.
Model: KD30S 350W 9Ah Front, KD30S Front wheel ebike kit
Size: 26", 26 inch rim with tyre
Color: Black, Black
A Mort
France , 4/10/2026
My query was dealt with in a timely manner by a competent customer service advisor who was able to resolve my query quickly.
Model: KD30S 250W 9Ah Rear, KD30S Rear wheel ebike kit
Size: 451-20”, 20"
Color: Black, Black
Peter Hermann
United States of America , 4/8/2026
Good kit - does the job. I first had a hitch with a bent pin in the battery connector which I found with the aid of a lens. We'll see.
Model: KD40S 250W 12Ah Front, KD40S Front wheel ebike kit
Size: 700C (28"), 28 inch rim with tyre
Color: Black, Black
Horst
Korea , 4/2/2026
Had the kit and I love it. I have had no faults builing it or riding it. I been out on the bike every day and would definitely recommend if looking to get and old bike new life..
Model: KD30S 350W 9Ah Front, KD30S Front wheel ebike kit
Size: 406-20", 20 inch rim with tyre
Color: Black, Black
Claire
United States of America , 4/1/2026
Although it did take a while to get (which the company is up front about) the kit was very easy to install. We put it on my sons road bike and it works even better then expected. I can easily ride his bike at 30 kph and it does make hill a breeze. Great product and in my opinion well worth the cost. (And wait)
Model: KD40S 350W 12Ah Front, KD40S Front wheel ebike kit
Size: 27.5", 27.5 inch rim with tyre
Color: Black, Black
Jad Abi Akar
Austria , 3/31/2026
I upgraded an older 7-speed 28” Cresent bike with this kit. I placed the battery and cables in the bike basket. I am very satisfied, easy to install, easy to use and very pleasant to ride with.
Model: KD30S 250W 9Ah Front, KD30S Front wheel ebike kit
Size: 700C (28"), 28 inch rim with tyre
Color: Black, Black
Robert McGrath
Canada , 3/30/2026
I do love the conversion kit but after being in business for a number of years they should be able to do a much better job of getting the kit out in a shorter time frame. It was also more complex than expected to install the kit. That being said, I do like that I can use my bike with or without the kit and it has good power.
Model: KD40S 350W 12Ah Front, KD40S Front wheel ebike kit
Size: 27.5", 27.5 inch rim with tyre
Color: Black, Black
Matt
United States of America , 3/27/2026
lvbu is cool. Friendly customer service. Rao had helped me to sort out an issue I had with my power pack. I got the kit in 2020, and had 1 issue only! I love my bike. Highly recommended!
Model: KD30S 350W 9Ah Front, KD30S Front wheel ebike kit
Size: 26", 26 inch rim with tyre
Color: Black, Black
Fran Three
France , 3/25/2026
Very impressed! As a senior, the weight of nearly all e-bikes are 50 pounds and above is too heavy to lift onto a bike rack! With the modification, I’m still able to enjoy my light road bike but as an ebike! (And at a very reasonable price!). I show it off to the members of my bike club and other friends. I suggest the LED display and the throttle as needed options.
Model: KD30S 250W 9Ah Front, KD30S Front wheel ebike kit
Size: 26", 26 inch rim with tyre
Color: Brown, Brown
PAULS
United Kingdom , 3/23/2026
After not using my bike for a year, I brought it back into use only to experience a very noisy motor when pedal power was applied. Support (Rao) gave me instructions on how to adjust the Cassette set. The motor is now making a more normal sound and the bike is good to use. Responses all came withing 24 hours. Thanks
Model: KD40S 250W 12Ah Rear Motor with Torque Sensor, KD40S 250W Rear Motor with Torque Sensor
Size: 700C (28"), 28 inch rim with tyre
Color: Black, Black
michael veasley
United States of America , 3/20/2026
I absolutely LOVE my new e-bike. Was a single speed commuter for well over 10 years. Now, my bike is electric! Took a little time to get used to how to get the most out of it - for example, keeping it on 50% instead of ‘99%' for most of my journey, and only using 90% above for especially hard hills. I would love if they also designed some lights for the kit. That would make a lot of sense! Other than that, I also upped the size of my crank chain ring. Easy gear no longer needed! All in all, I’m very happy that I made the purchase ;)
Model: KD40S 250W 12Ah Rear Motor with Torque Sensor, KD40S 250W Rear Motor with Torque Sensor
Size: 29", 29 inch rim with tyre
Color: Black, Black
Robin Martin
United Kingdom , 3/19/2026
KD40S Pros: * Easy to install * Good battery capacity * Works well * The response time from support was surprisingly short Cons: * Long shipping time (one month more) * Cable is little longer for my bike (20")
Model: KD40S 250W 12Ah Front, KD40S Front wheel ebike kit
Size: 406-20", 20 inch rim with tyre
Color: Black, Black
Laurence Robertson
France , 3/18/2026
Took 2 months to arrive but worth it. The wife loves it. Now she can keep up with me
Model: KD40S 250W 12Ah Front, KD40S Front wheel ebike kit
Size: 26", 26 inch rim with tyre
Color: Brown, Brown
Tord
Denmark , 3/16/2026
I converted a 20 year old Crescent 24'' bike. Very satisfied, easy to use and good instructions.
Model: KD30S 250W 9Ah Front, KD30S Front wheel ebike kit
Size: 24", 24 inch rim with tyre
Color: Black, Black
Daniel Dorrington
United States of America , 3/9/2026
Bought one for my daughter a few years ago and she always raved about it. So treated myself . I like the boost, it’s made me remember how much I enjoyed cycling as a kid and as a 61 year-old I’m rediscovering the freedom of travel without the car. Thank you. Carry on with your exceptional customer service (and product!), consumers notice!!
Model: KD40S 350W 12Ah Front, KD40S Front wheel ebike kit
Size: 700C (28"), 28 inch rim with tyre
Color: Black, Black
Phil Michael Pugh
Canada , 3/6/2026
Range seems good and the power delivery is smooth with enough torque. My one grip would be that I’d like a way of securing it to the bike better.
Model: KD40S 250W 12Ah Rear Motor with Torque Sensor, KD40S 250W Rear Motor with Torque Sensor
Size: 700C (28"), 28 inch rim with tyre
Color: Black, Black
Martin Wakely
Indonesia , 3/5/2026
Very pleased so far. Easy to install and powerful
Model: KD40S 350W 12Ah Rear, KD40S Rear wheel ebike kit
Size: 700C (28"), 28 inch rim with tyre
Color: Black, Black
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