General E-musings.............

I have been thinking about our beloved hobby quite a bit lately and have a few observations to share. These may not be the same observations as the rest of the E-community has, but these are my personal reflections and opinions regarding bikes, electric transportation, and E-assist specifically........

I have been riding E-bikes for over 2 years now and have logged roughly 2,000 miles on them. In that time, I have built and ridden many different styles of bikes with modest power all the way up to stupidly ridiculous, insane, "I am going to die!" power. I have ridden on 50mph roads, 20mph roads, in traffic, on deserted roads, new roads, old roads, with much pedalling, without any pedalling, and overall I think I have covered most situations possible with a bike (both assisted and unassisted).

My observations;

First, I do not like riding a bike without doing any pedalling. I know this is not everyone's perspective, but it is mine. I like to be able to pedal for exercise, increased battery efficiency (longer range per charge), increased top speed, (OK, only 1 or 2mph additional) and for the stealth that pedalling adds to the E-bike rider.

Second, I do not like all the added weight of a bike with lots of added equipment. My yellow trike weighs 105 pounds. Now, while that is still not too much to pedal, it is definately too much to enjoy without always being on the power. While my recumbent and my Catrike are light weight (49 and 60 pounds respectively). These bikes pedal almost like there is no electric equipment on-board what-so-ever.

Third, I enjoy high efficiency more than pretty much any other aspect of this hobby. My Catrike goes as far on 10ah as the big powerful yellow trike goes on 30ah. That is a pretty big difference. Also, efficiency drastically reduces build cost, time, and weight of the bike because of less battery that is required. On top of that, pedalling gets you much more with less weight on board than trying to pedal a heavy vehicle. So, with better efficiency you have less weight, the bike costs alot less to build an maintain, is far easier to pedal, which in turn gives even better efficiency overall because you can add more miles pedalling because the bike is so much lighter.

Fourth, being ambasadors for this hobby (as we all are), I like to be as stealth as is absolutely possible. If someone asks, I will show them the assist. However, I do not want to call attention to myself unless I have to or want to at the moment. This makes us all more respected and creates an atmosphere of welcome to E-bikers, rather than calling attention to ourselves with super loud, super obviously obnoxious bikes.

My conclusion of the ideal E-bike application and their overall contribution to society is;

#1 RC bikes are not the end-all be-all of electric bike systems. All setups (yes, even Frock setups) have their place. I do think, however, that RC systems have the best power to weight ratio and efficiency available. This makes them ideal for me, at least, and for anyone else who likes a bike that is still light weight and pedalable as a normal bike (they are expensive, though).

#2 Electric transportation is very valuable for many reasons. It provides an opportunity to focus on efficiency not otherwise looked at if using a fuel burning vehicle.

#3 It gets us out into the open air.

#4 The best setup (for me anyway) is good for pedalling as well. This provides much exercise. Also, with assist, the amount of exercise is chosen based on how much throttle you give to maintain a given speed. This is fantastic from a training standpoint. You can get the amount of exercise you are looking for without arriving at your destination too hot and sweaty.

#5 It affords us the opportunity to ride a bike while having a leg unjury, being too tired to pedal, or even for those with disabilities. This is a fantastic facet of this hobby rarely discussed! I love going for a ride when my legs are fried and still being able to cover my favorite route without adding any more leg strain. I tore the Meniscus in my right knee 7 weeks ago and my E-bikes have allowed me to ride while only giving as much pedal input as my knee is confortable with. This has been the greatest therapy I have ever had and, trust me, I know. I tore my left knee 20 years ago and did not have this as a therapy aid.

Anyway, I am rambling on and on. I just wanted to share my findings with you guys and see how many of you feel the same way and what other bits you have to add.

Matt

I'm with you, Matt. I only really need power-assistance for accelerating and climbing hills. I see it as an alternative to wide range pedal gearing - add torque rather than gear down.

E-bikes have been the best hobby I have ever ventured into. There is no better feeling than cruising around town on a bike that you made yourself.

There have been some very impressive projects on this forum, and I know there will always be better projects to come! I am very excited for the future!

I've got to admit that I'm suprised by some of your observations Matt, since I associate you with some great high speed builds, but I agree 100%. I pedal virtually all the time by choice, find slower speeds are not only more comfortable, but allow interaction with both fellow cyclists and others that are walking, etc., and believe that staying legal will help the e-bike community in the long run.

It is great being able to go anywhere (except you can't use the electric assist on sidewalks in Oregon) that regular bikes are allowed. My feelings are that if you want to exceed the legal speeds set for e-bikes you should build a moped or motorcycle, license and insure it as required, and stay off the multi-use paths.

At age 70 the future of e-bikes probably won't affect me very much, but with a 15% grade on the road to my house I really enjoy the electric assist.

In a few weeks I'm riding in a Metric Century where there will be hundreds of other bikes. I may well be the only electric assist there, and my buddy and I will probably mossy along at 10 to 12 MPH. I plan to do the 65 miles on less than 750 WH, so a fair amount of pedal power will be required.

These are all great points! I definitely agree with all of you.

My setup now is a rigid Trek 830 with 25ah and Matt's drive with a 3210. This bike is very efficient. I can see 60+ miles on a charge because I pedal between 21 and 25mph with the road crankset I put on it.

That being said, my former setup was a 130kv HXT 80-100b with 10ah, geared at 10.29:1. You all are thinking it or else you have experienced the fact that this bike was set up for failure. It failed... right after one of my most memorable rides. This motor was powerful and I didn't really feel like pedaling it with my 44t chainring on my crankset.

It was a beautiful day when I was riding down New Hope road, a couple miles from my house, at about 35mph and I happened to notice a posse of 3 Earth-hating, up to no good, gas usin' fools on mopeds. I slowly crept up on the unsuspecting victims when my heart started pounding a little harder and I developed a slightly sadistic grin underneath my black, identity concealing, full-face helmet. As I twisted my Magura, I accelerated up to 40, 41, 42, until I hit about 45mph right when i passed them all. The poor kids didn't know what hit them. It was the most gratifying feeling to know that I just passed these guys on mopeds with my homemade electric bike, only to leave them wondering what the heck I was riding.

Shortly thereafter, I turned left onto Cramer Mountain road, a winding descent for about half a mile. I slowed down to about 25mph and waited to see if these guys would ride up beside me. Sure enough, they did. One said "Dude, that thing is awesome!" Another said, "what the heck is that thing???"

It was a cool feeling to stun those guys by telling them I was on battery power! During our brief encounter one of the guys slipped on down the twisting road. A few seconds later we all went down. I blew by the remaining two kids, placing the bold, yet naive rider in my sights. I felt like a motorcycle racer as I was leaning into the curves of the road with one objective: seek and destroy (except just pass instead of destroy). I leaned left, leaned right. He kept getting closer and closer. And finally, I raced past him just before the last curve of the stretch.

Success. My vehicle was not only more efficient than these fume blowing mopeds, but faster... I was one happy ebike rider.

That wonderful ride may have been the demise of my HXT, but those other guys don't have to know that...

Daniel

sounds like the Kepler drive has all 4 point covered well then!

I enjoy the pioneering aspect.

It's like hotrodding's prime days of trying new ideas and experimenting (I wish I was born in the 1930-40s sometimes lol). Anyone with a good idea they are willing to invest a relatively modest amount of cash towards is able to press into uncharted waters of LEV development.

I enjoy the open and unrestricted options. No government state-patrol inspector has to approve what you build, test your emmisions etc etc.

I love that it's a vehicle I don't get stung with a hundred bucks a month to keep insurance on, or to keep a licence plate current etc.

I love knowing that if my licence gets suspended, I've still got fast and fun transporation to work available with out having to drive on a suspended licence.

I like that the work we do paves the way towards better transporation solutions for the future. The work done here by the people developing, both on projects that are failures and sucesses all lay out valuable examples and emperical test data for folks to build upon. Just in the short time I've been on this board, I've seen huge improvements in the groups (and my own of course!) understanding of obscure but critical properties and functions of motor/controller/battery systems. The hard-earned knowledge and skills we're discovering every day on this board will be critical to mass adoption of EVs for transporation.

Well, as most of you know, i can honestly say that i've been there and done that, now what ? lol..

Seriously speaking however, low speed ( 20mph ) and low power ( 1000w peak and " 500w " continuous ) are what the general public will come to accept as power assist the way it stands now.. just like a large majority of the population is perfectly content with 4 cyl 4 door family cars.

So, to that end i fully agree that no one system will be the be all, end all, of ebikes..

Over the last, oh man, *thinking back.. ... ... ... 6 years !? .. i've tried pretty much all hub motors on the market, at everything from 24v to 100v... i have one RC bike with moderate performance and have a good understanding of the possibilities .

My personal opinion here is that hub motors are the winner for almost all but the most hard core fanatics. :lol:

I have no idea how many 1000's of miles i've racked up over the last 6 years but it's a hell of alot more than the pedal only miles i've done in my lifetime.. if it was not for the ebike experience i'd likely own a car at this point.. but i don't.. and even if i have seriously considered it i think i'll be car free my whole life.

Next step for me at this point is the electric motorcycle. A few of my " ebikes " are pretty much just that.. but as a business venture i see a future in the ev motorcycle market more than the ebike.. why ? .. well.. because pretty much any joe can convert a bicycle but building an electric motorcycle is more of a challenge that not many will ever attempt but alot would ride them if they were available.

How much of the RC motors are made in the USA? I am not anti free-trade, its just that there are no hub-motors made in the US, so whenever fuel prices spike up, the economy takes a dump, and there is a sudden shift in parts availability.

By that I mean that hub-motors are suddenly sold out, and I "assume" RC model sales slow down. (leading to an RC-motor glut, and clearance prices?). Regardless of where the parts for RC motors come from (of course, locally is better for me), I'm certain they will play a big role in the next wave of E-bike interest.

Towards that end, I am sorting the parts needed for 500W-1,000W friction drives using RC-motors, and Left-Side-Drives for power levels above that (similar to Bubbas build 5). All will have the option of a fan-cooled box to help quiet the drive a little.

Matt, you make the Corvettes of E-bikes, I hope to make a few Ford Model-T's for the local college students (Central Kansas). I hope to have a few kits that are sellable by next spring.

Hi Guys,

I'm with Matt with all of theses points I really like to pedal my ebike and my Black Arrow is too heavy for this. But the handling and carving on this ebike is fantastic at any speed and the top speed is really great.

I'm actually thinking of building a new light ebike with a 1000 to 3000 watts (peak) RC drive style set up, something like an Optibike with almost the same component Fork, Shocks, Wheels with a Lipo 48 Volt 20 Amps pack to keep this ebike light with an insane range at pedalling speed.

It's my 2 cent's thanks Matt to starting this reflection is fun to read what other members thinking about it.


Good day!
Black Arrow

Hi Matt

Yes came to the same conclusion years ago mate! after building my first heavy but fast bike using the Lemco motor and gearbox and all the other motor kits that I have played with and still have I still find the simple lower power rigs are the best for all the reasons you mention, I also love to peddle as well and agree 100% with you on that front.

The bikes are so much more reliable as well, take the BMC motor, keep the power below 1600W and they are reliable motors, very light, powerful and efficient, I have clocked 3,000 + miles on 1 motor, ok I have had failures but that was when I was over volting them though.

I love this hobby! however I dont like to have to keep on repairing things and or buying new parts so I have taken time to find the sensible limit and I don't push it over that, with this approach I have a stable of fast and very reliable bikes that just work and don't break, they are fast and reliable and efficient I get great range as I am strong peddler.

The only thing that I don't agree on is the efficiency of the RC systems being better than hub motors and Y pedal has confirmed that this is not the case as he has both systems, Hub motors are not as bad as folks make out and we need to get away from the stupid name calling that they have seem to have attracted, direct drive hub motors are a fantastic and simple device that work and for the large part dont break, they consist of 1 moving part there aint much to go wrong.

Whist I like the RC based stuff for its stupid power I dont think it has anywhere near the level of reliability it needs to take off and become mainstream, the controllers and the motors are just not there yet IMHO I still dont see how some of these little motors can possibly carry such high levels of power and stay efficient, from what I have seen they run very hot and controllers and motors fail, there isnt enough of them compared to hub motors to make a fair comparison though.

I think that things have got a little bit crazy with the power some of the builds have got to hey matt :lol: so its nice to see you have come to the same conclusion 8)

Knoxie

If I recall correctly, Y pedal was also pushing an overgeared Astro motor through three or four stages of reduction. Not the most fair way to test the efficiency of an RC type drive.


I certainly concur, but I also have been leaning towards light motorcycle builds. I really like me some mopeds too.

Yes, Y's build is the worse case scinerio. He is overrunning a 3210 way beyond its efficient point, through 4 reduction stages through a Nuvinci hub. The hub, alone, destrys efficiency. That being said, I like his torture testing!

My efficiency on my recumbent and my Catrike is 14 to 15wh per mile. It is down at 12wh per mile if I stay below 20mph. That is what I call efficient.

I know many hubbies are plenty efficient, though. However, I find it interesting that the worst scase scinerio is always quoted for efficiency.

My big yellow KMX is more efficient than Y's bike and has 4 times the power. I am not criticizing Y's bike. I love that build! I just want to point out the fact that he is definately the worst case scinerio as far as efficiency goes. Of course, he is having huge fun with it, so, hey that is cool. 8)

Matt

Yes agreed however to get these motors to spin in to efficient ranges you need high rpm which isnt how most ebikers ride and methinks this is where most of the reliability issues come from low rpm use causing excessive motor heating and controller failures, I agree that hub motors are also not good at low rpms however they can be with sensible use of the throttle this can not easily be achieved with the RC motor setups from what I have been reading.

There are pros and cons to both types of systems and I am sure in time the RC systems will find their level in the same way that I did with my builds, this thread isnt a hub vs non hub argument, it is one of generally lower power lighter more efficient rigs are the way forward for power assist we need to remember the assists bit with bikes, if you dont want to peddle make it a motorbike, fit it with a motor and controller that can make the trip.

I think in time unless something changes that folks will jump one way or the other, either way there is room for low and high power rigs the middle ground will always find favour as the compromise between reliability and usable power always favours high power tuned rigs with low reliability.

lol.. my RC setup draws 350w with the wheel off the ground ( 6.x amps at 50v ) .. half throttle is still 250w .. so the Nuvinci and all the spinning belts and chains take their toll obviously. The bike is far from perfect but has been holding up well for what it is.

On some of my bikes like the A2B Metro, pedaling is a pleasure, but as soon as you pass the 30mph mark i prefer to concentrate on my riding and less on the pedaling. :wink:

To me most of the various points brought up are just variables; there can be low power ebikes, high power, geared hubbies, DD, RC, various transmission solutions. Good ebikes can be built with any combination of these.

However one of the points is crucial: Weight. If it's heavy it's simply not a bike. Too many people think of the bike alone, but it is really the bike-rider that makes up a dynamic system. Now consider a few pursuits:

Skiing: 80kg Human wears 1-2kg skis
Biking: 80kg Human rides 10-15kg bike
MC: 80kg Human rides 100kg motor bike
Car 80kg Human drives 1000kg car

In the first case it is clear that the human controls the skiis through whole body movements. Since the skier can move the ski sideways, fwd/bkwd, up/down, and turn it around any of it's three angular axis, each ski has 6 controllable degrees of freedoms (DOF). The skis can take a quite complicated trajectory down the lope. Watch a slalom race, especially with closely spaced gates.

By contrast, in a car, however much you jump around inside it will have negligible effect on the trajectory. (Luckily for parents with kids inside...) The car is only controlled laterally through steering and longitudinally though accelerator/brake, hence it has 2 controllable Degrees of Freedoms (DOF).

Bicycles and MC's have a middle ground, but a bike being so much lighter than the person is much closer to skis than a heavier motor cycle. Just the lightweight aspect of a bike gives unique manueverability. A good rider can twist it around anyway he wants. Good bikes are designed and tuned to perform in the combined human-bike dynamic system. When the bike fits like a glove then e.g. a light push down with your legs is all it takes to jump a curb in perfect control. In tight situations a bike can manuever quicker than a heavier motorbike.

So in short, to feel and act like a bicycle I think an eBike has to be about the same weight as a bicycle. A creation where a lot of weight is added to what was designed to be a lightweight bike frame is not going to ride well. I know this well from having started with a nice riding 13kg Specialized Stumpjumper and made it a dud by putting 17kg of motor + battery on. Yes it is a functional bike that has taken me though rain and shine (and snow) for the past year and a half, but fun to ride? Not as fun as it was before.

So what to do? Well, I'll have to see how my Cannondale builds turn out. Oversize (stiffer) frame tubing + minimized weight of ebike components so 15kg of bike is matched to 5-10kg of ebike parts. Hopefully I'll know in another season or two of riding if it was the right combination.

It will be interesting to look back to our current creations in 5-10 years. Maybe it will be like when we look at old computers: yesteryears big clumsy PC's to todays sleek, powerful laptops.

Hey Matt, your four observations of E-Bikes probably encompasses the core design considerations of most builds.

I've been floating back and forth between e-biking and straight up biking. I've got about 3500 miles in legs this year at a 50:50 ratio so I could really relate to your post. Pedaling my e-bikes is great recovery and makes me feel like superman. But I think that each type of bike is just begging for the right type of conversion. The objective is to enhance or extend the bikes original purpose. And some bikes might actually do well with - ahem - significant power.

So here are a few musings of my own -
Pugsley: Torquey Bafang BPM is fine with the high flotation tires.
Rigid 29er: Single speed it for me but drive it from the left side with a 3120 just like your trikes. (K.I.S.S.)
Road Bike: Kepler Drive should do it.
FullSus MTB: Single 3220 thru cranks for plush high speed commuting. (I live a couple miles down a dirt road. Need 56x11 gearing for the open road.) Can also offroad with a simple change of wheels. Low unsprung weight.
Long Cruiser: Either a small rear hub motor for icecream jaunts or a tire smoking set up for showing off since that is what the bike is designed to do.
Super Fat Chopper: That bike aint built for pedalin! So maybe beastly power is the only logical conclusion.
Wifes (pseudo)-MTB: Cheap/reliable hub motor so she can go 18mph and not have to work so hard. (She does NOT want to go faster. She told me so. )
BMX: The twin motored Ripper was every teenage boys wet dream. But if you try to ride it like a BMX bike I can't think of any setup that would last. So that one broke the mold.
Etc...:

I'm a little biased towards higher power since I've been averaging low 20s (mph) unassisted. And I like to stand and pedal every so often, even on e-bikes, so I'm designing some battery cases that will keep my bikes somewhat flickable. They will be easily transfered from bike to bike (and for off-bike charging at work). Not exactly stealth but 'in the down tube' is not an option - and handling for the first four bikes in the list takes priority over stealth.

To keep weight down I run LiPo. But I need enough for 45 to 60 min. of ride time. Since my wife likes to ride slower she can get away with less battery and I ride unassisted. So in many ways the bike has to be dialed into the rider - this is a big part of what keeps local bike shops in business - same need is there for e-bikes.

I added one to the list -
1. Pedaling makes sense for bike and rider. Both under power and not. (You know what I mean!)
2. Build as light as practical.
3. High Efficiency. (Tires & pressure is #1)
4. Stealth. (Visually and audibly.)
5. Handling must be not significantly altered. (Unless improved for higher speeds.)

But, under certian circumstances a creative design can trump all of the above.

liveforphysics said:

I enjoy the pioneering aspect.

It's like hotrodding's prime days of trying new ideas and experimenting (I wish I was born in the 1930-40s sometimes lol). Anyone with a good idea they are willing to invest a relatively modest amount of cash towards is able to press into uncharted waters of LEV development.

I enjoy the open and unrestricted options. No government state-patrol inspector has to approve what you build, test your emmisions etc etc.

I love that it's a vehicle I don't get stung with a hundred bucks a month to keep insurance on, or to keep a licence plate current etc.

I love knowing that if my licence gets suspended, I've still got fast and fun transporation to work available with out having to drive on a suspended licence.

I like that the work we do paves the way towards better transporation solutions for the future. The work done here by the people developing, both on projects that are failures and sucesses all lay out valuable examples and emperical test data for folks to build upon. Just in the short time I've been on this board, I've seen huge improvements in the groups (and my own of course!) understanding of obscure but critical properties and functions of motor/controller/battery systems. The hard-earned knowledge and skills we're discovering every day on this board will be critical to mass adoption of EVs for transporation.

Click to expand...

+1 +1 +1 +1, this is exactly what i've been thinking since i started reading about this. I like the wild west factor. I like the fact that there is a form of electric form of propulsion that i can afford, eliminating my car for some short trips.. And most of all, i like the fact that once i get my kit up and running i will no longer shy away from hilly rides or long distances. No longer will i question wether or not i want to take a 10 mile round trip for fun/exploring/excersize.

It is about as 'freeing' as when i got my first car when i was a teen ( gas was cheap then... ). Now a car is a liability, prevents me from excersizing, costs me thousands a year to own, and runs off.. sigh.. oil.

Here's to many more years of innovation, tinkering, and enjoying this novel form of transport.