Over the last year, I would occasionally hear about these new Mobipus controllers. Once a few hot-rodders I know got their hands on one and then said they were great, I knew I had to take some time to look a little deeper at what all the fuss is about.
Most of the hot rod controllers that are found on powerful ebikes are actually designed for small motorcycles, so this is just another variation of that theme (the pic on the header above is Sketch Coleman in Australia, showing off on his Mobipus-controlled electric conversion Super-moto…more on that later).
Shenta Tsai, the designer
I’ll get to the reasons that some builders like these, but first I’d like to tell a little bit about the engineer who designed them. Shenta is from Taiwan, and his family has a large business with manufacturing facilities in Thailand. Somewhere along the line, Shenta became fascinated with electric vehicles, and began hot-rodding them to learn first-hand how they could be made to run fast.
Shenta Tsai, designer of the Mobipus family of controllers
Hot-rodding a motorcycle is not cheap, but…it is MUCH cheaper than hot rodding a car. I can sympathise because I got my motorcycle license in 1978, and I have experienced first-hand how a medium-weight motorcycle can easily beat some impressive cars from stoplight to stoplight (and yes, speeding tickets are expensive). Shenta chose a common motorcycle found in Taiwan to hot rod (an E-Grom, click here), and he used it as his prototype for experimenting.
“…My bike, the Red Devil…goes from 0–100 km/h in just 3.6 seconds…” [100km/h is 62-MPH]…24S LiFePO4 (100V) 60-Ah pack, range good up to 90-km on eco, 60-km on normal. These motors are super hard to get, not from QS…I got my own magnets and send them to 9C for assembly…
...The concept of the company is built around a very simple idea and philosophy: I just want to make great products to fuel our passion, and share it with people I like. Fuck commercial products made for profit only. I ask myself, am I pleased with this; would I pay for it?…
…Never ask what your clients’ needs are because if your standards are higher, you’ve got to satisfy yourself first. My idea is simple: we don’t look for ready-made solutions, we don’t buy other people’s know-how. We go from not knowing, to knowing. I ask, am I pleased with this? That is always our starting point and ending point. Right now we are also working on developing a new BMS….”
I’ve never met Shenta, and I already like this guy.
What’s the competition for Mobipus?
If Mobipus was primarily focused on electric motorcycles and scooters (which are a very popular transportation vehicle all around the world), why are we talking about them in an electric BICYCLE web-magazine? Well, they have two models that are small enough to be considered appropriate for hot rod ebikes. And yeah…they are expensive.
A resident hot rodding guru from Canada at the endless-sphere forum is named Stephane Melancon (Doctor Bass). Recently, he has been a fan of the Adaptto controllers from Russia. I “almost” researched and wrote about them a few times, but there was always something else that was pushed to the front of the line.
In the meantime, the Adaptto company has had some issues. Every design has some pluses and minuses, and Adaptto controllers have some desirable features, but…they have also had spotty customer service, and they refuse to increase production, so they will remain hard to get for the time being. Even their fans have admitted that they are somewhat difficult to program, and programming a controller to work well with a specific motor is vital in order to get the best performance.
The other controller I have read as a competitor to Mobipus is Sabvoton, a Chinese maker of scooter controllers. In spite of a strong fan-base, Sabvoton controllers are fairly large for the same output, compared to Mobipus, and space on an ebike is a major consideration. Also, Sabvoton controllers have only one shunt, and Mobipus controllers have three…which I will explain below.
The 48070 and the 72200
The “Weichayan” 48070 (click here) is their 13S / 14S controller (13/14 cells in Series), which will run a 48V or 52V system using 35A continuous and 70A as a temporary peak. When under hard acceleration, that is 3600W of power.
The size is 120mm X 120mm, and 65mm thick (4.8 X 4.8, and 2.6 inches thick). I haven’t found anyone yet who has been using the 48070, but I think it would work well with the 1500W-rated direct-drive hubmotors with 35mm wide stators, which perform well with 3600W peak power (and they are my favorite size for a daily-commuter DD hubmotor ebike, or cargobike)
The Mobipus 48070
They also have a slightly larger 48150 model (48V 150A, click here), but I haven’t found a retailer for it yet, and they may soon be available direct from Mobipus.
The “Spiritrum” 72150 (72V 150A, click here) is roughly the same size as the 48150, and it is much more powerful. It can be programmed to run anything from 48V up to 72V (13S, 14S, 16S, 20S…which is a nominal 48V, 52V, 60V, 72V). The max volts are listed as 90V, but a 20S pack that is at a nominal (average) voltage of 3.6V per cell, is actually 4.2V per cell when fully charged, which would be (20S X 4.2V =) 84V.
The compact Mobipus 72200 with a large aluminum finned “heat sink” attached to help cooling
If you raise the voltage on your project higher (96V instead of 72V), you can get the same total power with fewer amps, which “can” allow the system to run a little cooler. However, higher volts are more dangerous to work on, plus the components for higher volts are less efficient. Lower-efficiency components will turn more of the input-watts into waste-heat instead of wheel-power. The Australian retailer I found has special-ordered the Spiritrum model as a 72200, using 72V and 200A (phase amps are limited to a max of 350A).
If you are wondering what the Red Devil uses, it is the 72600 model modded to allow 100V, which runs 100V 600A for about 60,000W (you can see a performance video of the Red Devil by clicking here). Now that very high-amp cells are readily available, many hot-rodders are experimenting with 72V systems, because the efficiency is much better, and the 20S battery packs are simpler and slightly smaller than a 24S pack.
Sketch Coleman (in the header pic above) is using the Mobipus 72600, and a video of that can be found by clicking here…
Waterproofing
One of the features of all the Mobipus controllers is the extreme water-proofing. They are fully potted, and click here for a video showing a running motor test while the controller is bathed in water. All controllers and throttles should be made like this.
A Mobipus controller test of water-proofing
Sam’s rotary throttle converter
Most electric bikes use a Hall-sensor based hand-throttle, but few high-end builders actually like the feel of the common ebike throttles. Motorcycles are a HUGE global market and competition has resulted in a wide variety of affordable mechanical cable-throttles, but if you try to use one of those, you need something to convert the cable movement into an electrical signal.
Sam is stocking the best mechanical-to-electrical throttle converter he has found. Not only does this allow the builder to use a readily-available motorcycle hand-throttle with an excellent “feel”, it also adds an extreme level of water-proofing, since the electrical portion can be tucked away inside a water-proof housing around the controller.
Sam’s motorcycle throttle to electrical converter
The Dashboard
One of the really great things about the Mobipus system is the dashboard. Instead of designing a proprietary display that you can only buy from Mobipus, the system is designed to accept any windows device as a display. This means your display can be a s small as a smart-phone, or as large as any readily available windows tablet device. Since you wouldn’t be using the display for its computing power, you can even buy a used one to save quite a bit on the price.
The Mobipus display
More Features
The Mobipus uses true sine-wave control for a motor operation that is as smooth and quiet as is possible.
It has an adjustable regenerative braking feature (called regen), which converts a motor into a magnetic brake while slowing down. Many people seem to be excited about how a few watts are pumped back into the battery by regen, but the amount is very small. Using regen as a brake is a feature that I am finding is extremely popular once anyone tries it.
It also uses what’s called Field Oriented Control (FOC), which requires the controller to measure the current in each of the three motor phase cables. This is why it has three shunts instead of only one. A shunt is a conductor that has a very precisely-measured amount of resistance, so the controller can measure how much current is passing through that particular cable by calculating the very minor voltage drop across its length during operation.
Ballarat Ebikes in Australia
Sam Dekok runs Ballarat Electric Bikes, which is close to Melbourne in Australia. So far, he is the only dealer I’ve found for Mobipus controllers. English is his native language, and if you don’t want to program your Mobipus controller, Sam learned everything about the Mobipus programming, so he can program it for you.
He can even change the program after you have it, by remotely accessing it if you hook it up to your internet-enabled laptop (for a fee). Be aware that one of the things that customers have really liked is how easy and intuitive the programming. Shenta hated how hard all of those other controllers were to program, when he was experimenting with all of the other options.
Sam has been a hot-rod ebike enthusiast for many years, and his day-job is building hybrid vehicles for the Australian government. His youtube channel has one video that is comparing the Mobipus 72200 and the 72600 (click here), and his other videos are in an index, found here.
Sam currently stocks the 72200, and also the 72600, which he feels will be the most popular. The 600A version is roughly twice as large as the 200A, and that one is really only suitable for an electric motorcycle.
Ohbse in New Zealand
The endless-sphere forum has a member from New Zealand, who calls himself Ohbse. Here is what he has posted about his Mobius build.
“…When compared to the common Sabvoton 72V 150A controller it’s very favorable, less than half the volume, less weight, more power, much better software, better support, more safety and features. Superior connectors, better build quality and comparable price, though much cheaper than the Adaptto or Kelly options.
I’m now running a 72200 on my DH Comp with a QS 205 50 V3 3.5T in a set of 17″ wheels with Heidenau K56 tires, 20S / 12P of Samsung 30Q cells for about 2.5-kWh. Currently configured to about 300A phase/180A battery and it really hauls ass, while being exceptionally controllable…”
A Mobipus-controlled ebike from New Zealand
Jim McPherson’s off-roader
I’ve reached out to Jim McPherson, who has posted a video of his high-powered Mobius-controlled off-road ebike on youtube. I am hopeful he will respond, so I can find out more information about it.
Mobipus has posted on endless-sphere, and that discussion thread can be found by clicking here.
The link they provided indicated you can info direct from the customer service by emailing Danny@Mobipus.com
Written by Ron/spinningmagnets, November 2018