- Steel hardtail mountain bikes are the best bicycles for e bike conversion
- Frame and dropout strength are the most important factors to consider
- electric bike conversions may not be practical and a new e bike may be a better choice
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Considering turning a normal bike into an e bike? There are several factors to consider to ensure that you end up with an e bike that is functional and safe.
The best bikes for e bike conversion are older, steel frame hardtail mountain bikes. These bikes are straightforward and feature strong frames with sturdy dropouts, making them easier to convert, safer, and more reliable. Keep in mind, however, that it might make more sense to simply buy an e bike.
As a former elite amateur cyclist, I have a vast knowledge of all things bikes, including e bikes. I haven't done an electric bike conversion myself but I understand what it requires. This article is based on my own knowledge of e bike conversion kits and bicycles from years of experience and research.
Electric Bike Overview
E bikes, also known as electric bikes, are bicycles that are equipped with an electric motor. Some “e bikes” do have throttles and may be considered by some to be essentially mopeds. However electric bikes tend to be pedal assist bikes which means that the motor only provides electric assistance when you pedal. You can purchase a new electric bike from a bike shop or online retailer, or convert an existing pedal-powered bike into an e bike using an e bike kit.
An e bike kit typically consists of a motor, a battery pack, and a control system. The motor can be mounted on the front or rear wheel depending on whether it is a rear wheel kit or a front wheel conversion. The motor may also be mounted on the bottom bracket in the case of a mid drive system.
To convert your own bike into an electric bike, you can either do it yourself using the e bike kit, or take it to a local bike shop to have the conversion professionally installed. If you choose to do it yourself, you will need to carefully follow the instructions provided with the kit and make sure to properly secure all components. Most bikes are capable of some type of electric conversion.
Regardless of whether you choose to purchase a new electric bike or convert an existing bike, an e bike can provide a convenient and eco-friendly way to get around, especially if you live in a hilly area or want to ride longer distances without getting as tired.
Characteristics of the Best Bikes for Ebike Conversion
If I were selecting a bike for an e bike conversion, one of the first and most important characteristics that I would consider is the strength of the frame. The frame of the bike will have to support not only the increased weight of the battery pack and electric motor, but also any additional components such as a controller or display. It will also have to withstand increased forces.
It's really important that the frame of the bike is strong enough to handle the added weight and power of the e bike conversion kit. If the frame is not strong enough, it may not be able to put up with the weight of a motor and battery or the increased power and torque of an electrically assisted drivetrain, and it could potentially break or deform under the stress.
The frame of the bike needs to be able to stand up to the increased force that an electric motor is capable of creating. Depending on the specific e bike conversion kit that you install, and how hard you ride and how heavy you are, it is possible that you could subject the frame to forces and/or speeds that it was never designed to handle. That’s why I would make sure to use a bike with a strong frame if I were to do an electric bike conversion.
Ideally, one should use a steel frame for a powerful electric bike conversion. Steel is a strong and durable material that is capable of withstanding a lot of stress and strain. Most bikes with steel frames are generally heavier and stronger than aluminum bikes and have sturdier dropouts, which makes them well-suited for the job.
You can also keep an eye out for “chromoly” bikes. Chromoly is a type of low steel alloy that includes chromium and molybdenum; it is even stronger than regular steel and could be ideal for an electric power conversion. It is certainly fine to use aluminum bikes for e bike conversion, however, if you intend to use an aluminum bike, make sure that the frame is strong.
I would recommend searching the internet to see if you can find any information on the reputation of the frame you intend to use for an electric power conversion. I would never recommend using a carbon fiber bike for an electric bike conversion. They are too fragile and I would consider it dangerous to try adding weight and power to a carbon fiber bike.
The strength of the frame should outweigh any concerns about weight. Weight should not be a consideration when selecting a bike for an e bike conversion. Even if the bike is incredibly heavy, it will still be able to outperform a normal bike if it has a strong frame and is able to handle the increased power and torque of the electrically assisted drivetrain.
I have had the chance to ride quite a few electric bikes including the Specialized Turbo Levo and Turbo Vado, as well as the Cannondale Adventure Neo and the Tern GSD. All of these bikes were enormously heavy when I tried to pick them up but they outperformed regular bikes by a long shot, producing enough power that their weight became irrelevant.
Something that I noticed when riding one of these bikes, the Specialized Turbo Levo which is essentially a Stumpjumper mountain bike with electric power, is that it handled better than a normal bicycle in many situations because the heavy motor and battery pack are placed as close to the bottom bracket as possible, lowering the bike’s center of gravity and making it feel more planted. We will come back to this later on below when we discuss battery placement.
To recap, make sure that you consider frame strength first and foremost when selecting the best bikes for electric bike conversion. It is essential that you select a frame that can withstand the increased weight of the battery and electric motor, and the increased forces that the converted e bike creates when you ride it. It is also very important that the frame has robust dropouts.
The Dropouts are parts of a bicycle frame that are used to hold the wheels in place. They consist of a pair of slots on each side of the frame that the wheel axles are inserted into.
The dropouts are typically located at the end of the fork on the front of the bike, where they connect to the front axle to hold the front wheel in place, and at the rear of the bike frame where they connect to the rear axle to hold the rear wheel in place.
There are two main types of dropouts: Horizontal dropouts are found on many older bikes, and are characterized by horizontal slots that the wheel axles are inserted into from the side. Vertical dropouts, on the other hand, are more common on most modern bikes and are characterized by vertical slots that the wheel axles are inserted into from below.
In addition to their primary function of holding the front wheel and rear wheel in place and allowing them to rotate freely, dropouts also play a role in the alignment of the wheels within the frame. Properly aligned dropouts ensure that the wheels are straight and centered within the frame, which helps to improve the handling and performance of the bike.
The best bikes for electric bike conversion are those that have beefy, robust dropouts. This is because most electric bike conversions involve installing a heavy motorized front or rear wheel, which puts a lot of stress on the dropouts that they were not originally designed to handle.
The increased power and torque of the electrically assisted drivetrain combined with the increased rotating weight of the motorized front or rear wheel, can put a lot of strain on the dropouts as they try to hold everything together. If the dropouts are not robust and substantial, they may flex or deform under the force, which can lead to problems with the alignment and performance of the bike.
And while unlikely, you may push the wheels to rotating speeds they were not designed to reach, depending on the specific e bike conversion kit that you install and how you ride the bike. This could put pressure on the dropouts that they were never meant to experience.
To account for these increased forces and speeds, the dropouts on a converted electric bike need to be beefy and sturdy, with a lot of surface area for the wheel to clamp onto. They should also have a substantial amount of frame material supporting them in order to ensure that they remain structurally sound.
Like I mentioned before, when it comes to determining the best bikes for an e bike conversion, steel is generally the best material choice. Steel or chromoly dropouts are strong and able to withstand a lot of stress and strain. They are also often more substantial than aluminum dropouts, with more frame material supporting them.
Aluminum dropouts are okay, but it's important to make sure that they are robust and sturdy in order to handle the increased power and torque that the electric pedal assistance can throw at them.
Carbon fiber dropouts, on the other hand, should be avoided altogether, as they are not strong enough to safely support modifications and I would consider it dangerous to install an e bike conversion kit on a carbon bike.
Space for Battery Placement
Having room for batteries and other components such as controllers and displays is an important consideration when selecting a bike for an e bike conversion.
The battery, controller, and display are all essential components of an electric bike conversion kit, and they need to be mounted somewhere on the bike in order to function properly. Some e bike kits might come with other components such as a pedal assist sensor or a throttle.
In most cases, bikes will have enough room on the frame to accommodate the batteries and other components required. However, certain bikes with rear suspension may not have enough space within the frame to allow for the installation of a battery. This is because the rear shock and suspension mechanism can take up a lot of space within the frame, leaving little room for anything else.
If you can't find a suitable place to mount the electric bike components on the bike due to its frame shape, you won't be able to install the conversion kit. This is why it's important to carefully consider the frame shape of the bike and the kit you intend to use, and ensure that there is a clear place to mount the battery pack and other components.
Also keep in mind what I mentioned earlier about weight; the increased weight of the e bike conversion kit can be beneficial if it is placed near the bottom bracket, or as low on the bicycle frame as possible.
By placing weight on the bottom of the bike, you lower the center of gravity which can make the bike handle better and feel more planted. That is why the best bikes for e bike conversion have frames that can accommodate placement of the kit near the bottom bracket.
It’s also important to consider the brakes when determining if an existing bike is well suited for an electric bike conversion. You want to make sure that you have strong and powerful brakes that are able to stop a rapidly spinning wheel that is potentially going faster than normal, and may be heavier due to the presence of an electric motor.
Disc brakes are generally the most powerful type of bicycle brakes and they are found on many modern bikes. However, you don’t necessarily need disc brakes on your bike if you want to pursue an electric bike conversion.
Rim brakes can be extremely powerful, demonstrated by the fact that high speed racing road bikes designed to go 50 mph and faster still utilize rim brakes.
In fact, rim brakes may be better for an electric bike conversion, because they are less complicated and easier to maintain. Disc brakes may also get in the way of certain e bike conversion systems, or be otherwise incompatible with them.
Unless you already have a bike that you plan to use for your e bike conversion, choosing as inexpensive a bike as possible for the conversion is important for several reasons.
Firstly, the cost of the electric bike conversion kit can be significant, ranging from around $300 to $1000. If you add this to the cost of a bike, you may end up paying a similar price to what a brand new purpose built e bike costs, which might make the conversion no longer worth it.
Another reason why a low cost bike could be beneficial for an e bike conversion is that it can allow you to allocate more of your budget to the e bike conversion kit. The higher quality kits can be expensive, but they are important for the overall performance and reliability of your e bike.
By choosing a cheaper bike, you may be able to afford a higher quality conversion, which should ultimately result in a better performing and longer lasting electric bike.
In addition, choosing a more affordable bike for your e bike conversion can also allow you to experiment and try out different e bike configurations without a significant financial investment. This can be especially useful if you are interested in e bike conversions from a hobbyist and/or engineering perspective and you enjoy tinkering, and you want to try several different configurations.
No Proprietary Parts
When selecting a bike to use for an e bike conversion, it is wise to try to use a bike with as few proprietary parts as possible. Certain proprietary parts may interfere with certain electric bike components, and they could potentially limit your options when it comes to repairing and maintaining the electric bike.
Proprietary parts are components that are specifically designed to be used with a particular brand or model of bike, and they may not be compatible with certain other brands or models. For example, a bike with a proprietary bottom bracket “standard” may require a bottom bracket that is only compatible with that brand or model, or other brands and models that follow that “standard”.
As the cycling industry has become more competitive, more and more manufacturers have introduced proprietary parts in an effort to differentiate their products and gain a competitive advantage. Often they call their new way of doing things a new “standard”, and encourage other brands to follow their lead.
Before and into the early 2000s however, most manufacturers produced bikes with similar components that were designed to be interchangeable. This allowed riders to easily mix and match components from different brands and models, and it made it easier for bike shops to repair and maintain bikes. Many of these components met ISO standards.
ISO is the International Organization for Standardization and it’s an independent association that publishes standards for a wide range of industries, including bicycles. ISO standards provide a common set of guidelines that allow bike manufacturers to produce products that will work interchangeably with products from other manufacturers.
When selecting a bike for an electric bike conversion, it is imperative that you find a bike that will work with your preferred e bike conversion kit, and this may require avoiding bikes with parts that do not meet ISO standards, particularly if you plan to use a mid drive system.
A mid drive conversion kit is routed through the bottom bracket, unlike a front wheel conversion or a rear wheel kit. A mid drive generally requires an ISO compliant square taper bottom bracket, which is extremely similar to the JIS (Japanese Industrial Standards) bottom bracket that most of these e bike conversion kits are designed for.
In general, the fewer proprietary parts an existing bike has, the simpler and easier it will be to convert it into an e bike. That's why I believe that the best bikes for e bike conversion are older, ISO compliant models with as few proprietary parts as possible.
Why Old Steel Hardtails Make The Best Bikes For Conversion
Frame Strength and Dropouts
A hardtail is a type of mountain bike that has a suspension fork to absorb shock from bumps and rough terrain, but does not have a rear suspension system. This means that the rear of the bike is rigid, hence the name "hardtail”.
A steel hardtail is a strong simple mountain bike that is well suited for an e bike conversion and will have no problem handling the increased weight of the battery pack and electric motor.
We already discussed the strength of steel and the importance of frame strength above. To reiterate, it's critical that the frame of the bike is strong enough to handle the added weight and power of the e bike conversion kit. Strong and durable steel is the most capable material when it comes to withstanding the stress and strain of the increased power and torque.
Most steel hardtails feature strong and sturdy dropouts, which are easily capable of keeping a heavy motorized wheel aligned on the bike. As I mentioned earlier, the strength of the dropouts is one of the most important factors that determines a bicycles readiness for electric bike conversion, and most steel hardtail frames are well equipped to support a pedal assist upgrade.
A hardtail mountain bike has a straight, open frame with few curves and simple angles, which makes it easy to add a battery and route wiring. Additionally, hardtail mountain bikes do not have a rear shock or suspension linkage, providing plenty of room for battery mounting.
Hardtail frame shapes are also perfect for mounting the battery as low on the bike as possible. As we talked about before, keeping the increased weight of the battery near the bottom bracket will help provide stability by lowering the bike’s center of gravity. Additionally, a hardtail frame provides a platform for endless adjustment of and experimentation with battery placement.
You can find used chromoly and steel hardtails on sites such as ebay or pinkbike for less than $500, and some are even listed for less than $250. Many of these bikes are quite old but they would make great platforms for an e bike conversion.
It is difficult to find a new steel hardtail for less than $1000. You can find new aluminum hardtails for under $500, but a used steel hardtail is probably a better bet for an electric bike conversion. Older steel hardtails generally have no proprietary parts and are strong and reliable.
Simplicity and Comfort
Old steel hardtail mountain bikes are a good choice for an e bike conversion because they are simpler and more low-maintenance than other types of bikes, such as road bikes or modern, complex mountain bikes. A hardtail from the late 90s or early 2000s usually does not have proprietary parts and meets ISO standards, which makes it easier to work on and repair if something goes wrong.
Another benefit of a steel mountain bike is that steel is a very comfortable material for bike frames. It has the ability to flex slightly, which helps to absorb shock and provide a smooth ride. In addition, mountain bike tires are wider and have knobbier treads than road bike tires, which helps to provide even more comfort by absorbing more shock and vibrations.
Mountain bike tires also provide a lot of grip and the ability to roll over obstacles, which make the bike more stable and easier to ride. The increased friction of the wide, knobby tires is counteracted by the power of the e bike motor. As you can see, an old steel hardtail mountain bike meets all of the characteristics of the best bikes for electric bike conversion listed above.
Is an E bike Conversion Worth it?
While e bike conversions can be a fun and unique project for some people, there are several reasons why they may not be worth it for many others. One of the main reasons is that there are many great electric bicycles available on the market today that can be purchased brand new for less than $1500.
Some electric bikes can even be found for less than $1000. In comparison, e bike conversion kits can cost anywhere from around $300 to over $1000, depending on the quality and features of the kit. When you add the cost of the bike itself, an e bike conversion can be just as expensive, if not more expensive, than buying a brand new e bike.
Furthermore, buying a brand new e bike has several advantages over doing an e bike conversion. For one, brand new electric bicycles are likely to be more reliable and safer than a converted bike.
This is because they are designed and built specifically to be electric bikes, with all of the components and systems integrated and tested to work together seamlessly. An e bike conversion, on the other hand, is a twisted experiment, involving taking a regular bike and retrofitting it with an electric motor and other components, which can introduce additional complexity and potential for problems.
In addition, most brand new e bikes come with a warranty that covers any defects or issues that may arise. This can give you peace of mind and save you money on repairs or replacements if something goes wrong. With an e bike conversion, you may have to rely on the warranty of the individual components, which can be more limited and may not provide the same level of protection.
Another reason why an e bike conversion may not be worth it is that it can be a lot of work to install the conversion kit. Depending on your mechanical skills and experience, it may be a challenging and time-consuming process.
Alternatively, you may have to pay a shop to do the installation for you, which can add even more to the cost of the project. In either case, the effort and expense of an electric bike conversion may not be worth it when you could just buy a brand new e bike that is ready to ride out of the box.
Finally, it's important to consider the value of your time and energy when deciding whether an e bike conversion is worth it. While some people may enjoy the process of installing a conversion kit and learning about the engineering of an electric bike, others may not have the same level of interest or enthusiasm.
If you are not particularly interested in the technical aspects of e bike conversions and just want a convenient and reliable way to get around, it may make more sense to save up your money and buy a brand new e bike instead.