Hyper Fat update from Tora


We hope to have the Hyper Fat available to Canadian Customers in spring 2018.  Please stay tuned.  

*** Update*** As of April 2018 there are no HyperFat available, and my feeling is that it was a "skunkworks" project, and what came out of it is the RipCurrent S

Here is an update from Tora on the first production...

Sorry for the lack of communication recently regarding HyperFat.

It is not for a lack of working, it is for lack of time and not wanting to give inaccurate information as the situation is very dynamic. This bike has been difficult to make, particularly the controller.

Here in China the internet is a little bit different. Google, Facebook, Twitter, Youtube, IG, Snap, anything that is a blog, all of those do not exist... at all. In the best case when you type youtube.com, nothing happens. In the worse case your internet literally shuts down for like 15 min to let you ponder the "mistake you made." There are work-arounds, but they don't always work or half work.

So, basically my email box got filled up and nothing was getting in. So I upped it to the 25GB plan, but by "upgrade" apparently it proceeded to just "delete" my previous mailbox and create a bigger one from scratch. It's IMAP so this happened on all devices and computers instantly so many messages got lost as I now try to build back up the mailbox.

In the process the mail provider crippled the account because it turns out spammers open up huge mailboxes then start sending a bunch of messages from IP addresses in China, which is basically exactly what it appeared I was doing!

Some people emailed in and asked about the pre-order and I addressed them directly but not in any mass way to everyone. I will post here and then edit it in the mass email list as it seems like many people with orders or interested in the project are here.

We did not want to send out a update until we understood the situation a bit better. This bike is very high performance and quite complex to make in this Chinese manufacturing environment due to many factors, we can go into that later.

We have already flown a limited number of initial units by express (at great cost) to the Juiced head quarters in San Diego for inspection and later to the first customers with "golden tickets." Sorry some units were lost in the production and testing and we will remake those units for customers.
Initial units getting sent to the airport.
The next production that will cover all the pre-orders will start like early September. Another production with even more units has been ordered. So we can start cutting down the wait times. This process takes time and gets somewhat reset when we need to make changes.

I have been here non-stop at the factory for 2 months and my visa is up so I must depart the country. I literally cant spend any more time in China and need to reset the visa. This is already the 2nd time.

Some people noticed the price increase and we want to address that here. Basically we got rid of the lower capacity bikes and made all the bikes with torque sensors. Overall the price is around100 bucks more expensive. But we added more sizes and some other things that people who never tried the bike requested like suspension forks which is not necessarily needed.

The idea behind the lower priced bikes was to make the bikes more affordable, but do it the right way and have 100% upgradability/scalability to even the highest performance level at a later date. While in principle it made sense, what it ended up doing was guiding the wrong type of purchasing decisions and increasing SKU count for us. Most people bought the higher spec bikes anyway as most HF buyers are electric bike savvy and want the performance.

We also ended up with a higher performance than was originally specified and the smaller packs would be drained relatively fast and lead to disappointment for the entry level buyer. We could have solved the issue by making the performance lower for the smaller packs or some software hack, but screw it! We just got rid of the 13Ah packs and 750W options. There are loads of fat bikes out there with that spec and it's really easy to make these days. There is not much more to add to the conversation in that category.
Next units already getting laced up and will soon start production.
Improved software:

We adjusted the software so it can run in 0-750W or 1,000 W mode on the fly and gave it the ability to limit speed so it can be used on the road. We even added a handy Cruise Control feature which was not advertised.

These features are shipping with the new CrossCurrent S and and it would be a mess if the HF landed with less features than the CrossCurrent S. So we needed to take time to duplicate all the functions onto the HyperFat platform.

There is some myth out there that the torque sensor is harder to pedal, which is not necessarily true, so we added the ability to deactivate the torque sensor on the fly. This way even if you pretended to pedal you can still get very fast cadence-based assistance. The Cruise Control feature can lock in a base level speed and your pedal assistance on top of this will be amplified to increase the speed. This settles the argument and we can all move forward.

What is amazing about this bike is the torque sensing with such high power levels.

Cadence sensor-only hardware just kills that unless someone just really wants a cadence sensor or have limited ability to pedal and is understandable to not want to pay for something not used. So we gave the option with the software and ditched the cadence sensor hardware options to reduce complexity.

What makes the HF special on the performance side is the ability to continue the amplification effect even at the very high speeds and pedal force. Most bikes with torque sensors peak out at something around 500W-800W, so when you pedal hard, the amplification is clipped off due to the motors lack of power. If those bikes were to keep a linear amplification effect, the boost at the low pedal pressure levels would be so tiny that customers would not buy the bike.

So what most every manufacturer does is over-boost the assistance at the low pedal pressure at the expense of clipping the amplification effect when you pedal hard.

So some bikes feel jerky at low speeds and some less experienced customers equate this to being more "powerful" when doing the parking lot test ride.

The opposite happens when you pedal hard as it can feel like the bike starts working against your efforts. This happens because the controller stops increasing the power applied to the motor even when you pedal harder. Your body interprets this as feeling like the motor is working against you. Most stronger riders coming from normal bicycles will right away notice this and it's annoying.

This does not happen with the HyperFat. With the HF's higher power levels, we can set the amplification to be amazingly controllable and stable at low speeds, but when you stomp down, it really goes. What's amazing is the level of control you have even at the highest boost setting. And this continues up well past 30 mph which is way faster than most people can manually pedal a fat bike. The overall effect makes the bike feel like it weighs 10 pounds and your legs are insanely strong.

We did not need to put this capability into a fat bike, but it turns out that most fat bikes out there are kind of slow and goofy so it is a good place to start with our Hype Bikes line of high performance e-bikes.

And if we were going to go this route, might as well rip up the rule book and make a fat bike that we would ride ourselves but, rather than just make one or two of them, we designed it in a way that can be reliable, produced a scale, made affordable and serviceable. And could we just push it right off the assembly line into a box and right onto a plane to go directly to the customers doorstep? And why stop at one model, why not make more form factors?
Initial bikes getting programmed before getting boxed to come to San Diego.
Motor challenges:

It turns out to be very difficult. First off most fat bikes just use the Bafang and similar 500-750W hub motors which are mass produced these days. We tried all of them and the performance just cannot be called "Hyper" anything.

The other way is to go with a mid drive, but the available strap on 1,000W mid drives out there are not torque sensing. They are also somewhat clunky requiring many gear changes as you move faster or need more torque.

Now some 1,000W mid drives with torque sensors are slowly coming to the market. But they still suffer from the need for constant gear changes for electric motors which technically don't really need to change gears.

Only the human needs to change gears as humans have insanely narrow power bands relative to electric motors. But since the human and motor's power are forced through the same transmission. The electric drive system is compromised and this becomes apparent when you try the really high powered mid drives. But it does work well for lower powered system.

Also you really need exotic derailleurs to cope with the power being sent through the transmission. Mid-drives are already technically more complex and as a result more expense piled on more expense.

So we went with MAC Motor at the moment they completed the Fat spec motor. They usually make very high powered motors for DIY bikes with the "need for speed." This 1,000W motor is incredible, but has never been integrated into a torque sensing production e-bike. It also has some quirky features that makes it difficult to integrate. Like the strange position of the hall sensors and lack of a speed sensor. The motor is relatively light and I guess there are some compromises due to weight and the need to fit the motor into standard 135mm rear dropouts.

Our controller supplier is quite good. They make all of Bafang's mid-drive controllers from the smallest to the largest. The have become masters at translating how you want the torque sensor to feel into code that's programmed onto the controller.

They tried in the past to tune the MAC motor and just gave up. We begged them to try again and it took many months and many failed or half working systems before we got the thing to work. We had to bring these two very different suppliers together to focus on jumping this hurdle.

Sometimes the MAC engineers went to the controller supplier to help work out issues. Many times we went there and spent days at a time at great annoyance to everyone considering the relatively tiny number of units of this project.

We also had to make our own wire harness because the motors wires are so big. Also the lack of speed sensor means we had to make provisions for an external speed sensor which is kind of clumsy since like every other hub motor has a speed sensor.

We wanted an advanced display with a silly number of features. Some did not appear to make sense, like deactivating the torque sensor, but they made each one of them.

It took way longer than expected, but amazingly at the end of the day it works! And its a beast and there is nothing like it on the market.

We feel that this is the maximum speed that this work can be accomplished in this industry for a production product. We know many full bike manufacturers are trying to pull off the holy grail - the 1,000W, high speed, geared hub, torque sensing e-bike.

There are many challenges and its very easy to walk into the ring and get punched out right away. And this is just on the motor side.

Battery issues:

Another huge challenge is the battery. To power such a motor you need a huge battery, there is no way around this at the moment until scientist invent a better battery. For now we have to work with the materials that are available or the bike will never come out.

A huge battery takes up lots of space on a bicycle frame. We wanted the battery to look as slick as possible, to be backwards and forwards compatible with every bike we made and will make, be lockable/removable and sit integrated low on the downtube. The pack cannot interfere with the optimum frame geometry for pedal powered bikes as we want it to feel like a real bike.

The capacity needs to be around 1KWh with readily available cells. Such a battery just does not exist on the market.

Basically most everyone making factory-assembled e-bikes in China buy the battery case and tube and welds it to the frame and boom, we are in the e-bike business. The pack sits either integrated, bottle style, or rear rack style. Some are making triangle type, but they are normally not removable which makes it difficult for us to service and was ruled out.

So all the e-bike start looking the same. This happens because it is expensive and time consuming to make a battery case. There are companies that specialize in case making and you must only buy it from them.

But what if we want more battery capacity than already exists? You can use multiple batteries which we ruled out as being too goofy of a solution... Or you have to make it yourself and this is exactly what we did to reach our performance targets.

This route is very much going against the grain, difficult and full of challenges. We had to figure out and solve all of these challenges but the result is incredible. It has 1kWh of energy, nearly double what's found on the average e-bike. The larger case has room for a massive 45A BMS, nearly double that of the average e-bike battery. It can super charge at 10A, that is 4 to 5x faster than most e-bikes are doing. It works on just about every "Current" series e-bike we have ever made. And sets the platform for future expandability.

Rather than make the case longer which is what everyone else does, we made it slightly wider and shorter. This way we could fit the huge 12 Transistor controller into the frame of the bike so it does not need to be unsightly or strapped to some part of the frame like a wart.

This downtube style of case usually have the cells stacked like roman candles. This configuration is a massive headache for battery suppliers and they really hate to do it. We literally turned things on it's head and put the cells sideways in a grid so they can be automatically welded and easily fit into the case. It sticks out to the side a little bit (which we will fix later) but the compromise is well worth the performance.

We developed this somewhat in the open and already found some supplier presented the 3D printed clone at the trade shows. It really does not matter, because in China, everything is a copy and if you made something that is not copied, it just means that there is no money to be made from that product at the moment.

GPS integration:

The battery packs now all have GPS integration capability. This is real tracking, sending actual coordinates data over the GSM network with its own sim card. This is insanely awesome as you can get a notification when someone so much as just touches your bike. If the crook rides off with it, they WILL be tracked down.


Some people noticed the brakes. The brakes are mechanical and that is due to lead time. Hydraulic disc brakes are harder to get hold of and dramatically increases the time it takes for the bikes to get to the market and most of all the good ones are made in Taiwan and have to be imported to get them to China. This double import is expensive and time consuming. It will improve later, but this is the current situation.

On the CrossCurrent we used the HD-715 hydraulic disc brakes. Those are like some of the highest performance brakes available. We put them on our mid-grade bikes and this reduced the speed at which we could manufacture the bikes. Braking is very important but unfortunately sits way down on the list of things people find valuable. Now we use decent mechanical disc brakes and give the option to upgrade the brakes.
First round of HyperFat frames rolling off the mass production line. XL (6'0"-6'4") / Med (5'2"-5'6") / LG (5'8"-6'1") - L to R as pictured
Frame size options:

The frames now have 3 different sizes. This has been a huge challenge and I will go into this and many more details later.

For now I must get out of the country today and get my visa reset so I can come back and help with the production of this unique e-bike.

Again we sincerely apologize for the delay and lack of communication recently in making this e-bike.

For current pre-orders in the system, the recent price adjustment will not affect you and your order will ship according to spec and the price listed at the time of your pre-order. Only following orders will be effected by the new price.

Initial bikes will come to the USA and be inspected then sent to the very first orders - in the order they we're placed.

The following orders will be assembled early to mid September and after completion will be sent by air 7-10 days or sea 24-30 days.

Thanks for your patience! More updates to come.

- Tora

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