Davinci Drive systems start at $1400 US. This includes a motor, reduction system, throttle & controller.
A hub motor is mounted inside the rear wheel and drives the wheel directly. A mid drive like ours places the motor inside the frame and drives the rear wheel with a chain.
Hub motors place heavy weight within the rotating rear wheel. This is bad for a number of reasons. First, rotating mass should be kept to a minimum (a hub motor adds a HUGE amount of rotating mass to the rear wheel). Second, unsprung weight is a bad thing on a suspended bike. Hub motors add a lot of unsprung weight. Third, weight should always be centrally located within the chassis. A hub motor decentralizes (moves away from the center) the mass. This slows down the handling and makes the bike corner poorly. Lastly, hub motors rotate very slowly. This slow rotation decreases power per pound. A Mid Drive like ours, places the motor centrally within the frame. This reduces unsprung weight and rotating mass drastically, improves mass centralization, and allows a higher revving motor to be used. The higher a motor can spin, the more power it can make (within reason). We use small and light motors that spin very fast. These motors are very efficient, extremely powerful, and light weight. We use a belt drive reduction unit to reduce that high RPM down to a useable level. The produces very high performance in a lightweight, highly efficient package.
There are a number of answers to that question. First, most mid drive systems on the market today drive the pedal chain on the right side of the bike. This is fine for low power systems. However, it restricts power capability because the stock pedal components on the bike cannot handle much power. Also, driving the pedal chain with a motor required much deeper gear reduction as well as freewheeling cranks. This increases complexity and weight while decreasing power output. Our approach is to drive the rear wheel with a second chain on the left side of the bike. This allows use to use far fewer components, increase power substancially due to the use of components specifically designed for high output, and decreases the complexity of the system. Left side drive also leaves the pedal system completely separate from the electric drive. Separating the pedal side from the electric side gives a level of system redundancy. For instance, if the pedal chain breaks, the electric side is still complete and can get you home. Or if there was a problem with the electric system, the pedal side is completely unaffected, allowing you to pedal home.
That explains the difference between pedal drive and left side drive. Our systems are also different in other ways;
First, we use permanent magnet brushless DC motors that are extremely efficient (over 90% efficient). Most other systems use motors that are 60% to 80% efficient. All of our drive unit framework components and belt drive pulleys are CNC machined aluminum. Most mid drives are steel framework with plastic pulleys or gears. This makes our reduction system stronger, lighter, and able to dissipate heat far better than the majority of drive units on the market.
Second, we use only the highest quality components on the market and if something we require is not available, we design and manufacture it in-house. We do not settle for “What is available”. We shoot for the best!
Third, we are constantly evolving our systems. We do much product testing and evaluation both in-house and through our chain of early adopter “Field Testers” to get real world data. When we find an area of potential improvement, we implement the improvement. This is rare in the electric drive system market.
We have experience in mechanical design and manufacture in a number of industries. We have done manufacturing and consulting in propulsion, radio control, chassis and suspension design, unmanned military aircraft, and the energy market. We have been designing and manufacturing electric propulsion systems since 2003. We are a growing company that actively pursues new technology for potential implementation and we pursue relationships with like minded companies to partner with for outsource manufacturing and mutual consulting to further our designs. This is not common in this industry. Most companies are unwilling to evaluate their production and make improvements. We actually thrive on product refinement and development. We also make sure everything we make is reverse compatible with previous assemblies.
Each state and nation regulates bicycle propulsion differently. Please refer to your local laws regarding legality. We are capable of building systems to meet the street legal requirements of the majority of states and nations.
—“Can you refer me to any on-line articles regarding your systems and vehicles that use them?”
The best single source for vehicles that use our systems is the forum www.endlesssphere.com. Do a search in the electric bike section under my username “Recumpence” or “DaVinci drive” . You will find many build threads there. Also, Google Recumpence drive system, or DaVinci drive system and you will see many pictures.
We build systems to order based on each customer’s needs. Go to the contacts page and shoot us an email or call us. We will be more than happy to speak directly to you regarding your specific project needs and how to best implement a system that will accomplish the goals you have set.
It normally takes 4 to 6 weeks. It can take longer if one or more needed parts are out of stock or for custom projects. We ask for a 30 % deposit with the remainder due before system or bike is shipped.