BionX Kit Questions

[wizardofozzz]

I have a few questions about the Bionx kits (specifically I'm looking at the 250 rear kit).

First, here's some background. I live in a very hilly neighborhood and can't ride around without having to walk my bike up all the hills. That's no fun so I end up not riding much. I'd like to put a electric kit on the bike so tried out the electric Trek at my local bike shop and loved the pedal assist feature. I understand that Trek uses the Bionx system and am happy that they sell it in a kit. However it's EXPENSIVE. I need some questions answered so that I can talk my husband into getting a BionX kit rather than one from ampedbikes or ebikekits.

Here are my questions:

1. I thought I could perhaps buy it without a battery and have my husband, who is an engineer, make a cheap yet light battery for me. But apparently BionX systems require that you use their battery. Why do you have to use the BionX battery? I need specifics that my husband will understand.

2. Do any other kits have this pedal assist feature? What about a hack? Can you turn an ampedbike or ebikekit into a pedal assist (not cruise control)? If so, how?

3. Is the BionX kit really worth paying so much extra for? Is it that much better than a simple throttle system? I don't care about the regenerative braking. I just really liked the pedal assist feature, but mabe it's almost the same to use a thumb throttle.

[deardancer3]

Welcone to Endless sphere!

I am a retired engineer and worked in a Bionx shop for a while, and helped with one of the biggest shops in the US. I have done work on 6 or more different style ebikes.

My wife loves her bionx and would not consider anything else. She has a 250w on a 20" wheeled folding bike.

However:

The Bionx is a proprietery 'distributed control' system. Everything sits on the CAN Bus. The battery has a bus interface model that communicates with the rest of the system for on/off, regen, battery status, and other things. You really cannot do your own battery easily on a Bionx. You have to have the proprietary bus interface module.

There are no other "pedal assist" kit sytems as good, but really its not that important.

The bionx system is very good. It has lots of features, and is very light weight. It is one of the most bicycle like of the kits.
It can be kind of expensive. However if you love the features, have trouble fixing things, and value the lightweight bicycle like feel, the money may not be a big thing. but if you like to tinker and modify things, Bionx is not for you.

If your hubby is an engineer, is good with working in the shop and designing stuff, he would be better off to buy a starter system, get involved with all the tradeoffs first hand, then configure his own design to go for your specifications.

The Bionx is a nice user system. It is for riding. Kind of like getting an Apple computer vs an HP.

This can become somewhere between a hobby and a passion. Maybe start with the "3 minute installation" system to start?

d

[alan]

I have a few questions about the Bionx kits (specifically I'm looking at the 250 rear kit).

I'll try to answer your questions. I am a Bionx customer, and have about 4500 miles on a PL350 that is just over a year old. I am an engineer, too, and have no other relationship with Bionx.

1. I thought I could perhaps buy it without a battery and have my husband, who is an engineer, make a cheap yet light battery for me. But apparently BionX systems require that you use their battery. Why do you have to use the BionX battery? I need specifics that my husband will understand.

This is a hard one to answer simply. The Bionx throttle/readout/user controller, what Bionx calls the controller, is very sophisticated, useful, and well built. Most ebikes have an on/off switch (often part of the battery pack), a twist or thumb throttle, a brake lever sense switch (to cut power when braking), and a multi-LED battery charge indicator. The Bionx controller includes the on/off switch, power adjust switch, speedometer, odometer/trip/timer/clock multifunction readout, multi-segment battery charge indicator, and a power demand indicator that shows assist or regen amount. The brake switch plugs into this controller, and this controller plugs into the battery. This controller is also used to set many programmable values in the system (such as pedal assist sensitivity, regen rate, wheel size for speedo calibration, etc.).

Where most ebikes have an external power controller which switches the battery current to the motor windings, and contains the electronics necessary to properly time the power controller for the motor control, Bionx puts the controller inside the motor housing, but has some of the electronics inside the battery, along with battery protection circuitry. The division of electronics between the throttle controller, motor controller, and battery protection is unusual, has advantages for Bionx. It also makes it incompatible with most other systems. I can only speculate why Bionx is designed this way, and some will say it is to prevent customers from using non-Bionx batteries, but I can think of various engineering advantages consistent with the rest of the apparent Bionx goals for the best ebike solution that would dictate the division of electronics like Bionx has.

2. Do any other kits have this pedal assist feature? What about a hack? Can you turn an ampedbike or ebikekit into a pedal assist (not cruise control)? If so, how?

I believe most companies call this pedelec, and I also believe it is the only kind of system that is legal in many european countries. Trek is packaging the Bionx system on three models of their bikes, and charging more than full retail of the base bike and the base Bionx system that they are integrating. It looks like they have added a few "body" pieces to hide the wiring. Other companies also sell pedelec type ebikes in the US. Giant and Schwinn are two that I've seen in my LBS. Pedelec is usually done with a torque sensor inside the motor housing on a rear hub system like Bionx, or with a torque sensor inside the pedal bearings on front hub systems like Giant and Schwinn. I can say that the Bionx pedelec works great, and I rarely use the throttle. Most systems offer one or the other, while Bionx has both.

3. Is the BionX kit really worth paying so much extra for? Is it that much better than a simple throttle system? I don't care about the regenerative braking. I just really liked the pedal assist feature, but mabe it's almost the same to use a thumb throttle.

I think the Bionx is excellent, and not a bad value. It is designed well, well made, works great, and is a quality system. There are more expensive systems on the market that I think are not as well made or designed, or as complete of package as the Bionx. Bionx does not offer anything low-end. I have ridden inexpensive systems that work well, and there are many ways to save money over the Bionx systems, but I also think there is quality and value in the Bionx kits. I would say it is a bit like the difference between a Toyota Camry, and the $7000 more expensive Lexus ES. There is value in the ES, but you have to pay to get the extras. If you want the extras, you are unlikely to find it as cheap anywhere else. If you want loads more power, or more speed, or something else Bionx does not offer, you will have to pay well for that, too.

Like you, I was not really interested in the regen. However, I now LOVE the "power" brakes! About 80% of my braking is regen only, and it is addictive, much like power brakes in a car are addictive (if you are old enough to have driven a car without power brakes, you will know what I mean!).

-- Alan

[itselectric]

Here are a few video link that explain inside of the Bionx, how the system work, installation guide, etc...

http://www.youtube.com/watch?v=ka6-8Gdcg1g
http://www.youtube.com/watch?v=5qXjEgAoQdI
http://www.youtube.com/watch?v=33uCs_awBJk
http://www.youtube.com/watch?v=eSFE151tRdM

1. you must use bionx battery. If you want to bypass it using other type battery, you need to have an old circuit board and disable the regen system. It is a long story which require a new topic just on this subject.

2. Other kit had pedal assist feature? But there are nothing on market like a bionx. It has a patented proportional assist system (software driven), which mean it is very natural when you pedal, it will give you portion of the assist that you need. It's almost like the motor was never there. This is one of main feature that set apart from every other conversion kit on the market. To make a hack job on other kit will feel just like a hack job. There are no comparison with any other products on proportional assist.

3. If you want light weight, natural pedaling, well integrated system and you can afford it, then Bionx is your system. On the opposite side, if you want customization, more torque, more speed, more power, more distance, cheaper battery, other type of conversion kit is the way to go. If you want light weight motor but don't want to paid the same price as Bionx, then BMC 600watt or BaFang would be my suggested alternative choice.

Ken

[dogman]

I've never ridden the bionx, but have many many miles on the throttle based kind of bike. I found getting used to the throttle took 2 seconds, for me anyway, since I've ridden motorcycles for years. But really really getting to where I wasted no power, and pedaled along getting the maximum out of both my pedaling and my motoring took about 2000 miles of riding.

Now, with 5000+ miles, I use a throttle and the pedals together so naturally that I may as well be riding a bionx, but at first, I blew a lot of battery for no reason, or got nothing out of my pedaling, etc as I constantly had too much or too little throttle on to match my pedaling. I suspect a lot of riders would end up in that stage of inefficient use of the ebike for a long time, if not permanently. So the bionx, if you can afford it, may be a really worthwhile system to have. Go directly to ebike heaven on the first ride. What bionx needs to have though, is a place where you could plug in a second battery in paralell, for longer trips. That is where the proprietary stuff can be a problem. Using the lowest level of assistance makes a bionx go a long way, but having an ebike is all about having a larger assistance level to me, especially on hills. No problem though, if you ride distance is relatively short.

Adding pedelec to a regular motor kit is not that common in places where the law doesn't require it. I suspect that is because it doesn't do that much for you that a regular throttle can't do. Same thing with the ebrakes, you get pretty used to just not putting on the gas and the brake at the same time, just like on a motorcycle or your car.

[wizardofozzz]

Wow. These are great responses. This is exactly what I needed.

I went down the bike shop again and tried all of the electric bikes (the battery was dead on some last time). I tried the Urban Mover and it seemed downright dangerous. The second electric bike was also a throttle type but it didn't propel me forward with nearly the force of the Urban Mover. It was okay except that every time I peddled, it put in so much power that you wouldn't really get any fitness benefits from it. I still like the Bionx system on the Trek the best. I just wonder if there is a way that the bike shop could have tweaked the throttle type bikes so that they could sell more of the Bionx bikes which are twice the price.

[liveforphysics]

A year or so ago, Methods called me and told me I needed to try an E-bike. I called around and finally found a shop that had a few. For myself, riding a bionix kit made such an impression on me about how electric bikes feel, it nearly killed off my interest in the concept of an E-bike.

I hated the way it applied it's meger power in pulses as I pedaled. Even when dialed-up to max, it still felt like I was pedaling a bike around. I felt only minor performance advantages over just riding a lightweight roadbike, except it had the crappy handling of a +50lbs bike with a hubmotor.

Then I tried a cheapo 500w geared hubmotor bike with a throttle. Yes! This was the feel I wanted in an electric bike! It felt perfectly natural and logical to ride after the first 10 seconds. It was the feel I wanted (except I wanted 20-30 times more power). It showed me that an electric assist bike could feel pretty good, and that was what it took to inspire me to do my bike build. This rapid fondness likely was influenced by my body having 20 years of mastering the concept of twisting the wrist to control the power you want to send to the wheel, which feels as natural as walking at this point.

[dogman]

Yeah, like me, an old biker takes to a twist throttle like a baby to the tit. But a pure cyclist finds a throttle very wierd. I just had a long time adjusting to the idea of using less than max throttle. Really good pedalers find the pulsing hardly noticeable while a less smooth guy will really feel the pulse. But I agree, the weight penalty of the motor needs to come with more power or it may feel better to pedal a light bike. Once I got the feel for proper use of the throttle, I can make my bike feel like pedaling a 5 pound bike by applying just the right amount of throttle. But that level of finesse takes longer than with a bionx. And it took miles before I could really do that without thinking aobut it.

[dogman]

Of course, pick the bike up and it will feel like every pound of its 85 pounds. Running a front hub as I often do, the front never feels light, with a 20 pound motor on there as sprung weight. The best comparison I can think of is it's like wearing heavy shoes but if you are walking downhill they don't bother you.

But the pedaling effort can be like the bike weighs 5 pounds, or you lost 30 pounds, whatever. I don't notice any effects from the weight when cornering, but curb hopping gets harder. The sweet spot is when you pick a motor speed, and pedal to go 1-2 mph faster. Then the motor gets real efficient, and you don't have to work all that hard.

[Takemehome]

................ The sweet spot is when you pick a motor speed, and pedal to go 1-2 mph faster. Then the motor gets real efficient, and you don't have to work all that hard.

Dogman,
That's how I use the cruise control.
I set it to 20kph and then pedal to go 25kph.
That way I use around 9WH/Km.
Good exercise + good range.

[DahonElectric]

As an owner of a Bionx as well as a 9C (throttle type), the Bionx is fun to ride with. The open throttle system is flexible -- you can change anything you want and you get more power.

If you are a seasoned cyclists who spins smoothly, go for the Bionx bike. Spinning smoothly reduces pulsation on the motor as one other poster mentioned. If you simply want to get a motorcycle riding feel, then go throttle. It's as simple as that..

DE.

[deardancer3]

That feeling of pulsation can be moderated thru one of the many Bionx software adjustable settings.

The register address for that is #1234. Stock, its contents comes set equal to 4, the most sensative setting for the pedal sensor.

most people like a setting of 2. Real smooth strokes can take a 3, extremely rough stroke 1.

We use a 2.


best

d

[wizardofozzz]

Okay, now my husband has tried both the bionx and throttle type bikes and says it's really up to me. He can see why people like the BionX. It's a nice system.

So, now I'm trying to decide if I should buy an ebike kit or if it's really worth it to get the Bionx kit which costs several times more. Can I really justify that?

Last night I had decided I would just go for the ebikekit - mostly because it's soooooooooooooo much cheaper. But, the bottom line is that I want this bike for fitness (but I need some help with the short but steep hills). I'm concerned that the ebikekit will do all the work for me and I won't get much of a work out.

Decisions!!

[Russell]

Okay, now my husband has tried both the bionx and throttle type bikes and says it's really up to me. He can see why people like the BionX. It's a nice system.

So, now I'm trying to decide if I should buy an ebike kit or if it's really worth it to get the Bionx kit which costs several times more. Can I really justify that?

Last night I had decided I would just go for the ebikekit - mostly because it's soooooooooooooo much cheaper. But, the bottom line is that I want this bike for fitness (but I need some help with the short but steep hills). I'm concerned that the ebikekit will do all the work for me and I won't get much of a work out.

Decisions!!

If you want an E-bike for fitness I would recommend buying a small geared hub motor kit. A 36V 250W Bafang or GM Mini Motor in a 26" wheel with a lithium battery will provide some assist up to perhaps 20 mph and move you along at around 16-17 mph on the flats by itself but it won't overwhelm you. A low power system is ideal for fitness rides since often times you'll be cruising at speeds just above the capabilities of the motor by itself so you'll naturally be providing a good portion of the propulsion then when you do hit upgrades you'll slow down and the motor will provide more of the power. A higher speed and more powerful motor such as the 9C can be ridden in a similar fashion however it takes a lighter touch on the throttle. Also a lower speed set-up will be more efficient requiring a smaller battery. A lot of E-bikers get caught up with going much faster than normal cycling speeds which requires a bigger battery and a bigger motor and more weight however if you're in no hurry and just want some assist everything can be scaled down which results in a lighter, cheaper, more efficient E-bike and the most "bike-like" riding experience.

-R

[Takemehome]

........ I'm concerned that the ebikekit will do all the work for me and I won't get much of a work out.

The throttle is not a ON/OFF switch and you don't need to go FULL throttle.
Look at it this way:
Bion-X = You tell a computer to give you a certain help factor ( 1 to 4 ) and the computer does it perfectly.
eBikekit = You tell your wrist to do the same task and it does it approximately.
Now, is it very important to know exactly how much % the motor helped you ?

[deardancer3]

if you like the idea of having limited assist, here are a few concepts that could be of value:

First, try looking at this, a way of temporarily limiting the maximum assist from the throttle:
viewtopic.php?f=2&t=13835

It could be set up so that the limit could be defeated, giving full power if needed. The limit could be variable, with presets.

Another is using the "Cycle Analyst" for preset and variable maximum power. It is expensive in comparison to the first option above, but, also gives a speedometer, watt hour meter (gas gauge), amp meter for current power used, and troubleshooting tools.

http://www.ebikes.ca/drainbrain.shtml

d

[DahonElectric]

Decide on the price you want to spend on and stick with it. You're going to get some exercise regardless of which ebike system you ended up with, so don't worry. Bionx is a luxury system and is not meant to be affordable for everyone either, because of its sophistication on the computer controller side which the ebikekit doesn't have. I own a similar ebikekit (it's a 9 Continent 500w motor) with a Cycle Analyst and I like it. It rides differently than my Bionx. As a pure bike rider, I prefer the Bionx because it just syncs with your pedal stroke (once caliberated properly as per deardancer3) as though you are truly riding a bike but with legs of Lance Armstrong. Whereas with any throttle control bike, it rides like a motorcycle. We had an intense debate which is better a few months back about this, so I rather not beat a dead horse twice. Suffice to say, go with what you can afford and be happy with it.

DE.

[vancamp]

The sensation of "riding a bike but with legs of Lance Armstrong", which I also get with my BionX bike, is so fun that I just want to go out and ride (exercise), rather than having to force myself to do it. So it has worked very well as exercise motivation. Don't discount the value of that feeling.