
Juiced Bikes – RipCurrent vs. Rad Power Bikes
Class 3 ready (up to 28 mph with pedal assist)
Overview:
Class 3 is a new regulation adopted from Europe’s “Speed Pedelec” classification. Speed Pedelecs allow e-bikes to assist up to 45 km/h which equals exactly 28 mph.
Class 3 is the greatest gift to the e-bike community as you can get to your destination faster and more efficiently. The faster speeds also allow you to better keep up with traffic when traveling on surface roads.
As you get more fit, you will be better able to contribute to the bike’s overall speed. Class 2 bikes will cut off the pedal assist when the bike reaches 20 mph. So if you are able to pedal faster than 20 mph, you are effectively pedaling a heavy bike on your own once the bike goes beyond 20 mph.
Both the RipCurrent and Rad Power Bikes “Rad Rover” come out of the box in class 2 mode (20 mph). However, the RipCurrent is designed to be easily configured directly from the LCD display to achieve 28 mph in Class 3 mode where allowed, while the Rad Rover has no Class 3 mode.
The RipCurrent safely achieves Class 3 / 28 mph by:
- Using a more powerful 25 Amp peak controller
- Higher speed 750W motor winding
- 52 Volt battery
- Torque sensor pedal assist
- 11T/52T Cassette transmission for easier pedaling at high speeds
- Powerful hydraulic disc brakes to quickly stop from faster speeds
All of these features are missing on the Rad Rover, but are standard features on the RipCurrent (and RipCurrent S)
Torque Sensor vs. Cadence Sensor
Overview:
There are 2 types of pedal assist or PAS. Cadence-based pedal assist and torque based pedal assist. The RipCurrent uses the more advanced Torque Sensor pedal assist, while Rad Power Bike’s Rad Rover uses the Basic Cadence Assist. The difference is like night and day.
The Torque Sensor pedal assist used on the RipCurrent can sense your exact pedal force and amplify your power in real time. The harder you push on the pedals, the more assist you will get from the motor. The basic cadence pedal assists used on the Rad Rover just “turn on” the motor at a preset speed the moment you turn the pedal.
Here are the detailed differences and why you will want the Torque Sensor on your next e-bike.
Cadence Assist is the most simple type of pedal assist, as featured on the Rad Rover. This uses a magnetic disc to detect when you are pedaling and the motor turns on and when you stop pedaling the motor will turn off. This type of pedal assist is found on almost all entry-level e-bikes.
The advantage is it is an inexpensive way to gain pedal assist. The disadvantage is that the cadence sensor pedal assist turns on and off the motor like a switch and can feel unnatural and laggy. If the boost is put in the higher settings, the bike can take off suddenly when you turn the pedals.
Cadence assist-only systems are not allowed in Japan due to safety reasons. Additionally, if the boost is set lower than your desired pedal effort, it will feel like you are pedaling against the motor.
Torque Based Pedal Assist is a much more advanced technology, and is featured on the RipCurrent. There is a precision strain gauge that measures the exact amount of pressure you put on the pedals. This information is used to work out how much assist to give to the motor in real time. The measurement happens 1,000 times a second and the effect is that the pedal assist is a very smooth and natural feeling. The only way to describe it is “bionic” and the bike feels weightless. It feels totally different from the basic cadence assist which just “turns on” like a motor scooter and you are along for the ride.
To sum it up:
Once you try the Torque Sensor type Pedal assist it’s really hard to go back to Cadence-only pedal assist. Most bikes in this class, including the Rad Rover, use basic cadence sensors to reduce cost, but eventually, you will want to have the Torque Sensor pedal assist on your next e-bike if you enjoy pedaling and value a bicycle like riding experience.
The RipCurrent has both Torque Sensor and Cadence sensors with special motor control software to make the bike feel incredibly sporty and smooth.
52V vs. 48V Battery Pack
Overview:
For e-bikes with the hub motor, you want a powerful feeling to assist up hills, accelerate from stops and keep up with traffic. To get both higher power and higher speed, the most direct way is to use a higher voltage battery pack.
The RipCurrent uses a 52V battery while the Rad Rover uses a 48V battery pack. The difference can be felt right away especially at higher speeds.
With the higher voltage, the system can continue assisting you like the bike’s speed increases. Lower voltage systems feel like they are “blocking” your pedal efforts once you reach a certain speed.
A little about Voltage
E-bikes have evolved a lot since the early days. The most direct way to get more power is to increase the voltage. The early e-bikes were 24V, then later the standard moved to 36V and later to 48V but effectively got stuck there.
Voltage jumped in increments of 12V because the heavy lead-acid batteries which were used in the early days of e-bikes came in 12V format. Each time you added a pack in series, the voltage jumped by 12V.
When the industry switched over to Lithium battery packs, the lithium battery adapted to the old system. However, lithium battery packs can jump in increments of 3.6V.
To squeeze more performance out of the system without harm to the electronics, some hot-rodders added one more cell in series and the voltage is bumped up to 51.8V. For marketing purposes, the voltage is rounded up to 52V.
At the time of this writing, Juiced Bikes is the only manufacturer to adopt the 52V platform as we design our own battery packs which is very unusual in this industry.
We spent about 2 years quietly upgrading all of the system components to properly handle the increased voltage. We expect all e-bikes to be 52V in the future, however, it will take some time for this transition to happen.
Hydraulic Disc vs. Mechanical Disc Brakes
Overview:
The most overlooked component of the e-bike is the brakes. But the brakes are one of the most important parts of the bike.
The main thing to know is that there are 2 different types of e-bike brakes. Mechanical and Hydraulic. Hydraulic disc brakes used on the RipCurrent has better stopping power, better brake modulation and self adjust as the pad wears down.
Mechanical disc brakes found on the Rad Rover have less stopping power and are typically found on lower end and entry level bicycles and not appropriate for use on heavy, fast-moving e-bikes.
There is a significant difference between the feel of the mechanical and hydraulic disc. The Hydraulics slow the bike much more directly and with less lever force than the mechanical type. Once the bike pads grab the rotor, you have more fine control of the brake pressure on the hydraulic system.
Mechanical Disc Brakes:
Mechanical brakes use a cable to pull the brake pads against the rotor. The cable has some flexibility so there is a bit of spongy feel when the brake is activated.
Additionally, the cable only moves one brake pad, so when the brakes are applied, the rotor is actually bending sideways which is not optimal.
As the pad wears down, the non-moving inside pad must be constantly adjusted to achieve optimal brake performance. Mechanical brakes are usually chosen to reduce cost.
Hydraulic Disc Brakes
Hydraulic disc brakes are more modern technology derived from automotive racing. Instead of using a cable to move one brake pad, a non-compressible fluid is used to transmit the lever force to both the brake pads.
The rotor does not deflect and there is overall improved braking performance over mechanical disc brakes. The lever force is more direct you can feel the pads “punch” toward the rotors.
Because both brake pads move towards the rotor, the pads can self adjust as the pad wears down. This reduces the time wasted to continuously adjust the pads as required with mechanical disc brakes.