Controllers for brushless motors: E-bikes require high initial torque and therefore models that use brushless motors typically have Hall sensor commutation for speed and angle measurement. An electronic controller provides assistance as a function of the sensor inputs, the vehicle speed and the required force. The controllers generally allow input by means of potentiometer or Hall Effect twist grip (or thumb-operated lever throttle), closed-loop speed control for precise speed regulation, protection logic for over-voltage, over-current and thermal protection. Bikes with a pedal assist function typically have a disc on the crank shaft featuring a ring of magnets coupled with a Hall sensor giving rise to a series of pulses, the frequency of which is proportional to pedaling speed. The controller uses pulse width modulation to regulate the power to the motor. Sometimes support is provided for regenerative braking but infrequent braking and the low mass of bicycles limits recovered energy. An implementation is described in an application note for a 200 W, 24 V Brushless DC (BLDC) motor.
One of the primary purposes of an e-bike is transferring power from the motor to the drivetrain to "support" your regular pedal stroke. All of the different motors do this in relatively the same way, although subtle differences in their power output make them all feel slightly different. It is important to note that all of these systems work impressively well, the differences between them are relatively subtle but noticeable. We tested this metric primarily based on feel, as opposed to any sort of scientific measurement, and our testers could all notice the differences between the various models. All of the e-bikes we tested have several support modes offering varying levels of pedal assist support. The Commencal and Specialized models both offer three, the Trek has four, and the HaiBike has five levels of pedal assist support. All four models also have a walk-assist setting which provides up to 3.7 mph of support in the event you have to hike-a-bike to help you push these heavy bikes uphill.
Mountain bikers and their associations (which I used to be a proud member of), should reconsider their anti-eMTB stance, realize there is a need and demand for Type 1 eMTBs, and focus their efforts on keeping trails open for all mountain bikes. Mountain bikers deserve the right to ride more of our public trails than we are currently allowed. I won’t open a can of worms with my strong opinions on where I believe mountain bikes should be allowed, but suffice it to say that we don’t have near enough access as we should.
Hikers on Mt. Tam used to say we're crazy. Roadies called it a fad. Clunkers, tension discs— we left our eyes open, heads down, and kept designing. We kept evolving, and today, the Men's Turbo Levo FSR embodies a design unimaginable 40 years ago—a trail bike with pedal-assisted power on the climbs. A trail bike that gives you the power to ride more trails.
eMTBs appeal to an extremely broad target group: some use their eMTB for daily commuting, others for after-work or weekend rides on maintained gravel roads, and others plan to do an electrified alpine traverse or even an action-packed visit to the bike park. The good news is that many eMTBs are jacks of all trades, covering a very wide range of uses. Others, unfortunately, may disappoint with poor spec or nervous handling.
E-bikes mostly use motors and battery options from a few major suppliers: Bosch, Yamaha, Shimano, and Brose. A few other brands exist, but are less reliable or powerful. Some, like the Yamaha system, have more torque and others are quieter. But generally all four make good options. Look for motor output (in watts) which will give you an idea of total power. But watt hours (Wh) is perhaps a better figure to use—it takes into account battery output and life to give a truer reflection of power.
For those who aren’t frequent riders, e-bikes open up a whole new world. While you may not be conditioned to ride 5-10 miles at a time, you can cover those distances easily with an electrical assist, which is a great way to build endurance and confidence. That same survey found that 94 percent of non-cyclists rode daily or weekly after getting an e-bike.
Range is a key consideration with e-bikes, and is affected by factors such as motor efficiency, battery capacity, efficiency of the driving electronics, aerodynamics, hills and weight of the bike and rider. Some manufacturers, such as the Canadian BionX or American Vintage Electric Bikes, have the option of using regenerative braking, the motor acts as a generator to slow the bike down prior to the brake pads engaging. This is useful for extending the range and the life of brake pads and wheel rims. There are also experiments using fuel cells. e.g. the PHB. Some experiments have also been undertaken with super capacitors to supplement or replace batteries for cars and some SUVS. E-bikes developed in Switzerland in the late 1980s for the Tour de Sol solar vehicle race came with solar charging stations but these were later fixed on roofs and connected so as to feed into the electric mains. The bicycles were then charged from the mains, as is common today. While ebike batteries were produced mainly by bigger companies in past, many small to medium companies have started using innovative new methods for creating more durable batteries. State of the art, custom built automated precision CNC spot welding machines created 18650 battery packs are commonly used among Do-it-yourself ebike makers.
I know that this topic is new and still contentious, but the community needs to be talking about it because it isn’t going away. The weather up here in Seattle is rainy and cold (no surprise there), so I haven’t ridden my new eBike except around the block to make sure it worked. I can’t wait to hit the trails (legally or illegally). Expect a follow up comparing the eMTB to my other mountain bikes both in how it performs and the feeling I get from riding it. I never thought I would be riding an eMTB, so trust me, I won’t hold back.
It was a close battle and the Specialized Turbo Levo FSR Comp 6Fattie emerged as the winner of our Editor's Choice Award. Our testers universally agreed that it was the most well-rounded performer on the trail and offered a ride that felt the "most like a mountain bike" of the models tested. It was versatile, with a lighter and more nimble feel, yet it still managed to maintain its charging chops and stability at speed. Specialized has done a wonderful job designing their Turbo Levo models with the battery and motor cleanly and stealthily integrated into the frame. The Specialized 1.3 motor also runs so quietly that you'd almost forget you were riding an e-bike if it weren't for all that power. The Turbo Levo FSR Comp 6Fattie wasn't the most powerful e-MTB we tested, but it used its power efficiently and had an impressive distance range that bested some of the competition by 15% or more in our head to head range testing.
The Liv Amiti-E+2 is a low-priced but highly versatile e-bike. It’s just as much at home on the pavement as it is on bike paths and rail trails. But don't feel constrained to groomed paths. Front suspension and 42mm-wide tires mean you can take on off-road detour on your way home from work. Speaking of work, this e-bike makes a great commuter thanks to rack and fender mounts and integrated lights for riding after dark. Internal cable routing and a nicely integrated battery make for clean lines and 9-speed shifters give you plenty of gearing options for whichever type of terrain you decide to tackle. This do-everything bike is great option if you’re riding includes a little bit of this and a little bit of that.
A low-mounted motor keeps the centre of gravity low and the entire system compact, while allowing for ultra-short chainstays and a bottom bracket that is integral to the frame. We use a high efficiency, three-phase brushless motor to provide class-leading torque and ultra quiet operation. To get instant power response on trail, we put the torque sensor between the chainring and the drive gear, and our 48v battery voltage allows for super fast charging.
Ethics aside, that’s not to say we don’t at least admire where the technology has taken us thus far – and where it appears to be heading- thanks to some of the best electric mountain bikes on the market today. Some, naturally, are more rugged and built to withstand greater beatings than others. While some feature a price tag similar to that of a new Harley-Davidson. Whatever the case, if the disposable income is there, as well as the integrity not to abuse the power these electric machines offer, then they’re certainly yours for the taking. Just have a look at our eight favorite picks below and see for yourself.
As a household name, Specialized is to be trusted in this world without a doubt. That’s because, in addition to their inventory of pedal-powered machinery, they’ve gone ahead and introduced us to their S-Works Turbo. Here, in conjunction with their custom Trail-tuned motor for off-road use, the Levo FSR frame is constructed entirely of FACT 11m carbon fiber allowing for both a lightweight and stiff ride through the local wilderness. Additional features include instant engagement, heat management, and a silent output for good measure. Not bad Specialized. Not bad at all.
Cape Fear Community College students are utilizing the E-BikeKit™ electric bike kit in the designing and building of their own electric bicycles! ORIGINAL ARTICLE POSTED by the Port City Daily staff "CFCC student-built electric bikes to be in Azalea Fest parade Some innovative designs by Cape Fear Community College students will be featured in this year’s N.C. Azalea Festival. For the past year, students in CFCC’s mechanical engineering program have been hard...
“People are buying electric bicycles as a way to reduce car trips,” Benjamin says. The data backs him up: 28 percent of survey respondents said they bought an e-bike specifically to replace driving a car. And many other reasons buyers listed for wanting an e-bike—including carrying cargo and kids, avoiding parking and traffic, and environmental concerns—also indicate a desire to get out from behind the wheel. Plus, you don’t need to change clothes or clean up when you arrive at your destination, because you don’t have to work up as much of a sweat.
This article first appeared in Electric Bike Report in June of 2013. Since then, we’ve made some changes to our motor selection - our Direct-Drive motors are now all High-Torque 6x9 wound, so they run slower (approximately 15mph at 36v or 20mph at 48v), and our Geared Motors have been replaced by a 500w version, (approximately 20mph at 36v or 28mph at 48v). The Direct-Drive is now our Heavy-Duty motor and the...
The Spectral:ON is our most challenging development project to date. With the focus on the essentials, it was our clear goal to design an E-MTB that rides like the perfect trail bike. The result is already award-winning: modern trail geometry, wheel concept with 29/27.5" wheels front and rear, plus Shimano's powerful Steps E8000 drive. With the support of the engine, Spectral:ON expands your horizons: more trails per hour, trying out new ways and pushing the boundaries. You master even steep, technical climbs playfully and enjoy the agile handling and the outstanding smoothness in fast passages downhill. Space for bottle holder, geometry adjustment and lightning-fast battery change? Standard! We've taken every detail into account to give you the ultimate E-MTB driving experience.
Torque sensors and power controls were developed in the late 1990s. For example, Takada Yutky of Japan filed a patent in 1997 for such a device. In 1992 Vector Services Limited offered and sold an e-bike dubbed Zike. The bicycle included NiCd batteries that were built into a frame member and included an 850 g permanent-magnet motor. Despite the Zike, in 1992 hardly any commercial e-bikes were available.