How you plan to use your e-bike may leave you little choice on the class you select. For example, I live near the Torrey C. Brown Rail Trail where I put as many miles riding on the trail as I do on the road. Since the only class allowed on the trail is a Class 1, my only choice in is a class 1 if I want to continue using the trail.
On the other hand, if I used my e-bike as a commuter where assistance up 28 mph would help me ride safely in traffic, and I wasn’t concerned with traveling longest distances on a single charge, a class 3 bike might be my only choice.
Finally, if you want a bike that doesn’t need to be pedalled, a Class 2 bike is the only one that would fill the bill.
Initially, when I was shopping for my e-bike I thought that the most important factor to increase my range would be the size of my battery. So I wanted the biggest battery I could find, in my case 840 watt hours. It only made sense to me that the bigger the battery the farther it would take me.
While it’s true that a higher capacity battery would take you farther if everything else remains constant, the vast majority of a battery’s power is used to move the air around you unless you’re climbing a steep hill. To make matters worse, as speed increases the power needed to overcome air resistance increases with the square of the velocity
Since the power needed to increase speed is not linear,
For example, based on data from Cycling Power (road-bike.co.uk) and other sources, it takes about 120 watts to ride at 15.6 mph. However, it would take about twice the power (250 watts) to increase the speed to 20 mph and more than six times the power (about 750 watts) to reach 28 mph.
In terms of range,
Increasing speed from 15.6 mph to 20 mph will reduce range by about 50%.
Increasing speed from 15.6 mph to 28 mph will reduce range by a staggering 85%.
Before choosing what e-bike class is right for you, consider if speed or range is the most important factor to you. You can’t have both. If range is the most important factor, I would opt for a class 1 over a class 3. This will optimize your range and reduce the temptation to be seduced by speed. If speed is your biggest concern a class 3 is the only bike that will provide assistance beyond 20 mph.
In the world of cycling, faster is better! Right? So when I started shopping for an electric bike, I instinctively focused on the fastest e-bikes I could find. That mindset immediately narrowed my search to class 3 e-bikes. Class 3 bikes are the only class that provides assistance up to 28mph. Class 1 and 2 bikes only provide assistance up to 20 mph.
I never really considered how often I actually ride at 28 mph. In reality, unassisted I generally only reach 28 mph on the downhills. Even then, that’s about the speed I start thinking about gently applying my brakes to safely maintain control of my bike so I can maneuver around obstacles I might encounter on the roadway. I know I’m not alone here. After checking Strava, I found the median cycling speed is somewhere around 15 mph.
In addition to not feeling natural riding at higher speeds than I normally ride, there was another unexpected consequence I hadn’t considered.
While I’ll admit it was a thrill to pick up my speed to 28 mph on a safe straight section of road, I feel that the class 1 bike rides at speeds closer to the speed I feel most comfortable riding and that drivers can more accurately judge my speed to safely interact with me on the road. So when choosing the e-bike class that is right for you, consider how fast you ride now and if you would feel safe riding significantly faster.
Choosing the e-bike class that is right for you is a huge consideration when purchasing a bike. That said, while U.S. bike manufacturers and suppliers have agreed on the three e-bike classes below, not all states have. So, before buying a bike check your state’s laws and regulations first. A good place to start would be with MOVING E-BIKE LAWS INTO THE FUTURE.
THREE E-BIKE CLASSES:
CLASS 1: Bicycle equipped with a motor that provides assistance only when the rider is pedaling, andstops assistance at 20mph. CLASS 2: Bicycle equipped with a throttle operated motor and stops assistance at 20mph. CLASS 3: Bicycle equipped with a motor that provides assistance only when the rider is pedaling, and stops assistance at 28mph.
In my case I ride on both roads and trails. While a class 3 might be a good choice for the road, most of the trails I ride only allow class 1 bikes. So if I want a bike that will do it all, a class 1 bike is the only choice for me. On the other hand, if I want to use my e-bike for commuting and not on trails, a class 3 bike might be the better choice.
With the start of the new year generally come new resolutions to get more exercise and to lose some weight. But, can you do that on an e-bike? If you are more active with an e-bike than without, you should see some benefit. However, the question in my mind is it a worthwhile workout? Unfortunately, that answer isn’t as clear because an e-bike can offer such a wide range of assistance. For example, at level 1 on my e-bike I’m doing most of the work and the motor providing about the same assistance as a good tailwind. However, at level 9 it is like riding an electric motorcycle with the motor doing most of the work.
Perhaps the best tip I can offer for maintaining or improving fitness with an e-bike is to use a heart rate monitor. Without a heart rate monitor it is very difficult to judge the intensity of the workout. Using a heart rate monitor I found that I was getting a lot of aerobic exercise on my e-bike. In fact, I was getting more aerobic exercise simply because I enjoyed the e-bike so much that I was riding my bike more.
On the other hand, I also found that I wasn’t getting any anaerobic exercise on the e-bike because I was dialing up the assistance and zipping up the hills without putting in much effort. To get a meaningful workout I have to calculate the heart rate and my intervals I want to maintain and adjust my e-bike assistance to get the workout I want.
One of the BIG advantages of the Bafang Conversion Kit is that it is configurable by the user, unlike my Bosch powered e-bike that can only be configured by an authorized dealer. As I’ve mentioned earlier, my current Bafang configuration is not compliant with the U.S. bike manufacturers’ and suppliers’ three e-bike classes. That said, I can easily reconfigure my bike to be completely compliant with a class 1, 2, or 3 bike.
For example, I live near the Torrey C. Brown Rail Trail that only allows Class 1 e-bikes on the trail. No problem, I can unplug and / or remove my throttle from my bike and limit the speed to 20 mph in the controller and I have a class 1 bike.
Similarly, I also ride my bike on the road in traffic where I sometimes feel much safer riding at the 28 mph limit for e-bikes . Again, with the throttle unplugged and / or removed, I can set the maximum speed in the controller to 28 mph and I have a class 3 bike.
Finally, if I want a Class 2 bike I can install the throttle, limit the speed to 20 mph in the controller and use only the throttle without pedaling and I would have a class 2 bike.
In my opinion, this is a big thumbs up for Bafang and a big thumbs down for manufacturers like Bosch. Manufacturers should not treat e-bike riders like children. Users should be free to configure their bikes to fit their needs and within the laws and regulations of the areas they ride. Otherwise, people will only find ways around needless restrictions with products like SPEEDBOX 3.0 for Bosch e-bikes or buy e-bikes from manufacturers that don’t impose unnecessary restrictions.
I want to tour with my e-bike so the range the battery will provide is a very important factor for me. Unfortunately, e-bike batteries can be the most confusing component of the bike. For example, my battery is a 48 Volt, 840Watt Hour, 17.5 Amp Hour battery. But what does that mean? While Bafang USA Direct states that it provides, “Up to 840-watt hours for an incredibly long range,” that really isn’t much help.
E-bike manufacturers tend to focus on watt hours. However, range cannot be determined by simply dividing a battery’s watt hours by the watts of the motor. Range will vary widely based on many factors including type of bicycle, rider posture, total weight, tires, riding speed, pedal assist level, terrain, riding surface, prevailing winds etc. So while my battery might provide power for an hour running full blast on throttle, it may also provide assistance for 100 miles or more on assist level 1. Only experience will tell the true range of my bike and battery.
However, I have found a very useful tool for estimating the range of a motor and battery combination. While the site is Bosch specific, it can provide an idea of what range a motor and battery can provide under various conditions. Check it out at https://www.bosch-ebike.com/us/service/range-assistant/ or click here.
As I posted earlier, I had to mount the battery on the rear rack because if I mounted it on the down tube I would have to give up both water bottle cages on my frame. Since I couldn’t find an e-bike specific battery rack that would fit my battery, I need to fabricate my own. The battery is the most expensive component of my conversion kit. So, I wanted it to be super securely mounted on my rear rack.
Initially, I bought the Wolf Tooth B-RAD 4 Mounting Base for this purpose. The B-RAD 4 is Wolf Tooth’s longest base with 9 threaded holes for ultimate flexibility. While my original idea of using the B-RAD 4 on the rear rack worked well, I realized that the B-RAD Base would also give me the ability to precisely position the battery on the downtube.
Now, with the B-RAD 4 I’m able to move the battery to the downtube and still save the seat tube bottle cage. In addition, my rather large 840WH battery is safely tucked inside the bicycle frame and approximately 9 lbs. of weigh was moved lower and more centered on the bike for improved handling.
For enhanced safety I ride with my bike lights lit day and night. I notice that drivers are more likely to notice me and the speed that I’m traveling when I’m using lights. So I was delighted that Bafang integrated a 6 volt DC connection for lights on their motor – and that the lights can be turned on and off through the Bafang control display.
On the downside, the bafangusadirect website only offers a headlight and no taillight. Consequently, I had to find my lights elsewhere. This seems a bit short sighted of Bafang to ignore the road bike market needs by not offering a taillight. Hopefully Bafang will consider a taillight in future offerings.
A word of caution when considering e-bike lights. E-bike lights and dynamo lights are not the same. Unfortunately, I couldn’t find e-bike lights with a flashing option. I think that flashing lights are better for getting a driver’s attention during the day. If you know of any e-bike flashing lights, please let me know by leaving a comment below.
Another Bafang design flaw is the motor has a tendency to come loose. I experienced this problem several times within the first few hundred miles of riding. Bafang must be aware of the problem. A google search on “bafang motor coming loose” will illustrate examples of the problem and offer many solutions.
Caution fixing the problem. Initially, I simply tightened the fixing plate bolts to remedy the problem. Unfortunately, I didn’t use a torque wrench and the bolts have a specified torque of 10 newton meters. I over tightened the bolts and stripped the threads in the aluminum alloy motor casing. Needless to say now my repair became a much bigger job because I had to install a Helicoil in the motor casing to repair the damaged threads.
The best solution I found to fix the loose motor problem was to install a BSBF-1 Stabilizer Bar as an alternative to the Bafang fixing plate. The 3rd party Stabilizer Bar attaches to the chain stay of the bike with a hose clamp holding the motor solidly in place. However, I did rotate the stabilizer bar and clamped it to the seat tube to position the motor higher. For an nice clean installation, an M6 Rivnut and bolt can be used in place of the hose clamp.
Come on Bafang! If you see third parties fixing your design flaws to make your product workable, why not strive to make an outstanding product and fix the problem yourself?