sethimus
😠 Temu Gary 😠
i see a 3-4cm low hanging problem with this solution. NEXTThe E2 motor showcased last year (still not released) looks to be quite similar the newer motors:
GOBAO ECVT EMTB Mid-Drive Motor
a
- Thread starter slickrock
- Start date
sethimus
😠 Temu Gary 😠
awesome, even more buttons on the handlebar. we clearly don't have enough of them already
sethimus
😠 Temu Gary 😠
yes, we all saw the forbidden and mondraker cargo bike prototypes. clearly it's intended use. srsly, are you for real? do you have eyes and are you able to use them? are you so full of it so you need to throw shade on everything not being a bosch motor because that's what you chose now?
First of all, it's a guess, just like all of us are guessing, because it's an enthusiasts forum, and that's what we do. So calm down.
Secondly, and importantly: I'm just more committed to 'bicycling' being a distinct sport from 'e-motorcycles'. Avinox has already chosen to blow the lid off of the Class 1 bicycling limits imposed by the industry. Now we are going to have AI controlled cadence, auto shifting, motor gearbox units. Will they be faster and perform better? Yah, probably. But we are getting pretty far away from the manual experience of riding a bicycle at that point with some 'climbing assistance'. Yah know, pedaling, flipping the thing over to adjust the manual parts, etc. It's just all a bit much to look in the mirror without smirking and claim to be 'riding a bicycle'.
You can't claim a Class 2+ e-bike is the 'best' Class 1 e-bike no more than a CRF450F can claim to be the best 250F.
I've said it before and I'll say it again: why do these have cranks at all? At this point it's just a bit of a silly way to pretend to be powering the thing. Think of the reduction in complexity, parts & weight if they simply had an electric motor and a throttle? The cranks are an inelegant throttle at best, or just decoration at worst. Like an EV car with a manual shift lever and clutch pedal that in reality does nothing at all besides stroke the ego of the driver. How long until they offer a drop in replacement motor that is just an electric motor with footpegs and a throttle that drops 2 kgs? That actually makes sense.
Last edited:
sethimus
😠 Temu Gary 😠
Diby2000
New Member
While I agree with both arguments here, They can also go both ways.
The same argument can be made about the first bicycles that had 2 wheels that where a similar size (not penny farthing). Or when suspension arrived, or when gears arrived! Its all progress. I admit there could be a line in the sand somewhere, and you are drawing yours here. This is not where everyone is drawing it though.
slickrock
Well-known member
- Thread starter
- #250
I've given this a fair amount of thought. IMO, the main distinction between e-motos and EMTBs really comes down to the throttle. It's throttle the disconnects you from power delivery, so in this way motos are similar to cars, unless your Fred Flintstone. With my first ebike (Leve 2nd gen), the motor belt like a straight amplification of my power at the pedals, and fooled my brain into thinking that I just got suddenly stronger. It did not feel foreign, or disconnected, but rather; it felt like an exciting extension of the MTB experience, where you provide the torque and cadence to power your bike along. A throttle would just kill this primary experience that comes with mountain biking. This is why I'm not that opposed to Class 3 systems, since you still have to pedal with cadence and torque to move the bike forward - you are still connected to the bike in a way that makes you more responsible for its power. Class 2 ebikes have throttles, and that to me draws a hard line against such bikes on MTB trails - you might be limited to 20mph, but you can go crazy with torque and power that can contribute to rider irresponsibility.
But then again, what distinguishes cars from motos, as the gap between the two is obviously huge, yet both have throttles and allow you to steer? With motos, your COG, weight and balance directly influences the operation and handling of the vessel and that is totally under your control. I'm teasing out this distinction because with EMTB, this is even more of distinction as you body weight is 3 times that of the bike rather than other way around. I see this as a strong secondary factor of the EMTB experience. Why am I calling this out? Because ECVT does not take this way from the riding experience any more that an e-bike motor can.
But there is a fear that ECVT is taking away the third experience factor: gear selection and control. With gear selection, you are the control system that regulates your own power delivery at the pedal, allowing you to balance torque and cadence for your own optimal delivery where the terrain requires either speed or torque to negotiate. EMTBs with all their power, have made this less critical as riders don't have trade torque for speed as much (the reason why 12 speeds are overkill), and so have a tendency to overtorque and damage their drivetrains. But this is the area where ECVTs have the greatest impact and change the riding experience. You still control the transmission yourself, but now you just have a lot more options. You get to choose the gear steps and ratio intervals in a why you could never customize before. When your just shuttling or fireroading to a destination, you can drop into a bunch any number of auto modes, that maximize efficiency or power delivery by allowing you to set preferences of cadence and torque. Safety systems could be introduced where you can set a max torque thresholds to save your chain or hub (to not depower the motor but rather reduce gear ratio you are in a the moment), not to mention the trails. Gabao even has auto-manual mode, which automatically shifts through the gear steps you configure, so it feels like auto mode in an MGU or vehicle automatic transmission, rather then feeling like a full CVT. So while ECVT can take over control system duties for gear changing, you get to choose just how much you want to relinquish, just like you get to choose how much human power you want to relinquish to a motor.
Diby2000
New Member
I believe you may have touched on my thinking here also @slickrock.
Yes the throttle is a big factor, but I think the weight is playing a huge factor for me. I think the weight of the system vs the weight of the rider, and the influence of the riders position is what makes it fun for me.
Yes the throttle is a big factor, but I think the weight is playing a huge factor for me. I think the weight of the system vs the weight of the rider, and the influence of the riders position is what makes it fun for me.
If all you want to do is "Go ride a Bike". Then go ride a bike. No one is stopping you. Not Gobao. Not us. But trying to tell people who want the most advanced EMTB, they shouldn't have it, because you don't feel it's in the spirit of true cycling, is absurd.
If the EMTB complies with pedal-assist regulations. Then it can be ridden anywhere a pedal-assist regulated EMTB is allowed. And there is no suggestion that the new Gobao ECVT won't comply. If you feel the cranks have become a throttle. That's your issue. No regulatory authority is remotely suggesting that cranks are in anyway defined a throttle.
So it's pretty simple. If you don't like the technology. Don't get it. But this continued droning that advances in EMTB technology, suddenly makes EMTBs a motorcycle is not supported by regulatory authorities. And it's their opinion that matters, not yours. Their definition of a Pedal Assisted Bicycle and a Motorcycle is very clear. Read your regulatory authority definitions, if you are unclear.
And lastly. The ECVT works as a fixed speed gearbox, if you turn all the electrics off. Your legs drive the planetary carrier. The planetary gears drive the ring gear. The ring gear drives the chainring. The chainring drives the chain. Then the chain drives your rear wheel. There is no virtual pedalling. You are directly driving the wheels, through gears, from your legs.
When the electrics are working. The electric motors act to add pedal assistance, by adding assistance to the ring gear, and rotate the sun gear, to vary gear ratio. That's it. It's still a mechanical gearbox. The fact you don't understand how it works. Doesn't suddenly make it a motorbike.
Last edited:
sethimus
😠 Temu Gary 😠
throttle bikes are only a thing in the usa, not allowed in europe. stop using your usa goggles all the time…
cycling/bike wise you are a tiny, irrelevant country with complicated ebike rules nobody else has.
Joecrow
Active member
Looks like a case of the pot calling the kettle black!
I'm interested what's everyone's thoughts on electrical efficiency for the e-CVTs.
My thought is that due the fact that it has two electric motors, the final output power(i.e. 1500W peak) will most probably be a sum from both motors, as otherwise the range would suffer a lot or we would need a bigger battery.
My example:
Motor A provides forward propulsion(the stronger one, i.e. 1200W peak). The usual power draw.
Motor B(the weaker one, i.e. 300W peak) constantly spins the planetary gearset. That is additional(constant) power draw as during Acceleration/Climbing: The control Motor B must spin rapidly in forward or reverse to dynamically "fake" lower or higher gear ratios. This causes the internal planet gears to spin at high speeds around the sun and ring gears.
What I would like to point out here is that the smaller Motor B will basically always work, even when you aren't actively accelerating or decelerating but just steady cruising Motor B will consume some electricity just to maintain your current "virtual gear" by being electricaly locked in position.
So take for the example eMTB type ride environment where there is a lot of constant acceleration and deceleration. The gear ratio control Motor B will have a lot of unstable work that is not optimal for energy consumption with an electric motor.
So my opinion is if we want similar efficiency that today's mid-drives have, the final output of the eCVT MG power will need to be a sum of both electric motors.
My thought is that due the fact that it has two electric motors, the final output power(i.e. 1500W peak) will most probably be a sum from both motors, as otherwise the range would suffer a lot or we would need a bigger battery.
My example:
Motor A provides forward propulsion(the stronger one, i.e. 1200W peak). The usual power draw.
Motor B(the weaker one, i.e. 300W peak) constantly spins the planetary gearset. That is additional(constant) power draw as during Acceleration/Climbing: The control Motor B must spin rapidly in forward or reverse to dynamically "fake" lower or higher gear ratios. This causes the internal planet gears to spin at high speeds around the sun and ring gears.
What I would like to point out here is that the smaller Motor B will basically always work, even when you aren't actively accelerating or decelerating but just steady cruising Motor B will consume some electricity just to maintain your current "virtual gear" by being electricaly locked in position.
So take for the example eMTB type ride environment where there is a lot of constant acceleration and deceleration. The gear ratio control Motor B will have a lot of unstable work that is not optimal for energy consumption with an electric motor.
So my opinion is if we want similar efficiency that today's mid-drives have, the final output of the eCVT MG power will need to be a sum of both electric motors.
Your theory is that less power will get to the wheel, but if we start with a sum of 1500 watts, there should be plenty left over, since for years we were riding with 750 watts, right?
Yes, I think power will be plenty enough. I am just speculating about how much energy will the secondary smaller motor consume as it will be basically working constantly in an emtb environment type of riding.
The only time this motor gets a somewhat break is when you/bike cruises at a constant pace/cadence smoothly, that's not the case on most emtb rides, and even then slight changes in cadence spin the motor again, and even holding the desired virtual gear ratio at a preferred cadence costs some energy if I am thinking correctly.
I'm really interested on how these units perform irl.
DirkWisely
Well-known member
My heart rate and sweat soaked shirt would argue that I'm not simply a passenger.
Who said you were? What an odd and irrelevant response.
It’s a big planet, and we’re all pretty small in the grand scheme of things. Every country has something unique to offer. As Ron Burgundy once said... wait, who said 'size isn't everything'? Either way, Switzerland might be smaller on a map, but its quality of life and diplomacy are huge.Looks like a case of the pot calling the kettle black!
slickrock
Well-known member
- Thread starter
- #261
Actually the gear-ratio motor (MG1) acts as both a motor or generator depending on overdrive or underdrive modes. I got Nano Banana to draw a diagram, which looks mostly correct except it didn't get the grade drawn correctly because it lacks a world model [Edit: text is correct in that the the sun gear drives MG1 but the illustration implies that it's connected to planetary gear, which is incorrect]:
In underdrive, the motor acts as generator, rotating in the opposite direction which allows the ring gear to move more readily without much rider pedal torque as well as the allow planetary carriage to spin faster, allowing the motor to main power motor (MG2) to rev faster (essentially downshifting both the crank and motor simultaneously). Crucially, the electricity generated with powers MG2 directly (as thin the diagram) or charges the battery, so energy is not lost. It's probably in this area where efficiency take a hit (generator-inverter-motor engergy transfer). But efficiencies are gained elsewhere in that the gear ratio can keep the motor and rider in a more optimal efficiency band all the time.
In overdrive, MG1 spins in the forward direction along with the ring gear, both contributing to power output along with the main MG2. So here, yes, both motors are drawing battery power to drive the bike forward, and slowing down pedal cadence to allow the rider to apply more power to the final drive at a lower torque along with the motor, now in a lower revving state to provide more power at a lower torque. In this state MG2 is reducing some of its duty because MG1 is driving the final drive as well, so power consumption from MG1 is compensated by less power draw from MG2.
So in the end, efficiencies may not be as bad as some think IRL.
Last edited:
There are some anomalies with that drawing. Like MG1 is driving one of the planet gears, rather than the sun gear.
I modified this drawing below.
1) The pedal cranks drive the planet carrier.
2) The planet carrier rotates the planetary gears between the ring gear and sun gear.
3) MG1 directly drives the sun gear.
4) MG2 is directly driving the ring gear.
5) The ring gear is directly driving the wheels
So if you are peddling. The speed at which the ring gear moves, is determined by the speed and direction of the sun gear, compared to the speed you are cranking the pedals.
As stated above. When the MG1 is being driven in the Fwd direction, MG1 is consuming power, and MG1 and the battery is driving the sun gear. When MG1 is being driven in the reverse direction, it is creating power, and MG1 is not driving the sun gear. The sun gear is driving MG1. So the cranks or MG2 are driving the sun gear.
So ........ MG2's power is always going to the ring gear, and hence the wheels, and some transfer to MG1 at low speeds, but MG1 will be driven in REV, and will act as a generator in this case, and not lose that energy. At higher speeds, all of MG2s power will go to the wheels, plus the power of MG1, being also driven FWD by the battery.
slickrock
Well-known member
- Thread starter
- #263
Yes, Nano got it wrong as MG1 drives the sun gear, the crank drives the ring gear, and the planetary carriage drives the final (though you could swap the ring gear and planetary carriage duties between crank and motor and get the same result). The point of the post was to address the efficiency of MG1, which I still intact conceptually.
Ok I see what you guys mean, basically a power split device, here is a nice emulator of the Toyota PSD(long press on the gearset icon opens controls). Just imagine the ICE is the bike crankset.
Toyota Prius Power Split Device : Free Download, Borrow, and Streaming : Internet Archive
Yes the regen would probably offset some of the energy consumption of the smaller motor B. We will just have to wait and see what it will be irl.
Toyota Prius Power Split Device : Free Download, Borrow, and Streaming : Internet Archive
Yes the regen would probably offset some of the energy consumption of the smaller motor B. We will just have to wait and see what it will be irl.
DirkWisely
Well-known member
"I've said it before and I'll say it again: why do these have cranks at all? At this point it's just a bit of a silly way to pretend to be powering the thing. "
So you just forgot what you typed?
Similar Threads
-
Pinion pulls the plug on EMTB motors [mod edit- Fake News]- Started by BikeBert
- Replies: 19
-
Current Avinox MG Prototype Bikes Don't Support Battery Regen- Started by slickrock
- Replies: 94
-
-
-
