In addition, Kalk weighs under 155 pounds — less than half of traditional motorbikes. Cake customized parts of the drivetrain and implemented an interior permanent magnet (IPM) motor. On a single charge, the bike travels up to 50 miles and as a bonus feature, maintenance is minimal due to the fact there are few moving parts thanks to its lack of a combustion engine.
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.
The Brose motor puts out 250 watts nominally, and can peak up to a max of 460 watts. That’s around half what the 2016 Specialized Turbo S road bike we tested last year develops, but that bike’s much-larger motor sits in the rear hub, which would massively compromise performance on a full-suspension mountain bike like this one. Spend up to the Expert or S-Works spec Turbo Levo and you get a motor that can peak up to 530 watts.
Basically, there is no reason to ride an eMTB with less than 130 mm of travel. With classic bikes, more travel usually means both less efficiency and poorer climbing characteristics, but this is not true with eMTBs – at least not up to a certain point. The best example is the Specialized Turbo Levo, which with its 135 mm of travel at the rear handles much better than most of the other, longer travel bikes in the group test. Also, eMTBs with suspension travel of 180 mm or more are often noticeably less efficient, as clearly exemplified in this test by the Haibike XDURO Nduro. It climbs a lot slower than other bikes using the same motor and the same level of assistance, an experience you will find with almost all other long-travel bikes from other manufacturers. The exception is the BULLS E-CORE EVO EN Di2: in direct comparison, it climbs a lot more efficiently, even though it also offers 180 mm of travel. The ideal compromise between uphill and downhill performance usually lies somewhere between 130 and 160 mm of travel.
As the CleanTechnica series has been showing, electric bikes are an increasingly big business, and becoming the dominant form of motorized two-wheel transportation globally. The innovation, design, and money is flowing to electric bicycles much more than motorcycles. This is part and parcel of our increasing urbanization and demographic shifts globally. Electric bikes just make sense. They shorten commutes, they flatten hills, they make groceries and children light, they are fun, and they are clean, silent, and convenient.
The BH EVO High Performance Urban electric bikes incorporate the “TS System” which fully integrates the battery in the frame and was groundbreaking when launched giving rise to a whole new style of eBikes. The Pro model electric pedal assist bikes include a compact and removable central LCD display, and a new ergonomic and highly functional remote control. See the EVO e-bikes...
In a friction drive motor, a small, solid wheel rotates against the side of the tire in order to drive it. The first motorcycles used the same concept, with a motor mounted above the front wheel. The problem is that the drive rubs at the side of the tire. It's inefficient, and it quickly wears the sidewall away. Tires need to be replaced every couple hundred miles. For this reason, you'll seldom see electric bikes with this type of drive anymore.
Fast and fun on the trail, the SDURO HardNine handles rough terrain with ease, while its large tires roll over most obstacles without missing a beat. The pedal assist makes for quick, energy-saving climbing and the bike descends surprisingly well, too. Its front suspension provides a nice level of cushion on bumpy trails and while we missed having a full-suspension on this model, that would have added additional weight and costs.
A stealthy, long travel, all-mountain electric bike with longer wheel base and adjustable seat stay hardware to optimize geometry for climbing and descending, proprietary "Active Braking Pivot" rear suspension reduces skipping, Knock Block headset and Hartzell Hug impact-absorbing downtube bumpers allow for straight downtube. Trek-invented Boost hub spacing improves spoke bracing angle and support for larger plus sized tires,…...
Up to today we have been offering up to 500W of power for those that need this extra umph depneding on rider weight or terraine but now with up to 1000W soon configurable from our hope page you will have the power you need to handle any situation. Tow loads with Stark Drive, leave the car at home and use pure electric power to bring home your groceries from your local market. Take your kids with you wherever you would like with a cargo carrier.
Controllers for brushed motors: Brushed motors are also used in e-bikes but are becoming less common due to their intrinsic lower efficiency. Controllers for brushed motors however are much simpler and cheaper due to the fact they don't require hall sensor feedback and are typically designed to be open-loop controllers. Some controllers can handle multiple voltages.
I used to mountain bike quite a lot. I was a fairly strong 17 stone (238lb) weightlifter and rode pretty fast but didn't go in for big air or jumps. Nevertheless I used to break bikes at a ridiculous rate. I broke the bottom bracket off a Marin titanium frame, I broke the bottom bracket off of a Roberts hand built mountain bike. I snapped 2 pairs of handlebars, broke cranks, pedals, chains, wheels, spokes and forks etc etc.
Because e-bikes are capable of greater speeds for longer periods of time than standard bikes, you want extra control. Wider tires provide traction and some bump absorption with little penalty. You also want strong brakes to slow you (and all that extra weight) easily. It's worth looking at the quality of the brakes and investing in bikes with better ones if you can.
It’s not as far-fetched as it sounds. In Europe, where the e-bike market has exploded, the European Cycling Union announced that it will create a new racing circuit for e-bikes, including e-road and e-mountain bikes, for the 2019 season. Following suit, the UCI said it will include an electric mountain bike competition in the 2019 World Mountain Bike Championships. Yes, there will be a rainbow jersey awarded to the world’s best off-road e-biker.
Sure, you train hard and eat right, but there’s just one thing missing—an edge. The Amira gives you two. First, there’s the performance edge you get from its FACT carbon frame and tapered head tube. The combination results in responsive handling and true get-up-and-go accelerations. Then comes the psychological edge. The feeling that, when teamed up with a lightweight, high-performance machine, there’s no limit to what you can achieve together.