How we convert bikes to electric

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Who will be riding the bike we convert to electric?

When someone brings a bike to our shop for conversion we want to know as much as we can about the rider of the bike as well as the bike itself. The bike is a static, non-living, object whose value ( other than its artistic value) comes into being when it becomes one with the rider. Therefore, it is rider first and bicycle second. 

The who question is a question of responsibility. I have been ask to build electric bikes for children as young a seven. I turned down the request as the bikes we build are far to powerful for someone as young as seven.

The other day a very angry elderly man called and said, "I lost my license." "I did not do anything and they just took it away." "I want an electric bike." Fortunately, the man never arrived at the shop. We have seen those times when a person's ability to drive a motor vehicle becomes limited due to age or health and the family intervenes and takes away their driver's license. In our opinion, if a person has reached the point where they can no longer operate a motor vehicle they should not be on a electric bike. These bikes are fast and powerful and requires a certain level of mental acuity and requisite skills to manage them safely.

Age

Prior to accepting a bike for conversion we try to estimate the age of the rider as it pertains to the ability to manage an electric powered bike. Again, it is a matter of responsibility on our part to determine if a persons age will affect their ability to ride an electric powered bike. 

Age is not always a limiting factor when someone comes to our shop requesting their bike be converted to electric. We have converted bikes to electric for at least a dozen riders over 90 years of age within the last two years. Albeit, all of these riders have a long history of cycling and are very experienced cyclists. Some have cycled around the globe and across the US several times. Others are former racers. This group of elders may have many decades behind them yet they are athletes in body and soul. In addition, their collected knowledge of cycling throughout the years under diverse conditions is encyclopedic. Their bikes are always well maintained and may even be of a different era but they always make for great eBike conversions due to their fantastic condition. 

The point is, electric bikes will not pose a danger to a rider over 80 who is an experienced rider in great shape. And, as we all know, there are some who are 80 plus who are in better shape than some of us much younger.

Physical condition

We have built electric bikes for many who have recovered, or are recovering, from major life changes (for lack of a better term). Electric bikes provide the opportunity of outdoor exercise, and just to be able to get out and enjoy the day. I will not go into the long list of physical conditions that can severely impact ones mobility but I do know the following: Cycling can improve someone mood if not anything else. If someones' mood changes for the better, their outlook improves. If their outlook improves they are happier and happier people  heal quicker. One thing about electric bikes is that they make people smile. Myself, our mechanics and staff have see many times over how people smile when they return from their first ride on an electric bike. Sometimes I think we are not selling electric bikes...we are selling smiles.

A few decades back i was in a serious crash while bike racing in a criterium. As a result spent two months in a hospital. During that time, I thought of how I would give anything to be outside in the sun, on a bike, riding up a hill. A bicycle was my formula to return to health, once out of the hospital. It took a long time before I could race again but I was riding on a daily basis and that is what returned me to my heath, both mental and physical.

Experience

When a bike is brought to us for conversion we always take into account the experience of the rider. This is very important as all electric bikes are similar to low powered motorcycles. Some of the steps we take to insure the rider is going to be safe on their new electric bike is setting the power level commensurate with the skill of the rider, and making changes to the bike itself.

One of the advantages of using the Bafang mid drive motor system is it allows us to set the parameters of the motor. For example, a stock BBS02b 750 watt motor is set at 25 amps. By adjusting the amps from 25 down to 18 we have effectively limited the output of the motor to 500 watts. This does two things. First, it tones down the power of the motor and it becomes more manageable. Second, it extends the range of the battery. In fact, riders of all levels prefer to set the amps at 18 in order to increase their range. I am often ask, "At 500 watts will I lose much power?" No, hardly so much you would notice. Remember, in all of Europe the standard motor allowed by law is 250 watts so a 500 watt motor should be all one would need for most riders and riding conditions.

Considering known limitations

A man with dementia came to our shop and said he wanted us to convert his bike to electric because he kept falling off the bike every time he stopped pedaling. He thought converting it to electric would solve his problem. Of course the problem was not the bike and converting it to electric would not be the solution. 

Another day, a man and his wife came to our shop and he wanted to test one of our electric bikes. He seemed very angry. I put him on one of our bikes and stepped outside with his wife to watch him ride. He could not ride in a straight line. I looked at her and said, "Ma'am, I'm sorry but your husband should not be on any bike much less an electric bike." She agreed and said, "He had a stroke not long ago and he just wants to ride a bike again."

We do not refuse to convert bikes to electric often but when we do it is for good reason. 

Changing the bike to fit the needs of the rider

All bikes are adaptive to the rider. We can make any bike a safer bike, a more comfortable bike, a faster bike, or a slower bike. We do all of these at our shop. The most important thing we do for riders of limited ability, or experience, is to make their bike safer. We start with the tires. The tires on any bike is its foremost safety feature. Tires are as equally important as brakes. remember, a bike tire is the only contact the bike has with the surface. The entire system, including the rider, is utterly dependent on a very small section of the tire that is in contact with the riding surface. For safety's sake we try to encourage riders to increase the size of their tires to the largest their frame can accommodate. 

An added bonus of larger tires is comfort. part from suspension, tires are the number one change that adds comfor to the ride of any bike. The larger the tire, the greater the air volume (not air pressure), the better the ride. Thin high pressure tires are not needed on any bike under the power of an electric motor. 

There are many types of bikes that we convert to electric. This is not a complete list but here are some examples: Road bikes, mountain bikes, hybrid bikes, folding bikes, cargo bikes,  beach cruisers, and  vintage bikes. It is a rare day when a bike is brought to our shop and we say, "Sorry, but this bike cannot be converted to electric. 

Frame material: Frame material on a bike may be steel, aluminum, carbon fiber or titanium. The best material to work with is aluminum. The reason why aluminum  is the best material is because of the larger shaped tubes. A large flat  downtube is perfect for attaching the battery. Whereas, steel frames often have round tubes. We have come up with different methods of attaching a flat battery base plate to a round steel downtube but it is not easy. This is important as a solid connection between the battery and the frame is essential.

Carbon fiber bikes present their own challenges but we have successfully converted many carbon fiber bikes. Titanium framed bikes are similar to steel framed bikes. As such, they make fine electric bikes. Every now and then we hear of a new exotic frame material and time will tell when they come to market and when we see the first one arrive at our shop.

Everyone loves their bike. When they first purchased their bike they did so based upon their own standard of quality, comfort, style, aesthetics, budget, and personal reasons. I think all of us can remember all of the bikes we chose to purchase for our own reasons. In Addition, we can remember those bikes that were sold to us by aggressive salespeople that did not fit us, were the wrong size, wrong look, wrong cost, and under any other scenario we would have not chosen for ourself. 

The best bike to convert to electric is your favorite bike. Sometimes (more often than you would believe) a client...to be continued

An interesting thing about electric bike conversions is that a used bike works just as well as a new bike and costs significantly less. The reason for this is simple. A bicycle frame, fork, shifters and derailleurs can last for decades and the same goes for a good set of wheels. The "perishables" on a bike are relatively inexpensive. A new chain, cassette, and shifter, if needed, would cost less than a $100. If you do not have a bike to convert to electric, or the bike you have is not a good candidate for conversion, then give some thought to a used bike. Bicycle Blue Book, in San Jose California, (online at Bicyclebluebook.com) is a good source, or your local Craig's List. Remember, when it comes to converting a bike to electric think simple. The Bafang motor delivers a lot of power so a 7 - 9 speed bike is plenty of gear choices to get you up the hills.

Places to find a great used bike:

Bicycle Blue Book

The Pro's Closet

For new bikes at a great discount try:

Bikes Direct

The speed of a bike refers to the number of cogs on the cassette. A seven speed bike has seven cogs, an eight speed bikes has eight cogs, all the way up to twelve speed bikes. Back in the 70's we had a bike called a ten speed bike. Actually, it was a five speed bike with a double chainring. 

Electric bikes work fine  with as low as 6 speeds and do not need anything over 9 speeds. In fact, many times when converting a 11-12 speed bikes we have to lock out the last cogs because the chainline is so far off kilter. 

Chains for 6-8 speed bikes are very strong and come with 7.1 or 7.3mm pins. Nine speed chains are also very strong. It is when we have a 10, 11, or 12 speed chains do we start to worry. Ten speed chains are narrow, the pins are smaller, the plates are thinner and if one is not careful these narrow chains can snap under the power of an electric motor. 

If a bike is a 11 or 12 speed then we strongly recommend using an eBike rated chain. An eBike rated chain is almost twice the cost of a standard chain but a standard chain is just not strong enough to handle the torque of the Bafang mid drive motor.  

In conclusion, bikes with 7, 8 and 9 speeds is all you would ever need for an electric bike. If your bike is 9 or 10 speed it will work just fine. If your bike is 11 or 12 speed an eBike chainset is needed. 

Do road bikes make good candidates for conversions? When you look at the "Big Four" bicycle companies (Giant, Cannondale, Specialized, and Trek) you will see nearly all of the electric bikes they produce are not built on the road bike platform. The same is true for all other bicycle companies. Why would that be the case? First let's look at the negatives. Road bikes traditionally have drop bars. The purpose of drop bars is not for comfort (far be it), they are for aerodynamics. One thing you never have to worry about with electric bikes is aerodynamics. On an electric bike you can sit tall in the saddle and ride into a headwind without any effort. 

Another negative is the size of a tire that can be fitted to a road bike is between 25mm and 28mm. These are narrow tires. These narrow tires are inflated to 100-120 psi and make for a very harsh ride. Also, the narrow tires have a very small contact patch. A contact patch is the portion of a tire that is in contact with the surface at all time. The part of the tire that is on the surface is the only thing that allows us to come to a controlled stop without entering into a skid. A small contact patch will put a bike into a skid much sooner than wide tires.

The reason why road bikes use small, narrow tires is they are light and give better rolling resistance. However, electric bikes are not bothered by heavier tires or rolling resistance as it has the power to overcome what would be obstacles to human powered bikes.

We have converted many road bikes into electric  bikes and we try to fit them with the largest tires the bike will allow. Sometimes our clients will have us remove the drop bars and replace them with a flat bars. The flat bar allows for a more upright position.

We are often ask if we convert carbon fiber bikes to electric. The answer is always "depends." Many carbon fiber road bikes lay up the carbon fiber very heavy in the bottom bracket area. This is done to make for a stiff bottom bracket. The bottom bracket shell area must be stiff for the efficient transfer of power. The thickness of the carbon fiber on the bottom bracket shell will determine if a Bafang mid drive motor will fit.

In my opinion...road bikes can be converted to electric and they can be ridden safely...but they cannot take advantage of wide tires, upright riding position, and front suspension, all of which are a plus for any electric bike.

As an aside, road bikes were the only bike I would ride until I was introduced to the eBike. A electric bike meant I no longer needed drop bars (for less wind resistance) and skinny tires (for better rolling resistance) as these things no longer mattered on a powered bike. Electric bikes allowed me for the first time to ride in an upright position, on large tires with front suspension. Now when I go riding it is always on an eBike because it has made bike riding a more enjoyable form of transportation and recreation.

Do we convert adult trikes to electric? The answer to this question is yes and no. We believe the Bafang mid drive is too powerful for an adult tricycle. Instead we use a Bafang front hub motor rated at 500 watts.  One of the difficulties of all adult trikes is their tendency to tip over during cornering. If a motor is too powerful this tendency is amplified. 

In addition, there are a lot of adult trikes on the market and some of them are of very poor quality. One of the better ones is the Raleigh Tristar adult trike. The wheels on this bike are 24 inch and provides better stability. Schwinn and Workman also makes pretty decent trikes. 

Remember that trikes are large and heavy by nature so make sure you have room in your home and garage for storage. While there are a number of folding trikes on the market we find their quality is typically lacking.

We have built a number of tandem bikes and so far so good. Our biggest concern is the total weight of the riders and the bike itself. If each rider weighs 200-250 pounds, and the bike 65 pounds and the plan is to climb hills I think the motor will not be sufficient. That said, we have yet to have a single failure on any tandem we have built.

It must be remembered, all electric motors have their limit and to exceed that limit for any duration of time will literally melt the insulation of the wiring on the motor until it shorts out. 

If there is any motor capable of powering a tandem bike it is the Bafang mid drive but we must never forget that even the powerful; Bafang motor has its limits. 

We love to convert recumbent bikes and we feel the recumbent bike is the most underrated bike on the market. Our favorite is the three wheeled recumbent. These bikes are comfortable, fast, and make for great electric bikes. 

When converting these types of bikes to electric we use a special battery mount made by Terra Cycle. These mounts are specific to recumbents and are very well machined.

Working with recumbents requires experience because of the chain and the adjustable boom. All cabling has to be done in a manner that does not prevent the bike from folding or the boom from extending. However, in the end a properly built recumbent conversion is great fun to ride.

A Class I electric bike is an electric bike that does not have a throttle and the motor cuts off at 20 mph. The power of a Class I electric bike cannot exceed 750 watts. The Class I bike is allowed anywhere a standard bicycle is allowed including bike paths.

The Class I electric bike offers a lot of advantages over the Class II and III in terms of safety, greater range per battery charge, longevity of the motor, and much easier on the drive train of the bike.

A Class II electric bike is an electric bike that does have a throttle and the motor cuts off at 20 mph. The power of a Class II electric bike cannot exceed 750 watts. The Class II bike is allowed anywhere a standard bicycle is allowed except bike paths.

Disadvantages of a throttle include; Reduced range per battery charge, wears out the drive train of the bike (chain/cassette), not allowed on public bike paths or most organized rides.

A Class III electric bike is an electric bike that does not have a throttle and the motor cuts off at 28 mph. The power of a Class III electric bike cannot exceed 750 watts. The Class III bike is allowed anywhere a standard bicycle is allowed except bike paths.

This is the most popular choice as it provides the performance needed when required. On some rides you just might need that extra bit of power. In a race in Pescadero, California I was off the back of the peloton when I saw something out of the corner of my eye. From an adjacent field came a large, loping coyote  heading right for me. Well, I am still here to tell the story but I know from experience that sometimes a little bit of extra power can get you out of a tight spot.

As one can see, in the State of California it is legal to have a throttle on an electric bike but under what conditions is having throttled powered bike a good idea? For those who are not able to pedal a bike, for any reason, the throttle powered bike is a godsend. The throttle allows some to continue to enjoy riding a bike regardless of infirmity that has stopped them from riding a standard bicycle.

 We have seen far too many mechanical problems associated with throttles to give them a thumbs up for every rider. A Bafang 750w motor delivers a lot of power and that is great for climbing hills or carrying heavy loads. However, when one uses the throttle to propel the bike forward from a dead stop that same power can snap a chain or even burn up the motor. 

There is a reason why all major bicycle companies do not have throttles on their bikes and that is they can be unsafe, and can easily damage the bike. 

There are two types of throttles available for Bafang Mid drive motors. The twist throttle is of such poor quality we have never offered it as an option. The second type is the thumb throttle. There are two types of thumb throttles. The above is the heavy duty thumb throttle.

Throttles on an electric bike are dangerous as they are easily activated. The throttle is like a on/off switch. If someone touches it, or leans against it...the bike takes off with or without the rider. 

Many times we have seen people say "What's this?" as  they toggle the throttle and activate the motor. Before anyone tests one of our bikes the first thing we say is, "This is the throttle and if you touch it it will activate the motor so please be careful."

There is a difference between a bike lane and a bike path. The picture above is a bike path. A bike lane is the marked lane on a public road that is for bicycles. All electric bikes can use a bike lane but a bike path can be used by electric bike if they do not have a throttle.

Electric bikes are now being used on organized century rides and Grand Fondo's. However, most of them specifically state that electric bikes with throttles are not allowed. 

Throttles on electric bikes are probably not the best idea for all the reasons described above and should be limited to those who really need them. If properly used a throttle can be safe and even useful in certain conditions. If a throttle is improperly used a lot of things can go wrong. Therein lay the dilemma.