How to Convert a Mountain Bike to an Electric Bike

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You have just bought a regular mountain bike and want to turn it into an electrifying e-bike? Well, the process is never as complicated as many would imagine. Converting a mountain bike into an electric bike requires some kits that are expressly covered in this blog as well as the necessary steps outlined below.

To convert a Mountain bike to an Electric Bike requires the following steps:

  1. Choose your mountain bike with smaller wheels and without carbon fiber
  2. Use a good electric bike conversion kits (see recommendations)
  3. Remove the brackets
  4. Install the motor unit
  5. Install the battery pack
  6. Align all the parts to function as a single unit
  7. Test the bike, and enjoy the ride
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Converting a mountain bike into an electric bike is more affordable compared to purchasing a full-blown e-bike. To add icing to the cake, the availability of conversion kits makes it more amazing and straightforward to make your speed machine within a short period. This quick read should guide you throughout the entire process.

Factors to Consider Before Converting the Mountain Bike to an E-Bike

Imagine owning a bike that can get you places within a short span with a speed of up to 40mph. If you are an avid biker, then this is the best investment you can put on your regular mountain bike and save some time and energy commuting between places.

Building your e-bike from a regular mountain bike is not only fun but also rewarding. If you don’t mind getting your hands dirty, then this is the way to go, and in the process, saving yourself a fortune. However, before diving into the conversion straight away, you should consider the following three factors:

  • The size of the motor: the best size for an electric bike and one that is commonly used is 750 watts. This size can allow your e-bike to go up to 30mph without peddling. Other bikes can extend beyond this size, though.
  • The size of the battery pack: it is recommended to go for a battery pack that suits your intended use and preferences. In case you plan to travel long distances, then you should invest in a larger battery pack. The same applies if you do not want to charge the battery now and then.
  • The type of the charger: some conversion kits come with a charger. However, if you are in a position to get one, it is advisable to go a lithium-ion pack due to durability. The package might come at a high price, but it is worth the investment.

The steps how to convert a regular mountain bike to an electric bike are:

1. Choose Your Bike

This step applies to all bikes, that’s mountain bikes and ordinary alike. Whether you are buying a new one or using an old bike. Consider the following factors when picking the right bike to be converted:

  • Ensure the bike has no carbon fibers: the material used to make the bike matters because of the incoming weight (from added electric components). Carbon fiber is susceptible to load and may collapse when you add the conversion components.
  • Go for smaller wheels: be sure to use a wheel size of about 26 inches or slightly larger.
  • Get a bike with a bottom bracket and a stiffer frame: the entire construction process requires these two components. Some bikes do not come with them.
  • Ensure the bike has wider handlebars: you will need to attach extra accessories to the bike to make it electric. These new equipment require enough space to fit in.
  • Go for the disc brakes: for the best experience in maneuvering steep landscapes, you require a bike with front disc brakes.

If you already have a bike, then you can go ahead and try to fix it in line with these factors. Some conversion kits are only adaptable to specific structures that might not be a match for your bike.   

2. Pick The Right Bike Converter Kit

The next step involves purchasing an electric conversion kit. The kit offers the best and easiest way to convert to an e-bike. The conversion gears are even more optimal. Accordingly, they come with bolt-on equipment that includes throttle, hub motors, and speed controller. Alternatively, you can get the pieces separately, but I strongly recommend going for a full pack.

In case you go for the second option, ensure that you also buy brake levers, gauges, and displays. But, they might be optional, depending on your intended outlook and preferences.

For the right conversion kits, you need to take a look at these simple but essential factors:

  • The price of the package: as much as you would like to cut out as much cost as possible, you are also advised to avoid buying cheap items. In most cases, you will get what you pay for. Going for the most low-cost kit around might damage an already quality bike.
  • The size of the conversion kit: the size of the wheel and the equipment should always match. The same applies to the weight of the kit. In case you buy a package that does not match the size of your wheels, consider reversing the wheels of the bike. The processes of changing the wheels would align the gear’s positioning when attaching the hub motor to the front wheel.
  • The type of the conversion kit: ensure that you are purchasing from a reputable dealer to enhance the quality of the e-bike. Every aspect of the bike is very subjective and requires personal research to match your needs. The best brands are ones that accept cash back in case the kit does not fit.

All factors considered, you should also ask your retailer about the composition of the kit as many do not come with batteries.

3. Remove the Brackets from your Mountain Bike

This is the step where you start the building process since you already have all the equipment in place. It is as simple as changing a tire as long as you have matching parts. All that is required is removing the brackets from your bike to start deconstructing it to an electric one. Follow the steps to remove the brackets successfully:

  1. Upsidedown: Flip the bike to make it stand upside down with the support of its seat on the ground.
  2. Lever: Open the security around the lever of the bike through the quick-release gear.
  3. Remove the wheel that you want to change (either front or rear). It is advisable to use the rear wheel to hold the battery, but you can do that on either wheel. If the mountain bike you are using has a cantilever brake attached to it, then you will have to open it. If your model does not have it, then you can just use the rim.
  4. Remove the pads: Use the needle-nose pliers to remove the pads that hit where the bike’s brakes touch.
  5. Pull the derailer back: If you are working on the rear wheel, you will need to hold the frame. Alternatively, you can get a second hand from a friend. Delicately pull the derailer backward until you hear a click.
  6. Remove any other attachment to the wheel, such as the chain.

With that done, skip to the next step, which involves mounting motor to the bike

4. Install the Motor Unit to the Bike

At this stage, you need to use the tire and tube in the conversion kit in place of the one you have removed. It is the reverse of the third step. Instead of removing the wheel, you will be putting it back. The difference is that this time the wheel has a motor attached to it. The only struggle you might face is putting the chain back on the bike.

Replace the new tire properly then close all the levers you might have opened. Use a pin or clip to secure your pads in position.

Use calipers to tighten the brakes and align them accordingly, especially if they feel a bit off. In case of hydraulic brakes, ensure you pump the levers. If you have mechanical brakes tightening them consequently is enough calibration.

The process should be straightforward with the conversion kit at hand. Every pack comes with steps and instructions to be followed. Also, the pictorial representations and specs are accompanied with the tips on use. Follow the steps outlined on how to install the parts to a T, and you will find it an easy task.

Giving you direct advice on this might not make a lot of sense since the installation process is affected by several factors. The size of your wheels, voltage, and brand of the product you are using, and your intentions determine how you go about this phase. Once you are done, connect the gauges and the handlebar.

5. Install the Battery Pack

Use the directions given in the conversion kit to go about this phase. Majorly, you will have to plug the battery to the connectors that are already attached to the wheels.

The connectors attached to the speed gauge will basically connect directly to the battery. The two will then align and connect to the throttle. Consider using a pair of pliers or any other tool.

Red alert! Avoid attaching wires that do not mix. Otherwise, you would risk an electric spark that might be a threat to life. If you are frightened, you can use the help of a professional. But nothing should be scary as all the steps are expressly outlined in the conversion kit.

It is essential to have the battery protected from wear and tear, rain, or any other form of water by the use of a battery box. You will have to drill some holes in the box and connect it to the battery. Alternatively, you can use foam to cover the battery as a protective layer. It’s advisable to use a light box to save energy used in propelling extra weight forward.

Always ensure that you drill the holes on the box before inserting the battery pack to avoid damaging the controller. When all is done, you should note that the box and the battery are placed in the region you usually have your water bottle. The location lowers gravity for the stability of the bike, keeps the aerodynamics in place, and allows you to peddle easily with no disruptions.

Note: Every battery pack comes with different instructions.

6. Connect All the Parts as a Single Unit

This phase is probably the easiest. It involves securing all the cables and connecting them to the throttle and the battery. Link the wires together from the wheels to the battery pack and the handlebars. The start and stop functions are attached to the handlebar to make it easier for you.

To simplify the entire process, you should follow the following tips:

  • Mark everything you deconstruct. If possible label the parts or take a picture, you can refer to. Alternatively, you can memorize how the pieces were connected to avoid fitting parts in their wrong place once you start to reconstruct the bike.
  • Strengthen the hold around your bars using zip-ties. This process helps to solidify your construction to ensure that all parts are kept robust in their places. The parts should not be loose or tumble around the wheels. As a precaution, always wear a helmet when riding your bike.
  • Use soapy water: In case of trouble with the handlebar in this step, you can use foam or soapy water to pry the grips open. Alternatively, you can use oil and a screwdriver as you wiggle the clamps off. Pliers may come in handy in this step.
  • Do not over-tighten the wires connected to the handlebars. Allow some space to aid your turning when riding your bike. In the same line, do not leave too much slack as the wires might get caught against the wheel. Use zip-ties to attach these wires.
  • Connect the battery: Now come to the tricky part, which involves connecting the battery. In case it does not match the other parts of your bike, you will need to alter the wire connector linking every part. Soldering iron or electrical connectors should aid your process. On the other side, you can use connected wires.

If you follow all the tips carefully, you will have got yourself an electric bike in the end.

7. Test and Ride!

Without any other further ado, it is your time to test your new Electric Mountain Bike and hit the road. The new bike comes with more speed. Be cautious to avoid flying off the bike, especially if it is your first trial. Start by doing considerable speed and avoid steep or rugged terrain until you are sure you have the necessary skill to wade through. However, if you an experienced biker, then you can hit top speed right away.

The Best Electric Bike Conversion Kits

Here I have covered the three best electric conversation kits of 2020. You are not limited to these and may go any other brand that suits your needs.

1. Bafang 8Fun (mid-drive kit)

This kit comes with a battery and a motor size of 750W. It is currently the best e-bike conversion kit in the market for those that can afford it. Bafang 8Fun is recommended for people that do not like the rear wheel kit. The motor in this kit is placed in the middle part of the bike; hence it is a mid-drive kit. Thus, the engine positioning does not affect the performance of the electric bike but is instead a matter of preference. 

– Features of the kit

  1. The Bafang 8Fun is built with a mid-drive that is waterproof. This aspect of the machine ensures efficacy in performance regardless of the weather condition.
  2. The crank motor operates on 850W and 48W, being a mid-drive kit.
  3. The battery is made of lithium to ensure comfortable cycling with little paddling.
  4. The motor has a 120-rpm rating, which enhances the performance of the bike in the long run.

Among the other kits, this one has the quietest motor that makes it easy to monitor its performance and condition as you ride along. In this manner, you can take the necessary actions and precautions whenever the need arises.

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The kit also includes a tracking device that ensures the safety of the bike in cases of theft. The online tracking system is in-built by the manufacturer and helps in monitoring the location of the bike at all times.

The parts also come with elegant designs and amazing features. They are equally light to cut the extra weight on the e-bike.

2. AW 48V (rear-wheel kit)

This pack does not include a battery. However, the motor size is 1000W. It is the most affordable for lovers of the rear wheel electric kit.

– Features of the kit

  1. The kit operates on a 48V and 1000W motor. The power is enough to steer the bike through miles.
  2. The motor is rated 470 rpm, making it sufficient to generate power in the shortest possible time. The efficacy of the engine is 80%.
  3.  When fully fixed, the bike can go up to 48kmph, which enough to cover long distances.
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The best thing about a rear-wheel electric bike is that it does not have moving parts hence no friction. Therefore, you do not need to keep oiling the parts time and again. The motor controller also comes in dual mode for effectiveness. The mod creates a hall and no hall effect that aids in enhancing the durability of the bike over time.

3. JaxPety 36V (front-wheel kit)

The kit does not include a battery, while the motor capacity is 500W. The front-wheel kits provide more flexibility to the electric bike. You will need to replace the front wheel of your regular mountain bike with a JaxPety front wheel to make it useful. But if your old wheel can support the system, then there is no need to get a new one, as long as you are safe and comfortable.

– Features of the kit

  1. This kit is the simplest and most straightforward to use and would take less than an hour, converting the bike.
  2. It has a 36V 500W rated motor. Some motors are rated as high as 1000W but require down rating to 750W to meet the legal threshold for road use in the USA and other countries. Such power is enough for uphill cycling with a lot of ease.
  3.  The kit also includes a brushless hub that is essential in reducing friction and irritating noise when riding.
  4. For the package that comes with a battery, it will be an 11.4 Ah lithium battery. This type is well above the standard 10Ah found in most kits for added power when required. The lithium component is suitable for efficacy and weight. Additionally, the package comes with a free battery bag for more effortless mobility between the charger and the electric bike.

This kit quickly eliminates the drive system with chains and gears. The simple mechanism makes the package lighter on the bike and reduces friction for better performance. The rotation of the motor is also rated at 470 rpm, making it hit 28mph, which is a good speed considering the 80% efficiency.

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The one year warranty, money-back guarantee, and free replacements on the product are sureties of its efficacy alongside the dual-mode controller. The only worry with this kit is the powerful 1000W type that has a weird feeling when hitting top speed. You will feel like being dragged along, so if you are a beginner, it is recommended to use such power on the rear wheel. The same might also be an excellent feeling to experts that are used to applying the full torque.

Factors that make this kit interesting are the extra features and items that come along with the full package. You will get a front wheel, harness, disc holes, elastic ropes, and grips for the handlebar, brake lever, and controller.

Choosing the ideal battery for the electric bike

To get the right battery for the kit (in cases of packages that do not come with a battery), you will have to some research. Get the cell that is compatible with the parts that you have. You can consider going for ones between 36V and 48V with a capacity of 10Ah to 20Ah. Anything in between that range suits the standard measurement for a particular function electric bike. Going for anything below those units limits the performance. At the same time, anything above that range could cause damage to the system. 

 The intention should be purchasing a battery that aligns well with the intended use. It is equally essential to charge the battery first before installing it into the system. Charging the battery occasionally amounts to the price you will have to pay when converting your mountain bike to an electric bike. The speed and power of the bike depends on the voltage you opt for.

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The Ah rating on the battery indicates the period taken for the charge to be ultimately used up. For instance, if you do not ride for more extended periods, you can go for the 10Ah battery. The 20Ah battery is suitable for longer distances before dying out. Therefore, the type of battery you go for should be influenced by your use of the electric bike. It is also crucial to confirm if the voltage is in synch with the kit system that you are installing on your bike.

Tip: Ensure that you purchase the conversion kit and the battery from one dealer, if possible. The reason being, such combination is easier to install and also offers an easy way of consolidating return when there is a problem with the system.

Do not get yourself on the wrong side of the law

There is no denying that you will be raring to hit more speed with your new bike. It is, however, crucial to take note that there are debates about the laws on these types of bikes. Some states in the USA have not settled on whether treating them as bikes or cars.

The federal law allows a speed of up to 20mph, whereas other regulations follow the bike laws. You can reference the electrical bike law for the state you are in to ensure that you are not caught on the wrong side.

Extra tip: make sure your battery is charged to a region between 80% and 90%. Having a full charge (100%) may shorten the overall life span of the cell.

Final thoughts

You have successfully converted your mountain bike to an electric bike. All the work and fun deserve a pat on the back and are proof that you enjoy biking as part of your life. The open road is now yours. Hit the streets and enjoy the fruits of your labor.