Getting the most from 200w - Geared hub vs Mid drive Austral

[cycleops612]

Correction, you want something that looks like 200w (certainly not a direct drive hub).

you just get an ~official 250w 48v anything AND a 500wh battery, and dont you worry your pretty little head too much about power. it will somehow appear in sufficient quantities, almost by magic.

mate, if u seriously have that app to swap an ebike for a car for over a year, then hang the expense. ~1800A$ will be the best buy u ever made.

treat u self and get one u will love the fundamentals of, but importantly, dont risk having your investment trashed by not having a credible story and good behaviour for the local cops. who needs that stress. stealth is worth paying a premium for.

i did a posted a thread here on es - the worlds best ebike nobody has heard of ~

thats my bike, clearly i love it

24 gears, alloy, unusually, a direct drive on the pedal crank - check last photos in thread

u have to be careful about samples of one here, a swallow does not a spring make.

mid drives do add stress to the fiddliest part of the bike, the de-railleurs, and yes, over 500w and rough changes could make for annoyances, but nobody talks of breakages. You get home ok but some gears are flakey sorta thing.

450w mid drive is a nice balance. even 350w with a good battery is fine for me now. If i were heavier, i would want more.

Once your changes are smooth, a new chain & sprockets every 5 years is fine?

Weight is precious, speaking of which, u didnt state yours - important when asking advice. each extra kg requires more again elsewhere on the bike (less stealth).

mine is 75kg & bike is ~22kg ex battery. giys here dont think it worth mentioning that their advice is predicated on their 180kg weight situation. So yeah, a lot of BS to sort thru.

An option is to buy a wimpy mid-drive w/ crap battery 2nd hand & upgrade the controller and battery to highre voltage. the motors dont seem to mind much.

 

[cycleops612]

Unfortunately it gets worse.

The hardest is the battery. A very long story, but it seems we all only learn the hard way.

my advice, a 10ah 48v lifepo4 pouch cell pack, and get a bike to suit. I just ordered a 500wh in 36v form - ~A$400 all up from china. They take 8-9 weeks to come using now mandatory surface mail.

li-io (most common 18650 cell chemistry) sound good but are BS for the peaky demands of an EV & dont last

u dont mention if u can charge at work? Consider a spare charger to leave there?

Its ~all about wind. other resistance is negligible. A rough rule of thumb i like is, in ideal still conditions, it takes 100w to pedal a roadbike at 25kph (15mph). each extra 5kph takes another 100w & so, exponentially, on.

so u rightly dont expect, or foolishly desire, a rocket (but you will be pleasantly surprised at the torque considering), in which case, on a bike like mine, 200w ph should be fine for 25kph average, 300wph for 30kph & 400wph for 35kph. So a 500wh battery should cope fine, pedaling optional (a good assumption).

Similarly, Consider different handle bars etc.

consider electric gloves & jacket(or even cheap lo volt/usb warming pads from china - little electric mats), that maybe connect to the bike battery? gets nippy there i imagine?

 

[cycleops612]

A factor here guys maybe heat.

If the wind blows from the desert on ~3 sides, adelaide can be a furnace. 100f+ for days/weeks?

I imagine 48v helps by reducing current?

my other mid-drive (250w 36v) has problems on grades on hot days - dunno?

my good mid-drive is a direct crank drive motor w/ a housing integrated into the alloy frame (heatsink). it never gets warm even.

 

[Samd]

This is getting out if hand. There's absolutely nothing wrong with 18650s and the complexity of middrive fitment doesn't really fit the brief.


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[cycleops612]

This is getting out if hand. There's absolutely nothing wrong with 18650s and the complexity of middrive fitment doesn't really fit the brief.


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a 10 amp 36v 18650 pak produces 360 w for an hour, right?

BS. Its a lie.After 10 minutes on a fully charged new battery, my (just an example, most always generally true) 12 amp panasonic 18650 pak even, is nothing like it. Half an hour of full throttle and its as weak as a kitten.

lifepo4 is what it says it is. an hour of rated current, or less time and even more than rated current, and it degrades far less over time, and even that is more to do with already generous c-rates than capacity.

 

[cycleops612]

But samd may have a point - out of hand given job description.

I confess i had a lapse re the target bike being a road-bike, but he did prefer no pedaling, which aint gonna happen on a smallish hub drive.

a very doable option btw is a 2 speed xiongda hub motor. a hill climb gear and a cruise gear helps a lot. If they suit your axle widths and brakes, it could be a light (3.5kg) and simple option.

mainly my point is:

another approach is to think of it as a pedal on hills paradigm, but as the bike is a light roadbike and the hub motor, tho struggling in a bad gearing, helps with say 150w, only light pedaling is required (which helps the motor get into a better rev range). i.e. focus on keeping the bike light and slippery, so pedaling has maximum effect.

 

[Megsy73]

I think you just need to understand - usually cheaper mid drive kits require maintenance and/or fiddling about to get the most out of them over time. The more expensive kits, like Bafang or AFT, tend to be more durable. Bafang is also significantly easier to install and is very tidy given the controller is part of the motor unit. I'm not sure if they have a 200w unit, but they certainly have a 250w unit (which I have) which is very discrete.

Having said that, I'm switching to hub motors after being pretty disappointed with the lack of longevity and amount of overall fiddling with middrives. Each to their own....

AS Lurkin mentioned a 200w mid drive is legal and can make better use of the low 200w power limit than a hub, and is cheaper than a 250w legal complete ebike. But if you choose a cheap mid drive you will get lots of problems and the cyclone doesn't even have proper instructions ?? So not for beginners. Thats why the AFT has been popular as they have made that cyclone motor stronger and more efficient it seems. I have seen people on sphere have done like 9000 miles with the AFT kit. The 200w also has internal controller so clean finish too. Bafang doesnt have a 200w version i have seen ? And is less reliable then the AFT. So don't go mid unless you get a reliable one as they are more complicated and can be more problems if not done right...

 

[Sunder]

Are there any ni-mh ebike batteries available (ie. using d cells), ready made as packs with controllers? I read that some electric cars are still using them at over 90% percent after 100,000kms. How long would a lifepo4 battery last?

I built my first battery pack using NiMh D cells. I'd recommend against it. It was fine up to about 5km/h on the flats. The second you hit a hill, or needed more power to go faster, the voltage sagged and hit low voltage cutoff, resulting in a jerking forward movement. In theory, a much, much, much bigger pack might have solved this issue, but a pack of RC LiPos at half the size got me going to 40km/h, sagging only to high 30s up mild hills.

NiMh have terrible cycle life - around about 500 full discharges, or 800 for special "long life" NiMh. They fare a lot better when they have very low depth of discharges - such as in hybrid electric cars. The early hybrids basically only helped you accelerate - they wouldn't drive the car on its own. So you might only take 10% of the battery's rated capacity to start the car moving, then the petrol motor takes over and every downhill and brake you come across charges the battery up. In other words, in a hybrid, the battery is just a way to buffer momentum, (Stores energy from braking - uses it to start moving again) it doesn't "really" drive the car.

The 10% loss (and I'm skeptical it's actually that low) would have been almost entirely shelf life loss, not cycle life loss. So they were good for hybrid electric cars - can you name one fully electric car or plugin hybrid using them? Nope, because unless it's home made, there isn't one. There's a good reason for that - if you actually drove the car primarily by the battery, NiMh would be dead within a year. Likewise, NiMh will be a very poor choice for electric bikes, because you want to use the battery to actually drive the bike, not just buffer energy.

If you want long life and actually use the battery LiFePo4 will be the way to go. Choose a battery that can deliver around 3 times your peak draw and twice your required range, and the battery will last you at least 10 years. LiFePo4 has about 3000 cycle life to 80%:

 

[Lurkin]

...I think you just need to understand - usually cheaper mid drive kits require maintenance and/or fiddling about to get the most out of them over time. The more expensive kits, like Bafang or AFT, tend to be more durable. Bafang is also significantly easier to install and is very tidy given the controller is part of the motor unit. I'm not sure if they have a 200w unit, but they certainly have a 250w unit (which I have) which is very discrete.

With over 13,000 documented kilometers in commuting to work and back... the Li-Ion pack is performing perfectly well.... there are pros and cons to either chemistry, either way. In the OP's case, a nice pack with a BMS for simple charging arrangements of either chemistry is suitable.

 

[Samd]

Well said Lurkin. This has gone full crazy.

I could supply a rear 500w 26" kit for $250 delivered and a 36v 10ah for about the same. The guy asked where to buy a hammer to drive a simple nail and he got a range of responses on building his own pocket calculator to get to Mars.


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[=BicycleRider=]

Lol thanks for all the info, it's an interesting read.

That sounds like a good price for a battery (although it's sounding that I would need a larger one) if I ever get a 200w motor kit, but does shipping to Adelaide add a lot to the cost?

Ok so forget about nimh.

about 90kg weight + the weight of the road bike (gitane mach 1400) + any ebike kit of course.

I don't mind travelling at a fairly slow speed.
I saw this video and thought, I wouldn't mind going at this speed.
https://www.youtube.com/watch?v=zCx8nWC5Z64
Do you think it's realistic to expect to go this speed without peddling for 32kms with a 200w geared hub motor, how much faster could I go with a AFT 200w mid drive kit?

There's been many ppl saying forget about hub motors at 200w.
Getting a good middrive kit + battery + getting some bike shop to install it (since it sounds much more difficult) would probably cost getting up towards $1500 or more, there are new ebikes for around $2000 but then it's back to hub motors.

 

[cycleops612]

...I think you just need to understand - usually cheaper mid drive kits require maintenance and/or fiddling about to get the most out of them over time. The more expensive kits, like Bafang or AFT, tend to be more durable. Bafang is also significantly easier to install and is very tidy given the controller is part of the motor unit. I'm not sure if they have a 200w unit, but they certainly have a 250w unit (which I have) which is very discrete.

With over 13,000 documented kilometers in commuting to work and back... the Li-Ion pack is performing perfectly well.... there are pros and cons to either chemistry, either way. In the OP's case, a nice pack with a BMS for simple charging arrangements of either chemistry is suitable.

It would be better to say nothing than something as meaningless.

You could be using a heavy 20ah battery for a 10ah job. Hardly relevant,is it?

 

[cycleops612]

Its interesting to look at efficiency charts.

They reveal the best rpm is in the upper ranges (they seem to max out just below 3k rpm?).

On my sample mid-drive (no tacho), there are audible clues to high revs, rarely heard on a single speed, (similarly) geared hub.

To me, and logically, this means hubs rarely operate efficiently.

 

[cycleops612]

Are there any ni-mh ebike batteries available (ie. using d cells), ready made as packs with controllers? I read that some electric cars are still using them at over 90% percent after 100,000kms. How long would a lifepo4 battery last?

I built my first battery pack using NiMh D cells. I'd recommend against it. It was fine up to about 5km/h on the flats. The second you hit a hill, or needed more power to go faster, the voltage sagged and hit low voltage cutoff, resulting in a jerking forward movement. In theory, a much, much, much bigger pack might have solved this issue, but a pack of RC LiPos at half the size got me going to 40km/h, sagging only to high 30s up mild hills.

NiMh have terrible cycle life - around about 500 full discharges, or 800 for special "long life" NiMh. They fare a lot better when they have very low depth of discharges - such as in hybrid electric cars. The early hybrids basically only helped you accelerate - they wouldn't drive the car on its own. So you might only take 10% of the battery's rated capacity to start the car moving, then the petrol motor takes over and every downhill and brake you come across charges the battery up. In other words, in a hybrid, the battery is just a way to buffer momentum, (Stores energy from braking - uses it to start moving again) it doesn't "really" drive the car.

The 10% loss (and I'm skeptical it's actually that low) would have been almost entirely shelf life loss, not cycle life loss. So they were good for hybrid electric cars - can you name one fully electric car or plugin hybrid using them? Nope, because unless it's home made, there isn't one. There's a good reason for that - if you actually drove the car primarily by the battery, NiMh would be dead within a year. Likewise, NiMh will be a very poor choice for electric bikes, because you want to use the battery to actually drive the bike, not just buffer energy.

If you want long life and actually use the battery LiFePo4 will be the way to go. Choose a battery that can deliver around 3 times your peak draw and twice your required range, and the battery will last you at least 10 years. LiFePo4 has about 3000 cycle life to 80%:

Correct. Hear hear.

"can you name one fully electric car or plugin hybrid using them? Nope, because unless it's home made, there isn't one. There's a good reason for that - if you actually drove the car primarily by the battery, NiMh would be dead within a year. "

Well - Tesla, which is one reason they suck (another is the absurd concept of a rubber burning ev). Skeptical about 1 year lifespan, but thats cos nobody drives till remotely empty, as per your reasoning re 18650 li-mn longevity in hybrids- only the top 40% is ever used normally.

Ask any tesla driver about battery sag. They lose their zip fast, despite hundreds of kilos of 50gm batteries.

 

[cycleops612]

As I have said, a pedal optional approach is good in theory. For me its mainly for shifting loads when pedaling isnt possible.

In practice, as others have said, its not as tiring as it sounds when motor input considered. The same effort as a leisurely stroll, in the right gear, makes a big difference on a bike like yours.

Speaking of which, I have little luck with both motor and pedal gearing both being optimal on a mid -drive. Maybe its just me.

Bears thinking on, that the hassle of installing, must be repeated if you ever switch the makings to another bike, a bonus for simple front hub installs - easily transferable to a same wheel size bike..

 

[cycleops612]

fyi, from elsewhere on ES

"if you are after an E-bike which you will still be an active participant but want some relief from headwinds and hills at a pace that's higher than on your best day with pedaling only, and with less exertion, then the choice of bike IS important. For example, I presently have 3 E-Bikes; a flatbar road bike, a trekking bike and a (moped-like) cruiser. For one particular 31 mile loop I ride for the same average trip speed of 18 mph pedaling with normal effort (a bit less on the cruiser) I will typically use 7.5Wh/mi, 10Wh/mi and 13.5Wh/mi for each of those respective bikes.

If what you are building is essentially a moped that you drive at higher than normal bike speeds then the number one factor is SPEED. Unless you're going to push the speed envelope you can pretty much forget about this motor or that controller, simply buy the system which delivers the speed you want and the battery which can sustain that power. Frankly unless you choose a motor wound way too fast for your needs the power consumption is going to be very similar. In this instance aerodynamics will be the primary route to lowering power consumption."

 

[=BicycleRider=]

I would like to make motorised road bike that will go at average bicycle speed for casual riding but without having to pedal. That's not to say I wouldn't pedal always, sometimes I would pedal but I would like to have an options to go from a-b without pedalling sometimes as a novelty at least, except up hills where the motor couldn't power the bike on it's own. Ie. I don't want a motorised bike that requires pedalling to move.

I would be going on bicycle tracks so I can't zoom around at a speed where pedestrians would not be happy.
I don't need to get anywhere in a hurry so I don't mind if I'm not going particularly fast.

It may not be possible. I kind of think If it is required to pedal maybe I'll just get a better gear cog and not worry about adding a motor.

 

[MadRhino]

If I had to limit myself to 200w I would definitely get a mid drive setup and probably with a sram dual drive setup so that you can have the full range of gears for hills etc.

+1

A hub powered 200w is ridiculous. At least with a mid drive you can have the torque even at low power.

 

[cycleops612]

I would like to make motorised road bike that will go at average bicycle speed for casual riding but without having to pedal. That's not to say I wouldn't pedal always, sometimes I would pedal but I would like to be able to go from a-b without pedalling sometimes, except up hills where the motor couldn't power the bike on it's own. Ie. I don't want a motorised bike that requires pedalling to move.

I would be going on bicycle tracks so I can't zoom around at a speed where pedestrians would not be happy.
I don't need to get anywhere in a hurry so I don't mind if I'm not going particularly fast.

What type of efficiency would you expect with a planetary geared hub vs a mid-drive on the flats, no pedalling on the same road bike?

It may not be possible. I kind of think If it is required to pedal maybe I'll just get a better gear cog and not worry about adding a motor.

well done, quite a wise approach for a noob.

OK, well the crux of the matter w/ a hub is that u have 1 gear, so choose it carefully.

aim for the best rpm range at the most used (most power consuming) speed range.

dont quote me, but its common to have options when ordering hub motors, especially given the effect of different wheel diameters. It matters a lot whether the motor is on 26" or 28" wheels e.g. (w/ a wheel & motor kit, u know its correct, not for a bare hub motor).

Personally here in sydney, i would err on the lower geared/rpm option side - best for gaining momentum and getting to 25kph at close to max rpm.

I find the ability to do crawl speed in busy car/pedestrian ways on throttle only, a boon, so much better than compulsory pedaling on top of other complications.

as others have said, realistically, we are talking 250w & being legal to all intents (i heard same as u, 200w if has throttle only mode, 250w pedal assist mode only (seems absurd as can set for max assist on token pedaling, a sham for the cops)).

On a roadbike like yours, if u r not too heavy, thats a bit like having 3 pretty fit blokes helping by steady pedaling, at the cost of about 3kg each in battery & motor, probably less (geared 200/250w hubs can be very light i think).

 

[cycleops612]

If I had to limit myself to 200w I would definitely get a mid drive setup and probably with a sram dual drive setup so that you can have the full range of gears for hills etc.

+1

A hub powered 200w is ridiculous. At least with a mid drive you can have the torque even at low power.

maybe not.

its a sub 9kg bike w/ drop bars & we dont know what he weighs.

in still air on the flat, it only takes 100w to do 25kph on these bikes, 200w w/ good aerodyamics, ~35kph.

 

[emco5]

If I had to limit myself to 200w I would definitely get a mid drive setup and probably with a sram dual drive setup so that you can have the full range of gears for hills etc.

+1

A hub powered 200w is ridiculous. At least with a mid drive you can have the torque even at low power.

This is the reality I've experienced.

 

[Samd]

I'm just reading the feedback here and shaking my head.
Cycleops are you trolling? You're all over the shop. Its like you're actually trying to pull the thread off topic?!

Unless you can straight up quote things like watthours per km of hubs versus middrive for the OP's local terrain I think you're just bewildering the guy.

 

[Lurkin]

Go and ride a couple of ebikes to get a better understanding of what you will end up with. Even finished bikes will give you a better idea. Most shops will allow test rides, I was surprised to find 250w was sufficient for a road style bike with a bit of pedaling and a bit of help. Again, if you find a bosch middrive it will give you an idea of what its like to use a middrive.

This concept of using fixed gears is just rubbish. Its a choice used for higher power bikes because it simplifies the build and gears aren't required anymore anyway. Both middrives and hubs (depending on which you get) will allow you to retain your gears..... trick is finding one ideal that will take the current cassette or freewheel you have as to getting the right hub.

Perhaps I've missed it, but I'm still wondering whereabouts you are? We can then help you to get assistance closer to home.

 

[=BicycleRider=]

If I had to limit myself to 200w I would definitely get a mid drive setup and probably with a sram dual drive setup so that you can have the full range of gears for hills etc.

+1

A hub powered 200w is ridiculous. At least with a mid drive you can have the torque even at low power.

maybe not.

its a sub 9kg bike w/ drop bars & we dont know what he weighs.

in still air on the flat, it only takes 100w to do 25kph on these bikes, 200w w/ good aerodyamics, ~35kph.

90kg rider.

If those are the sort of speeds I could go without pedalling I'd be totally happy, but many are saying with a 200w geared hub I'd be lucky to move at all without pedalling. I kind of think I'd either like to pedal properly (no motor) or not have to pedal at all (with a motor) except up hills and starting.
So I'd like something where I can coast without pedalling most of the time.
Also I can't even get a 250w pedal assist unless it conforms to a 'long number' certification. So that rules out most of the kits anyway.

Yes drop bars, I'd be looking to get the thumb throttle so I don't have to change the handle bars to flat types. Although in the full drop mode I can't really see where I'm going and still be comfortable so I don't use it much.

 

[cycleops612]

90kg rider.

If those are the sort of speeds I could go without pedalling I'd be totally happy, but many are saying with a 200w geared hub I'd be lucky to move at all without pedalling. I kind of think I'd either like to pedal properly (no motor) or not have to pedal at all (with a motor) except up hills and starting.
So I'd like something where I can coast without pedalling most of the time.
Also I can't even get a 250w pedal assist unless it conforms to a 'long number' certification. So that rules out most of the kits anyway.

Yes drop bars, I'd be looking to get the thumb throttle


(CORRECT methinks, positioned so can use in both positions)

so I don't have to change the handle bars to flat types. Although in the full drop mode I can't really see where I'm going and still be comfortable so I don't use it much.[/quote]

u sound a sensible bloke & i guess its a bit fun for you. actually buying spoils the fun

What these guys dont get is its a racing bike. Bike will weigh ~9kg, motor 1.6kg (light would seem good given your ~frail front forks , the cute motors seem well regarded - mid drive would be at least 2kg heavier mthinks), battery 4kg (generous ~360wh (36v 10ah e.g) lifepo4). it has 120psi racing tires and drop bars. I prefer my advice to apply to a more real 250w.

so what u have is identical your existing bike, plus 5.5kg, AND 3 hard working blokes helping you pedal, untiringly (a fit labourer puts out 75watts average over 8 hour days).

90kg is not small I have to say. Its quite a big ask of the bike and power. A gvm of 105kg sounds within the bikes limits, but just. Still, if u r happy now with it, it should be fine.

I have been in a similar situation (a petrol motorised bike with no torque), and i found i stayed with the bike in low gear, and only pedaled in the steepest places

you have to spend money on a good battery, no avoiding it. Not much change from $400 for a 10ah lifepo4 36v from china. 48v may not be much more, but 10 ah is kinda overkill in weight and power.

fyi

https://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&cad=rja&uact=8&ved=0ahUKEwic4rqC7Y7OAhWIHZQKHZF8AOkQtwIINTAD&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D_r9efuGo_50&usg=AFQjCNGQnLl3mGFbSO3lqXzpqOqJYJwQQg&sig2=lyLdjByVA7dKahfiqCO0sQ

it seems to max out (which is close to its most efficient rpm) at 33kph and have an overhead of 20watts in the mechanism at no load (but a wobbly wheel).

As a plan B, am pretty sure any 200/250w motor could easily be configured for 350w if unhappy w/ 250w. Its all to do with the controller. 48v would be ideal, but 36v is ok too.
What they are factory set to and what they are able to do, is often very different. The main issue is having a battery that can supply those watts, sustained.

Controllers are set to have a max output to the motor, hence the power rating of the motor.

just to be sure, u do realise, bare hub motors can be ordered with optional "gearing". clearly a 24" wheel is very different from a 28" wheel. You may have some discretion in choosing slightly higher or lower gearing, apart from the dictates of wheel size.

look, i love mid drives. definitely the best. spend the A$1800 for a factory 24 gear mid-drive and i am sure u wont regret it. but for a 30k commute on good pavement, testing the water cheaply, yet a damn good ongoing solution also - given wind is the main enemy above 25kph (it would take a lot of power to equal the effect of drop bars above 25kph) and those bigger wheels for smoothing bumps....

but if, per the question, u use that bike, its over the top for the bike - its a silk purse made of a sows ear.

for stealth, i would choose dull over shiny finish hub.

I felt the same about drop bars, but i got to like them. They are really just flat bars with a heads down turbo option in wind (when its pointless pedaling, just steer and glance up).

front/rear - meh, front is certainly simple. Its not beyond the bounds, to have a spare bike, ready to go if u have bike problems on your main steed.

swapping the bits to a reserve bike would be under an hour if rehearsed. if my living depended on it, i would consider a backup, same as folks need loaners when the car is at the shop. No fix is stressfully absolutely urgent. even a bent frame wont ground you. parts can take a week, even locally in oz.

A downside for front hubs to slack old urban me, is my breakdown plan is the back seat of a cab and "home james". a simple qik release front wheel means it fits in more cabs, easier. dunno, but a front hub motor makes this a bit harder, need a spanner for starters?.

I would seriously consider the xiongda 2 speed hub motors. perfect. best of both worlds, a low & hi gear in the hub itself. its 3.5kg & u have to check axle lengths suit your forks, but your rim brake setup should be fine. its well worth an extra $100 for the motor, & i hear the 48v has a way better controller.