Excellent tutorial. I had to read and study lots of detailed books about this subject to understand the differences and how they related to each other. In less than 11 minutes, you've perfectly, clearly and concisely described and explained what I had to learn the long and hard way. I wish this video had been around when I was learning this stuff.... well done!
I have waded through all of the amateur videos, the informed videos and the well informed videos and I have gleaned a little knowledge from them all. Some, more than others ( like testing + and - wires at both ends before frying a new £200 battery) . But now I feel I have arrived at Ebike University. Greatest Ebike channel of them all IMO. Thank you from Ireland and keep up educating the masses.
Well, for those like me, haha, I was unable after welding batteries purchasing BMS's to be able to understand exactly how that final S series was counted. It finally hit me after going back to basics, watching these very easy to follow builds. That, the final S count that I was always missing was: the very first battery that has both the positive and negative going to it, even though it wasn't exactly making an S series connection, was the very last counted Series battery. Maybe very easy for everyone else, but had been banging my head around that for months. So, Thank you so very much for helping me stop feeling so stupid and knowing for sure I knew how to correctly look for and buy the correct BMS for the battery builds I was doing.
That's not correct. In a series connected set, positive is on one end, negative is on the other. the path of electricity has to travel through each battery one after another.
Great video... Yes, torque ratio to watts is the most important measure. It's how the bike will perform off the line and up hills. Basically how the bike will 'feel' to the rider. - Sluggish vs muscle.
last but not least wheel diameter (in case of hub motors which put less strain/wear on the mechanical drive train) plays into how efficiently those Newton meters actually propell the vehicle forward. The smaller the wheel the sooner rotation and efficient rpm can be achieved. I have a rickshaw which often amounts to a total system weight of 600+kg, but with a geared hub motor in my 16 inch front wheel I'm getting the most when starting the race at the green light at Octoberfest outrunning my colleagues with 200kg less who are running the same 250W nominal system on slimmer tires but with 26 inch diameter. (it might also have to do with me being the GOAT in rickshaw racing but don't tell them that ; )
The Ebike community seems to love the “I could climb a hill” selling point, but I’m over here in Florida getting reminded every couple videos that hills exist. Cheers.
WOW, Thanks a lot! As a retired electrician, Your explanation clicked 100%. Something else I see is batteries being rated in watts with no reference to amp hours. Often digging for other sources, I find the '360 watt' battery is 48V and doing the math get 7.5AH which is kinda small... Just liked/subscribed and bookmarking this video!
im unsure tbh 360 watt would refer to the motor power the battery should be rated in AH however what I think might be going on here is for reasons I don't know they could be rating the battery in watts referring to the motor its suitable for for example calling a 32 volt battery a 250-320w battery because that's what you mostly use for those and calling a 42v battery a 500-700 watt battery with a 72v battery being a 1000+ watt battery for reference my bike is specced as follows 350w motor 32v battery 11.5ah battery if we wanna rate my battery in W/h as opposed to A/h my battery is 368W/h in capacity but generally when it comes to ebikes if its talking amps there referring to the AH of the battery if there talking watts its almost always the rating for the motor and volts being what the battery is delivering there's a whole thing for over voting the motors to get a lil extra performance as well as going for higher voltage batterys to reduce charge times as all chargers are limited by there amp ratings so upping the voltage is a easy way to get more watt hours into the battery faster without pushing more amps I've even seen some ellect to install 72v batteries and regulate them down to 32 to benefit from having a smaller battery and faster charge times but still having the range a larger lower volt battery gives them
@@Sarge92 That's a lot to wrap one's head around... I note that 'A' also refers to controller ratings. We could really confuse things saying my T42 is only 1.1 KVA peak... If a controller is rated up to 72V and being used on a 48V hub, what's the risk of going in series with a 12V agm with the 48V li-ion to get 60V operating voltage?
The battery rating in Wh is more honest than giving A*h, as the Wh charge actually defines the amount of energy stored in the battery. A good comparison factor is the battery consumption in Wh/km or Wh/mi. Giving only Ah rating (without the voltage) is deceitful. Giving Wh is honest. Big brands always give the battery rating in Wh as not to deceive the customer.
@@StefanMikulski You say "Giving only Ah rating (without the voltage) is deceitful".... I submit, So is Wh - (without the voltage). 360WH could be 36V 10AH or 48V 7.5AH... Speed comes from voltage. VA's or Watts is actually 'power' giving an idea of how long a load will run. Or, in the case of a motor, it's hp rating since 742W=1hp.
@@johnw65 speed comes from voltage? How comes my 36V Specialized Turbo Vado 6.0 can get at 45 km/h (28 mph) while a derestricted 48 V Specialized Turbo Vado SL can only get at 34 km/h (21 mph)? No, the voltage is irrelevant here. Speed comes from the motor power, which is mechanical 520 W peak in the former and mechanical 240 W in the latter. The speed also affects the battery energy draw. That's why the former battery is 604 Wh (36 V 16.7 Ah) and the latter is 320 Wh (48V 6.6 Ah).
I know most are watching this for the knowledge of the ratings, but this has actually taught me a lot about battery building. A concept I never understood was the max wattage rating, and now I understand, its just the max current the battery will put out multiplied by voltage.
Thanks, here in the UK, as you say we have 250w continuous, I am very happy for the manufacturers to allow us to overamp their motors for more power, they know we will not burn them out at say 750 watts for a reasonable time. I may be wrong, but I think the Bafang 250, and 350 are the same motor but different controllers to allow more power. It is a way of giving us a good product and stay within regs, a point you made well.
only danger with overamping would be being involved in an accident having your bike looked at by a sworn expert making you liable for operating an illegal motor vehicle. The bike squads in Germany are no fools and are regularly making examples of obviously overpowered "250W"ebikes (which could be legal if they had a moped plate and all the other items required for fast ebikes)
@@velotillthis is why the laws are a bit dumb. What should really happen is there should be a law on use of peak power to allow fast starts and uphill runs tied to the amount of torque provided by the rider. Fast starts for 10 seconds up to 10 kmph on flats (until you pedal past it) and during cornering to get you out of trouble and when hitting an incline allowing the peak power to stay on for as long as you provide enough torque to keep up to the maximum speed llmit of 25 kmph.
1:27 Yep, a big 10 ton trolleybus has an electric motor rated at 100kW. That low! But that is the continuous power. And trust me, during acceleration from standstill, the motor drives much more current than 175A (runs at 600V). That is the reason why there are components limiting maximum current, as the motor would happily take all it can get. And yet, differentials and axle reductions wear out sooner on trolleybuses than on buses. And if the regulator malfunctions, a trolleybus can easily do a burn-out on a dry paved street. Of course, do it three dimes and you can replace the whole axle, if the CV joints on the shaft between the motor and differential do not break sooner. Or you blow the circuit breaker in the trolleybus (should break around 380A, but that is only theoretical) or you trip the breaker in the electrical substation feeding the section where you draw your power from. If you had no protection circuits and a very powerful source, applying 600V directly into the motor would most likely result in lightnings flying out of it and ripping it from the frame of the trolleybus, destroying everything between it and the wheels of the driven axle(s).
This is my first time to one of your videos. I’m subscribed!! I understood everything while you talked, but need to listen a couple more times to really understand. I’m shopping for my first ebike. It isn’t easy. But, you have helped a lot!! Thank you! I’m going back to listen to your other videos! I needed a white board with your numbers on it. Visual learner, here. Good job!
Thanks for explaining some of these terms as they apply to the ebike market place. I just recieved my T-1 replacement and didn't understand why the new motor was labeled 250w. Now I do.
You forgot to mention that a particular motor designed to go with a specific voltage will not put out more power just by changing the controller, the voltage will have to go up, which means changing the battery as well as the controller. Ohm's law hasn't changed!
That’s totally wrong. Not only have I swapped out batteries from 48V to 52V, I’ve swapped controllers after switching to 52 and my CLyte 3540 (rated at 1000W) and upping my controller from 26A continuous to 35 continuous definitely puts out more power. There are literally thousands of examples of this to choose from, not just my experience of riding my DIY ebike 30,000 miles. Yes, it is more susceptible to heat (loss), but it’s certainly not all lost to heat. I assume you don’t have an ebike. Ebikes.ca has a simple motor calculator and you can input values for many types of motor and controller combinations and see the data yourself.
What you call power is the torque which is a function of electric current not voltage. Varying the voltage would vary the speed. Amps = Torque (more powerful), volts = speed (faster)
In UK (and EU) the max continuous power output is 250W for an electrically assisted bicycle but if you want a higher output bike then that is classed as an electrical moped i.e. a motorbike driven by a motor and pedals. The issue with this comes from the requirement that to be an electrical moped it needs to be type approved or to have an 'Individual Vehicle Approval' to show that it complies with UK/EU vehicle build laws and that it will also need to be licenced, taxed and insured for a minimum third party cover. The rider must also wear an approved i.e. motorcycle crash helmet and preferably protective clothing and although not mandatory, the police might pull you over for inappropriate wear if you had classic Lycra shorts and top on.
Thanks for your clear explanation of ebike power. I’ve been researching the subject for a couple of weeks, and yours is the best, most straight forward explanation yet. Again, thanks. Please keep up the good work.
Very good explanation of "power". Keeping it simple using VA can help those not familiar with end to end input to output and the various losses along the way. Something to consider is the fully charged battery versus the nearly discharged battery. Power is greatest when the battery is fully charged and is minimal with a mostly discharged battery.
First class and full marks - easily one of the best explanatories I've ever seen. Thank you very much and happy travels (remember: "No helmet? NO WAY!").
Excellent information, I’ve been using the torque number and 750 W as my comparison point since my neighborhood is hilly. My driveway has 7+ feet rise of elevation 😂
This is my random comment, The Ultimate Do It Yourself Ebike Guide. Thank you for this video, it explained a few things I was trying to figure out. 500W 32kmh/20mph limit where I live.
Sooo.. My Super73 SG1 (EU version of the S1), has a nominal rating of 250W, which is the maximum allowed wattage in Europe. The motor also says 250W etc. However, having a 48V battery, and the controller's current is rated at 10A with a maximum current of 20A, it's very obvious that this is a 500W motor with a peak at almost 1000W, which is the same as the original American S1. The European version is electronically limited though, but I've unlocked it by plugging the US throttle in, and I'll just say that if this is "250W", then it's the most powerful 250W motor in existence 🤣 Ain't complaining though!
You talked about this several years ago (I think too, it’s also in your book) good to hear again. I think you put it better here. It’s not as text book more layman’s terms I guess. Same but more relaxed and I think easier to understand. Good to hear again very important. And yes we do benefit if we know how to take advantage. That we can (w/aftermarket controllers) put together a bike that we love to take for a ride!
Thank you so very much I have known watch amps and volts since high school but the Newton meters now I have something I can really use thank you so much.
I love how continuous and peak power has an excellent explanation to them, telling you exactly what they're about, then you get to nominal power and it's basically 'this means nothing. it could be true, it could be false, and even if it is true you won't know "how true" the rating is unless you test it.' It is pretty hilarious and i can see where the frustration can stem from that.
this channel is quickly becoming one of my favorite youtube channels, this video is extremely informative, i dont yet have an ebike but my father and i are both interested in getting an ebike so we have been trying to soak up as much info as we can before purchasing our first ebikes, thanks for the all the informative videos you put out there :)
@@acehighdan sorry to hear that. Hopefully parts will become cheaper in coming months. One price of advice I would give for those just starting out is that if you pick up a Liitokala hoverboard battery from AliExpress for $25 you have got a sufficient battery to get you started with a 36v kit. If you could do a shift extra each week at work, you may be able to save up the $150 needed for the motor and controller in a short time Or wash cars or Windows for money. Or now lawns
I have been watching your videos for a long time and thanks for your information I learned a lot throughout time!!! I became scooter technician and a lot of information came of watching your videos!!! Thank you my brother as always! Great content!!!
That is going to be my winter project, I have been ordering LiFePo4 32700 batteries, to make a 16s 3p battery pack. Probably will go with a Daly BMS. I'm also curious what welder you got, and what thickness of nickel you plan on using
Here are results of that tab welder. Now im not an expert on welding but maybe someone can answer my question on it. Again this is a first time thing for me and maybe I bought a bad welder but if anyone know's more about how good or bad I did id love to know. Thanks again! ruclips.net/video/LERZ14QSksE/видео.html
During my studies for electrical engineering the lecturers told me that the advertised motor power is usually mechanical. the mechanical power is calculated by multiplying angular velocity and torque. Mechanical power is the power you get from motor. The power you were talking about was electrical or the input power.
The power rating system reminds me of the Japanese gentleman agreement between the Toyota supra and Nissan GTR when it comes to horsepower making in the same
Yes & Motors have torque & power curve. A hub motor may find life hard turning slowly on a steep hill & heat up fast, but a mid drive is geared crank speed, so should be in the middle of its design range hill or flat. & its also important to remember the gearing factor difference between Torque for a hub motor & a geared mid drive.
Very interesting information as always. I’m so glad you mentioned Newton meters as that’s how I judge the power of a motor. Seems like your bicycle clock like mine needs new batteries.
The basic direct drive hub motors like violamart have the same direct drive hub motor but the controller varies, it could be sold as 500W, 750W, 1000W, 1500W or 2000W with only the controller varying and the hub motor remaining the same. How is that motor rated. Also if you buy lets say a 1000W version and use it with the minimum size battery it will accept about 48V at 12Ah in the road legal mode it is 250W approx (more like 300W) but if you disconnect the wire you get a 50% boost to 450W approx but the battery can peak at about 960W (20A) output for about 60-90 seconds or about 700W in road legal mode. It's confusing as clearly the battery BMS and controller and motor are not at the same level. I guess the BMS dictates the actual power the motor can receive, the controller could handle more and the motor itself could handle much more. I'm not sure what the nominal or continous rating of such a hub motor is but I guess at least 1000W. I've heard of Bosch motors easily peaking over 700W despite being road legal but many would view the Bosch as road legal and the home kits as not and its one factor why people pay more for a Bosch bike as they worry about the legal implications of a crash with a kit motor hub. The law seems a mess. However here in the UK I don't think anyone has been prosecuted with a home kit and you wonder if the police just check that it doesn't assist beyond 15.5mph because its the only simple test they can do.
I have the 1000 watt voilamart hub motor, and it peaks around 1200 watts according to the screen. I bought the voilamart 1500 watt controller instead of trying to play with the internal shunts on the stock controller. It has been sitting on my work bench for over a month now, cause I wasn't sure if the hub motor would take it or not (wire size)... I wish Micah would respond to comments... I think I should be ok as long as I don't full throttle it, I just want some extra torque on take off
@@chrisnmichelle0218 Can I ask what battery you are using both volts and amp hours plus if you know what peak current it can deliver for how long? Which cells are you using if you configured the battery yourself? I have the yosepower 48V 12.5Ah hailong case battery pack which uses Samsung 2500mAh cells which allows a peak current of 20A for 60-90 seconds. As stated above pretty much the minimum the 48V 1000W motor will accept which I think is stated as 48V 11.5Ah minimum battery. I use it in the restricted street legal mode partly due to legality but also because the battery is such a low capacity for this motor.
@@bonzobanana1 16s 1p 48v 20ah lifepo4 BTR power battery (www.ebay.com/itm/282691708617) it is made with lifepo4 pouches, not cells. 50A continuous discharge, 100A max discharge. The battery is great, but it weighs almost 20 lbs and I have to mount it on a rack behind the seat which throws the weight balance off. I have been buying 32700 liitokala lifepo4 (m.aliexpress.com/item/4000073953939.html?pid=808_0000_0109&spm=a2g0n.search-amp.list.4000073953939&aff_trace_key=0f27108c4dae4f51866478090c8a265e-1598364242794-04812-UneMJZVf&aff_platform=msite&m_page_id=6236amp-8afh0fKpUqPr1GppmYPgnw1598364304447&browser_id=3d094fe9d33b4a2fba89779d51150c11&is_c=N) 3.2v 7ah batteries, with continuous discharge rating of 35A per cell. I plan on building a 16s 3p battery with the 32700 batteries, and a 50 amp bms for it. That would get me 51.2v 21ah battery with a continuous output of 50 amps limited by the bms, I plan on using a bms made by Daly, as they have great ratings. I'm kinda sold on lifepo4 batteries because they have a much longer lifespan of 3000 charges (I don't ever drain my batteries dry) and just being a safer and more stable composition where I don't have to worry about thermal runaway if I push the batteries really hard.
thanks, awesome video, very thoughtful and very nice of you how you explained how companies don’t actually lie but in fact what they do is to comply to the estates regulations and just create misconceptions of legit information of the tag/specs readings. Just can’t appreciate enough bro. have an awesome life. 👌👍👍
Also, a couple other things: European "continuous rated power" isn't continuous power! It is, to quote Regulation EU No 168/2013 Article 3(35): "‘maximum continuous rated power’ means the maximum thirty minutes power at the output shaft of an electric engine as set out in UNECE regulation No 85" And "maximum thirty minutes power" from that UNECE regulation: ""Maximum 30 minutes power" means the maximum net power of an electric drive train at DC voltage as defined in paragraph 5.3.1. of this Regulation, which a drive train can deliver over a period of 30 minutes as an average" Additionally, there's test procedures in that regulation that define it better, and where the loophole comes in - the power level must be the manufacturer's best estimate of maximum 30 minutes power, and the RPM must be in a speed range that allows greater than 90% of maximum peak power (which is determined in a separate test). If the manufacturer estimates too high, of course, it'll fail the test and they'll have to re-run it, but if they estimate too low, it'll pass. The US regulations not actually saying what power rating standard is in use make me think the safest bet is to assume the more (but not the most) restrictive interpretation - 750 W peak output power. I don't think any of the vehicle regulations in the US are actually using continuous power (whether over a specific time or indefinitely), but then the US doesn't usually restrict power output, either, outside of e-bikes and state laws restricting what can be used as a moped/motorized bicycle/scooter without a motorcycle license. Then, there's one problem with your methodology of determining peak power: efficiency. So, just because you've got 36 V, 15 A coming from your battery doesn't mean you have 540 W coming out of your motor. If your motor/inverter system is 85% efficient at peak power, you've got 459 W coming out of the motor (and 81 watts of heat that your controller and your motor need to dissipate), and that's your real peak power. (There's additional drivetrain efficiency considerations downstream if you have a mid-drive, but my understanding is that power regulations care about motor output, not wheel output.)
US goes for Continuous power. Rating the motor by peak, is incorrect for it's performance. Peak is the RPM and torque a motor goes through before it reaches it's end power point, then tapers down in power. So once it's up to speed, it's not at it's peak power anymore. Same as Gas cars,etc. If they ruled for Peak, Electric/Gas devices would suck. It's like saying, This car can only have 500rpm and such % of torque. You realize how SLOW that car would be to get up to speed? It'd be like a snail trying to get up to 40mph, in 20mins. So if a state has a rule of power of a 750watt motor as limited. That is continuous power rule. Not Peak. The motor can have 2x more Peak, because that start power the motor goes through. Again like a gas car,etc. It's the start of the motors run to get whatever it's pulling/pushing up. Then it lowers down to it's continuous power performance which runs at a stable set.
@@TheAvkdutch You're a great example of how dumb the world is. "Will listen to this stupid twit on this epic website that doesn't know crap, But not to someone who knows the truth on a comment." You should've just never commented, Cause you just made yourself look like a fool and just showed everyone else like you how dumb they now can see themselves.
Hi I have just placed an order with amazon for your book on lithium battery building , I have had really good / the best information on e bikes from your RUclips post thank once again
Hey, just a heads up. Several of your links to Aliexpress are dead. The 18650 cells link goes to a charger. The 1000 watt complete kit is dead. There are others that are dead, just some housecleaning to do with your links. Thanks for the videos! I'm a fan.
You should run a non profit association that lays out a spread sheet of the bikes and all their true non biased ratings. …you know the truth about these bikes. Well done video!
Auto manufacturers underrate their motors too. The 06 Chevy cobalt SS LJS supercharged 2.0l motor is advertised as producing 215 crank hp. I assume this if to keep insurance rates low, because they routinely dyno at 235hp at the wheels before any mods. I'm happy to get an underrated motor in my e-bike because excellent reviewers, such as yourself, make head to head comparisons revealing the "truth in advertising" very quickly.
Pretty good. I find it helpful though to go to the next stage as what we are trying to do is compare the human power at the back wheel compared to the assistance power at the back wheel. And for that we need to talk about temperature and efficiency, as obviously not all motors and controllers are the same, plus of course efficiency is a map rather than a fixed number. If we know the efficiency at say 25C of the individual components and calculate the battery to wheel serial efficiency by multiplying each component by the next we end up with the actual power at the back wheel. Volts x Amps at battery x serial efficiency. If I had the spare cash it would be fun to use a powertap hub to see the combined rider and assist output at the wheel and a powertap or similar at the pedal crank to measure rider input. With a few simple sums we’d be able to genuinely determine the total and rear world power split. Enjoyed your battery book. Thanks.
Good info, been messing with ebike for a while and came to these ame conclusions. However I have also read that torque numbers can be fudged and interpreted differently so also not a reliable number to focus on. Best bet is to look at all the numbers together and also look through forums etc to see what people are saying about a particular motor you are interested in. Mid drive is tempting me but for reliability I just convertedmy mountain bike with full suspension to 1kw hub drive and it's a nice powerful fast ride.
ADO are interesting on this front. The ADO Air 20 has a 250W battery and 350W on the international version. However, both are apparently marked as 250W on the motor. It lists as 9.6 amp hours (36V battery). Which means it is basically closer to 350 watts peak on the international version while artifically limited via the controller on the EU version and does not include the thumb throttle. Their Beast ebike has a 250W motor listed ONLY but is 14.5 amp hours (36V), which means it peaks at around 522 watts. Lots of shennanigans going on with many of the manufacturers especially people like Engwe ;)
Wouldn't torque increase as you increase the operating voltage though? So the torque rating would only be applicable for the listed controller / battery. If I throw a 52v battery in a 48v controller, the torque produced would increase
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It's a blessing this channel exists to give answers about these things. This guy just get straight to the point and explains everything in detail.
And i was waiting for someone to come and sit on left side of that couch lol
Lol
@G MONEY They are bots, I don't know why you are yelling at bots but ok.
Rule of thirds, baby.
@G MONEY BEEEAAAANNNNSSSS
@G MONEY BEEEAAANNNNNSSSSSS
Excellent tutorial. I had to read and study lots of detailed books about this subject to understand the differences and how they related to each other.
In less than 11 minutes, you've perfectly, clearly and concisely described and explained what I had to learn the long and hard way.
I wish this video had been around when I was learning this stuff.... well done!
I have waded through all of the amateur videos, the informed videos and the well informed videos and I have gleaned a little knowledge from them all. Some, more than others ( like testing + and - wires at both ends before frying a new £200 battery) . But now I feel I have arrived at Ebike University. Greatest Ebike channel of them all IMO. Thank you from Ireland and keep up educating the masses.
Thank you for your clear explanation of the power levels that’s really been a great help. Thank you so much
🌝🌚
Well, for those like me, haha, I was unable after welding batteries purchasing BMS's to be able to understand exactly how that final S series was counted. It finally hit me after going back to basics, watching these very easy to follow builds. That, the final S count that I was always missing was: the very first battery that has both the positive and negative going to it, even though it wasn't exactly making an S series connection, was the very last counted Series battery. Maybe very easy for everyone else, but had been banging my head around that for months. So, Thank you so very much for helping me stop feeling so stupid and knowing for sure I knew how to correctly look for and buy the correct BMS for the battery builds I was doing.
That's not correct. In a series connected set, positive is on one end, negative is on the other. the path of electricity has to travel through each battery one after another.
Can a maximum current ina. Battery be 32a&72v? Is that correct???
Great video... Yes, torque ratio to watts is the most important measure. It's how the bike will perform off the line and up hills. Basically how the bike will 'feel' to the rider. - Sluggish vs muscle.
last but not least wheel diameter (in case of hub motors which put less strain/wear on the mechanical drive train) plays into how efficiently those Newton meters actually propell the vehicle forward. The smaller the wheel the sooner rotation and efficient rpm can be achieved.
I have a rickshaw which often amounts to a total system weight of 600+kg, but with a geared hub motor in my 16 inch front wheel I'm getting the most when starting the race at the green light at Octoberfest outrunning my colleagues with 200kg less who are running the same 250W nominal system on slimmer tires but with 26 inch diameter.
(it might also have to do with me being the GOAT in rickshaw racing but don't tell them that ; )
The Ebike community seems to love the “I could climb a hill” selling point, but I’m over here in Florida getting reminded every couple videos that hills exist. Cheers.
The first time I watched it I didn't understand, I had many doubts about... . now it became clear as water. thanks a million
WOW, Thanks a lot! As a retired electrician, Your explanation clicked 100%. Something else I see is batteries being rated in watts with no reference to amp hours. Often digging for other sources, I find the '360 watt' battery is 48V and doing the math get 7.5AH which is kinda small... Just liked/subscribed and bookmarking this video!
im unsure tbh
360 watt would refer to the motor power the battery should be rated in AH
however what I think might be going on here is for reasons I don't know they could be rating the battery in watts referring to the motor its suitable for for example calling a 32 volt battery a 250-320w battery because that's what you mostly use for those and calling a 42v battery a 500-700 watt battery with a 72v battery being a 1000+ watt battery
for reference my bike is specced as follows
350w motor
32v battery
11.5ah battery
if we wanna rate my battery in W/h as opposed to A/h my battery is 368W/h in capacity
but generally when it comes to ebikes if its talking amps there referring to the AH of the battery
if there talking watts its almost always the rating for the motor
and volts being what the battery is delivering
there's a whole thing for over voting the motors to get a lil extra performance as well as going for higher voltage batterys to reduce charge times as all chargers are limited by there amp ratings so upping the voltage is a easy way to get more watt hours into the battery faster without pushing more amps I've even seen some ellect to install 72v batteries and regulate them down to 32 to benefit from having a smaller battery and faster charge times but still having the range a larger lower volt battery gives them
@@Sarge92 That's a lot to wrap one's head around... I note that 'A' also refers to controller ratings. We could really confuse things saying my T42 is only 1.1 KVA peak... If a controller is rated up to 72V and being used on a 48V hub, what's the risk of going in series with a 12V agm with the 48V li-ion to get 60V operating voltage?
The battery rating in Wh is more honest than giving A*h, as the Wh charge actually defines the amount of energy stored in the battery. A good comparison factor is the battery consumption in Wh/km or Wh/mi. Giving only Ah rating (without the voltage) is deceitful. Giving Wh is honest. Big brands always give the battery rating in Wh as not to deceive the customer.
@@StefanMikulski You say "Giving only Ah rating (without the voltage) is deceitful".... I submit, So is Wh - (without the voltage). 360WH could be 36V 10AH or 48V 7.5AH... Speed comes from voltage. VA's or Watts is actually 'power' giving an idea of how long a load will run. Or, in the case of a motor, it's hp rating since 742W=1hp.
@@johnw65 speed comes from voltage? How comes my 36V Specialized Turbo Vado 6.0 can get at 45 km/h (28 mph) while a derestricted 48 V Specialized Turbo Vado SL can only get at 34 km/h (21 mph)? No, the voltage is irrelevant here. Speed comes from the motor power, which is mechanical 520 W peak in the former and mechanical 240 W in the latter. The speed also affects the battery energy draw. That's why the former battery is 604 Wh (36 V 16.7 Ah) and the latter is 320 Wh (48V 6.6 Ah).
This would be a great tutorial lesson put into a full series. Explains things in an everyday way of understanding.
Finally a honest and clear picture for a newbie!
I know most are watching this for the knowledge of the ratings, but this has actually taught me a lot about battery building. A concept I never understood was the max wattage rating, and now I understand, its just the max current the battery will put out multiplied by voltage.
your channel has been immeasurably useful in getting into ebikes!
Looking forward to your DIY motorcycle conversion book and video series!
Wish this video was there 3 months ago when I was struggling to understand these things, thank you! :)
Thanks, here in the UK, as you say we have 250w continuous, I am very happy for the manufacturers to allow us to overamp their motors for more power, they know we will not burn them out at say 750 watts for a reasonable time.
I may be wrong, but I think the Bafang 250, and 350 are the same motor but different controllers to allow more power.
It is a way of giving us a good product and stay within regs, a point you made well.
only danger with overamping would be being involved in an accident having your bike looked at by a sworn expert making you liable for operating an illegal motor vehicle.
The bike squads in Germany are no fools and are regularly making examples of obviously overpowered "250W"ebikes (which could be legal if they had a moped plate and all the other items required for fast ebikes)
@@velotillthis is why the laws are a bit dumb. What should really happen is there should be a law on use of peak power to allow fast starts and uphill runs tied to the amount of torque provided by the rider. Fast starts for 10 seconds up to 10 kmph on flats (until you pedal past it) and during cornering to get you out of trouble and when hitting an incline allowing the peak power to stay on for as long as you provide enough torque to keep up to the maximum speed llmit of 25 kmph.
Micah-this was helpful regarding power, with good examples. I would be interested in hearing a similar approach to torque ratings. Thanks!
Very enjoyable and clear explanations of a topic that is usually portrayed as confusing and impenetrable.
1:27 Yep, a big 10 ton trolleybus has an electric motor rated at 100kW. That low! But that is the continuous power. And trust me, during acceleration from standstill, the motor drives much more current than 175A (runs at 600V). That is the reason why there are components limiting maximum current, as the motor would happily take all it can get. And yet, differentials and axle reductions wear out sooner on trolleybuses than on buses. And if the regulator malfunctions, a trolleybus can easily do a burn-out on a dry paved street. Of course, do it three dimes and you can replace the whole axle, if the CV joints on the shaft between the motor and differential do not break sooner. Or you blow the circuit breaker in the trolleybus (should break around 380A, but that is only theoretical) or you trip the breaker in the electrical substation feeding the section where you draw your power from. If you had no protection circuits and a very powerful source, applying 600V directly into the motor would most likely result in lightnings flying out of it and ripping it from the frame of the trolleybus, destroying everything between it and the wheels of the driven axle(s).
My head hurts
The ultimate ebike guide please,if I do not win a book this time I will buy it. Great video
Customer:How many watts?
Manufacturers: it's complicated...
I mean i would make the motor faster than needed too and then use that for acceleration with speed limiter 😂 it just makes sense🤷
This is my first time to one of your videos. I’m subscribed!! I understood everything while you talked, but need to listen a couple more times to really understand.
I’m shopping for my first ebike. It isn’t easy. But, you have helped a lot!! Thank you! I’m going back to listen to your other videos! I needed a white board with your numbers on it. Visual learner, here. Good job!
Thank you! I'm getting a DUAL motor, DUAL battery E-Cell Monarch 1500 and now I know how to find the real power of each motor.
Thanks for explaining some of these terms as they apply to the ebike market place. I just recieved my T-1 replacement and didn't understand why the new motor was labeled 250w. Now I do.
You forgot to mention that a particular motor designed to go with a specific voltage will not put out more power just by changing the controller, the voltage will have to go up, which means changing the battery as well as the controller. Ohm's law hasn't changed!
That’s totally wrong. Not only have I swapped out batteries from 48V to 52V, I’ve swapped controllers after switching to 52 and my CLyte 3540 (rated at 1000W) and upping my controller from 26A continuous to 35 continuous definitely puts out more power. There are literally thousands of examples of this to choose from, not just my experience of riding my DIY ebike 30,000 miles. Yes, it is more susceptible to heat (loss), but it’s certainly not all lost to heat. I assume you don’t have an ebike. Ebikes.ca has a simple motor calculator and you can input values for many types of motor and controller combinations and see the data yourself.
I will increase the current from 48v×10a eg..to 48v×25a
What you call power is the torque which is a function of electric current not voltage. Varying the voltage would vary the speed. Amps = Torque (more powerful), volts = speed (faster)
In UK (and EU) the max continuous power output is 250W for an electrically assisted bicycle but if you want a higher output bike then that is classed as an electrical moped i.e. a motorbike driven by a motor and pedals. The issue with this comes from the requirement that to be an electrical moped it needs to be type approved or to have an 'Individual Vehicle Approval' to show that it complies with UK/EU vehicle build laws and that it will also need to be licenced, taxed and insured for a minimum third party cover. The rider must also wear an approved i.e. motorcycle crash helmet and preferably protective clothing and although not mandatory, the police might pull you over for inappropriate wear if you had classic Lycra shorts and top on.
Thank you this clear explanation! Usually, when people ask for the power of a bike (or car), they want the max (peak) power, like with petrol engines.
With motors I just look at the newton meters of torque and the Rpm’s after checking the volts and amps. Thanks for the video
Thanks for your clear explanation of ebike power. I’ve been researching the subject for a couple of weeks, and yours is the best, most straight forward explanation yet. Again, thanks. Please keep up the good work.
A really useful tutorial/vlog. I had wondered why there is so many different claimed power outputs
Very good explanation of "power". Keeping it simple using VA can help those not familiar with end to end input to output and the various losses along the way. Something to consider is the fully charged battery versus the nearly discharged battery. Power is greatest when the battery is fully charged and is minimal with a mostly discharged battery.
I love you dude you've taught me so much and getting all this info makes me knowledgeable enough to build an ebike
First class and full marks - easily one of the best explanatories I've ever seen. Thank you very much and happy travels (remember: "No helmet? NO WAY!").
Excellent information, I’ve been using the torque number and 750 W as my comparison point since my neighborhood is hilly. My driveway has 7+ feet rise of elevation 😂
This is my random comment, The Ultimate Do It Yourself Ebike Guide.
Thank you for this video, it explained a few things I was trying to figure out. 500W 32kmh/20mph limit where I live.
Sooo.. My Super73 SG1 (EU version of the S1), has a nominal rating of 250W, which is the maximum allowed wattage in Europe. The motor also says 250W etc. However, having a 48V battery, and the controller's current is rated at 10A with a maximum current of 20A, it's very obvious that this is a 500W motor with a peak at almost 1000W, which is the same as the original American S1. The European version is electronically limited though, but I've unlocked it by plugging the US throttle in, and I'll just say that if this is "250W", then it's the most powerful 250W motor in existence 🤣 Ain't complaining though!
Thanks Peter for clarifying electrical power ratings and some extra tips (torque).
One of your best videos! Very well explained, I wish I knew this before I bought my first ebike a few years ago.
You talked about this several years ago (I think too, it’s also in your book) good to hear again. I think you put it better here. It’s not as text book more layman’s terms I guess. Same but more relaxed and I think easier to understand. Good to hear again very important. And yes we do benefit if we know how to take advantage. That we can (w/aftermarket controllers) put together a bike that we love to take for a ride!
Thanks
Reminds me of some lakes will have a limit of 10horse motors. But some people will put a 10h cover on a 15h motor.
Thank you so very much I have known watch amps and volts since high school but the Newton meters now I have something I can really use thank you so much.
I love how continuous and peak power has an excellent explanation to them, telling you exactly what they're about, then you get to nominal power and it's basically 'this means nothing. it could be true, it could be false, and even if it is true you won't know "how true" the rating is unless you test it.' It is pretty hilarious and i can see where the frustration can stem from that.
nominal is just a label to please lawmakers
Vary informative video I am an ebike and battery geek and I love learning new things about anything to with eather of them. Thank you
You are best profesor i ever had.
It is easy to explain something when you know it.
I enjoy just to listen you.
Thank you very much and keep going
this channel is quickly becoming one of my favorite youtube channels, this video is extremely informative, i dont yet have an ebike but my father and i are both interested in getting an ebike so we have been trying to soak up as much info as we can before purchasing our first ebikes, thanks for the all the informative videos you put out there :)
Build one. It's cheaper and you get to know how they work
@@marcus.H that would be nice, however that's not currently financially viable for us
@@acehighdan sorry to hear that.
Hopefully parts will become cheaper in coming months.
One price of advice I would give for those just starting out is that if you pick up a Liitokala hoverboard battery from AliExpress for $25 you have got a sufficient battery to get you started with a 36v kit.
If you could do a shift extra each week at work, you may be able to save up the $150 needed for the motor and controller in a short time
Or wash cars or Windows for money. Or now lawns
Finally, someone explained those rating, thanks
Thanks so much for the information. This has been extremely helpful in purchasing 3 e-bikes for my family and I.
I have been watching your videos for a long time and thanks for your information I learned a lot throughout time!!! I became scooter technician and a lot of information came of watching your videos!!! Thank you my brother as always! Great content!!!
Just great! Very informative. You really have a great talent and know haw to share knowledge in a clear, understoodable manner! Greets form Poland!
Clear and concise explanation. I have learned a lot about ebikes from your videos.
Thank You!☮
Just got my first spot welder from banggood. Tried it out and love it already. Cant wait to make my first pack thanks to your books!
Which one did you get?
That is going to be my winter project, I have been ordering LiFePo4 32700 batteries, to make a 16s 3p battery pack. Probably will go with a Daly BMS. I'm also curious what welder you got, and what thickness of nickel you plan on using
Here are results of that tab welder. Now im not an expert on welding but maybe someone can answer my question on it. Again this is a first time thing for me and maybe I bought a bad welder but if anyone know's more about how good or bad I did id love to know. Thanks again!
ruclips.net/video/LERZ14QSksE/видео.html
During my studies for electrical engineering the lecturers told me that the advertised motor power is usually mechanical. the mechanical power is calculated by multiplying angular velocity and torque. Mechanical power is the power you get from motor. The power you were talking about was electrical or the input power.
Great explanation of ratings on the electric motors. Easy and clear.
Thanks to all the information you bring to use, I'm building my first ebike
Great explanation of what can be a tricky subject.
The power rating system reminds me of the Japanese gentleman agreement between the Toyota supra and Nissan GTR when it comes to horsepower making in the same
Great explanation of E Bike power. I made some useful notes esp power calc. Thanks
I want one! Thank you for clearing that up.
3 people bought an underpowered bike.
lol!
Definitely would love a chance to get one of your books.
Yes & Motors have torque & power curve. A hub motor may find life hard turning slowly on a steep hill & heat up fast, but a mid drive is geared crank speed, so should be in the middle of its design range hill or flat. & its also important to remember the gearing factor difference between Torque for a hub motor & a geared mid drive.
Very interesting information as always. I’m so glad you mentioned Newton meters as that’s how I judge the power of a motor. Seems like your bicycle clock like mine needs new batteries.
The basic direct drive hub motors like violamart have the same direct drive hub motor but the controller varies, it could be sold as 500W, 750W, 1000W, 1500W or 2000W with only the controller varying and the hub motor remaining the same. How is that motor rated. Also if you buy lets say a 1000W version and use it with the minimum size battery it will accept about 48V at 12Ah in the road legal mode it is 250W approx (more like 300W) but if you disconnect the wire you get a 50% boost to 450W approx but the battery can peak at about 960W (20A) output for about 60-90 seconds or about 700W in road legal mode. It's confusing as clearly the battery BMS and controller and motor are not at the same level. I guess the BMS dictates the actual power the motor can receive, the controller could handle more and the motor itself could handle much more. I'm not sure what the nominal or continous rating of such a hub motor is but I guess at least 1000W. I've heard of Bosch motors easily peaking over 700W despite being road legal but many would view the Bosch as road legal and the home kits as not and its one factor why people pay more for a Bosch bike as they worry about the legal implications of a crash with a kit motor hub. The law seems a mess. However here in the UK I don't think anyone has been prosecuted with a home kit and you wonder if the police just check that it doesn't assist beyond 15.5mph because its the only simple test they can do.
I have the 1000 watt voilamart hub motor, and it peaks around 1200 watts according to the screen. I bought the voilamart 1500 watt controller instead of trying to play with the internal shunts on the stock controller. It has been sitting on my work bench for over a month now, cause I wasn't sure if the hub motor would take it or not (wire size)... I wish Micah would respond to comments... I think I should be ok as long as I don't full throttle it, I just want some extra torque on take off
@@chrisnmichelle0218 Can I ask what battery you are using both volts and amp hours plus if you know what peak current it can deliver for how long? Which cells are you using if you configured the battery yourself? I have the yosepower 48V 12.5Ah hailong case battery pack which uses Samsung 2500mAh cells which allows a peak current of 20A for 60-90 seconds. As stated above pretty much the minimum the 48V 1000W motor will accept which I think is stated as 48V 11.5Ah minimum battery. I use it in the restricted street legal mode partly due to legality but also because the battery is such a low capacity for this motor.
@@bonzobanana1 16s 1p 48v 20ah lifepo4 BTR power battery (www.ebay.com/itm/282691708617) it is made with lifepo4 pouches, not cells. 50A continuous discharge, 100A max discharge. The battery is great, but it weighs almost 20 lbs and I have to mount it on a rack behind the seat which throws the weight balance off. I have been buying 32700 liitokala lifepo4 (m.aliexpress.com/item/4000073953939.html?pid=808_0000_0109&spm=a2g0n.search-amp.list.4000073953939&aff_trace_key=0f27108c4dae4f51866478090c8a265e-1598364242794-04812-UneMJZVf&aff_platform=msite&m_page_id=6236amp-8afh0fKpUqPr1GppmYPgnw1598364304447&browser_id=3d094fe9d33b4a2fba89779d51150c11&is_c=N) 3.2v 7ah batteries, with continuous discharge rating of 35A per cell. I plan on building a 16s 3p battery with the 32700 batteries, and a 50 amp bms for it. That would get me 51.2v 21ah battery with a continuous output of 50 amps limited by the bms, I plan on using a bms made by Daly, as they have great ratings. I'm kinda sold on lifepo4 batteries because they have a much longer lifespan of 3000 charges (I don't ever drain my batteries dry) and just being a safer and more stable composition where I don't have to worry about thermal runaway if I push the batteries really hard.
Really outstanding and thorough review of motors. Thanks Micah!
thanks, awesome video, very thoughtful and very nice of you how you explained how companies don’t actually lie but in fact what they do is to comply to the estates regulations and just create misconceptions of legit information of the tag/specs readings. Just can’t appreciate enough bro. have an awesome life. 👌👍👍
Also, a couple other things:
European "continuous rated power" isn't continuous power! It is, to quote Regulation EU No 168/2013 Article 3(35): "‘maximum continuous rated power’ means the maximum thirty minutes power at the output shaft of an electric engine as set out in UNECE regulation No 85"
And "maximum thirty minutes power" from that UNECE regulation: ""Maximum 30 minutes power" means the maximum net power of an
electric drive train at DC voltage as defined in paragraph 5.3.1. of this Regulation, which a drive train can deliver over a period of 30 minutes as an average"
Additionally, there's test procedures in that regulation that define it better, and where the loophole comes in - the power level must be the manufacturer's best estimate of maximum 30 minutes power, and the RPM must be in a speed range that allows greater than 90% of maximum peak power (which is determined in a separate test). If the manufacturer estimates too high, of course, it'll fail the test and they'll have to re-run it, but if they estimate too low, it'll pass.
The US regulations not actually saying what power rating standard is in use make me think the safest bet is to assume the more (but not the most) restrictive interpretation - 750 W peak output power. I don't think any of the vehicle regulations in the US are actually using continuous power (whether over a specific time or indefinitely), but then the US doesn't usually restrict power output, either, outside of e-bikes and state laws restricting what can be used as a moped/motorized bicycle/scooter without a motorcycle license.
Then, there's one problem with your methodology of determining peak power: efficiency. So, just because you've got 36 V, 15 A coming from your battery doesn't mean you have 540 W coming out of your motor. If your motor/inverter system is 85% efficient at peak power, you've got 459 W coming out of the motor (and 81 watts of heat that your controller and your motor need to dissipate), and that's your real peak power. (There's additional drivetrain efficiency considerations downstream if you have a mid-drive, but my understanding is that power regulations care about motor output, not wheel output.)
US goes for Continuous power. Rating the motor by peak, is incorrect for it's performance. Peak is the RPM and torque a motor goes through before it reaches it's end power point, then tapers down in power. So once it's up to speed, it's not at it's peak power anymore. Same as Gas cars,etc. If they ruled for Peak, Electric/Gas devices would suck.
It's like saying, This car can only have 500rpm and such % of torque. You realize how SLOW that car would be to get up to speed? It'd be like a snail trying to get up to 40mph, in 20mins.
So if a state has a rule of power of a 750watt motor as limited. That is continuous power rule. Not Peak. The motor can have 2x more Peak, because that start power the motor goes through. Again like a gas car,etc. It's the start of the motors run to get whatever it's pulling/pushing up. Then it lowers down to it's continuous power performance which runs at a stable set.
Nobody cares and no one reads your comment, stop looking for validation of your knowledge level in RUclips comments, it's very sad and childish.
@@TheAvkdutch You're a great example of how dumb the world is. "Will listen to this stupid twit on this epic website that doesn't know crap, But not to someone who knows the truth on a comment."
You should've just never commented, Cause you just made yourself look like a fool and just showed everyone else like you how dumb they now can see themselves.
This is the best described video of ebike motors anywhere. Thank you.
from many months i wanted some one to explain about this topic thank you for the content.
Hi I have just placed an order with amazon for your book on lithium battery building , I have had really good / the best information on e bikes from your RUclips post thank once again
Awesome basic information that will go along way for the Ebike noobies like myself. Thanks
Very nice video and didn't know, how much i wished for this video until i saw it!
Thank you for this valuable information. You explain the technical aspects in great laymen's terms.
THIS WAS ALL THE INFO I WAS LOOKING FOR! thank you so much for this video!! you are amazing
hey Micah, Great videos, i used your lesson to make my first and 2nd ebike. thankyou and keep up the good work
Hey, just a heads up. Several of your links to Aliexpress are dead. The 18650 cells link goes to a charger. The 1000 watt complete kit is dead. There are others that are dead, just some housecleaning to do with your links. Thanks for the videos! I'm a fan.
Micah, I've been looking for an explanation of what "nominal" really means, thanks!
I still did not get it🥲
You should run a non profit association that lays out a spread sheet of the bikes and all their true non biased ratings. …you know the truth about these bikes. Well done video!
Great video. Love to see you do a how-to upgrade your e-scooter video. Thanks
Awesome! I've been so confused on those ratings, thanks for the help!
Jose Munoz I’m still confused. Maybe if he got off that couch.
More great info in my quest to understand & build batteries. Thanks
This is the most in-depth explanation on this topic to date.
Auto manufacturers underrate their motors too. The 06 Chevy cobalt SS LJS supercharged 2.0l motor is advertised as producing 215 crank hp. I assume this if to keep insurance rates low, because they routinely dyno at 235hp at the wheels before any mods. I'm happy to get an underrated motor in my e-bike because excellent reviewers, such as yourself, make head to head comparisons revealing the "truth in advertising" very quickly.
Hey nice job that clears up my confusion. Appreciate it.
Pretty good. I find it helpful though to go to the next stage as what we are trying to do is compare the human power at the back wheel compared to the assistance power at the back wheel. And for that we need to talk about temperature and efficiency, as obviously not all motors and controllers are the same, plus of course efficiency is a map rather than a fixed number. If we know the efficiency at say 25C of the individual components and calculate the battery to wheel serial efficiency by multiplying each component by the next we end up with the actual power at the back wheel. Volts x Amps at battery x serial efficiency.
If I had the spare cash it would be fun to use a powertap hub to see the combined rider and assist output at the wheel and a powertap or similar at the pedal crank to measure rider input. With a few simple sums we’d be able to genuinely determine the total and rear world power split.
Enjoyed your battery book. Thanks.
Nice video! This helps me to understand the about the watts and controllers. Thanks
I like to learn stuff and learning from you is easy cuz you just go step by step I like that thank you
Good info, been messing with ebike for a while and came to these ame conclusions.
However I have also read that torque numbers can be fudged and interpreted differently so also not a reliable number to focus on.
Best bet is to look at all the numbers together and also look through forums etc to see what people are saying about a particular motor you are interested in.
Mid drive is tempting me but for reliability I just convertedmy mountain bike with full suspension to 1kw hub drive and it's a nice powerful fast ride.
I always wondered how much power I was putting out to my motor ,now I know multiplying the voltage by the controller amp / thanks
THANKS FOR CLEARING THAT UP. SMARTLY DONE AS WELL..
Pleasant surprise, companies delivering more power than they are promising on paper. :)
ADO are interesting on this front. The ADO Air 20 has a 250W battery and 350W on the international version. However, both are apparently marked as 250W on the motor. It lists as 9.6 amp hours (36V battery). Which means it is basically closer to 350 watts peak on the international version while artifically limited via the controller on the EU version and does not include the thumb throttle. Their Beast ebike has a 250W motor listed ONLY but is 14.5 amp hours (36V), which means it peaks at around 522 watts. Lots of shennanigans going on with many of the manufacturers especially people like Engwe ;)
Another good explanation, thanks.
Love the explanation!!! Keep it up !!! Ebike 4 Life!!!
Brilliant video so enlightening,keep your excellent videos coming thanks.
Excellent tutorial. Thank you I have learned alot from it.
Wouldn't torque increase as you increase the operating voltage though? So the torque rating would only be applicable for the listed controller / battery. If I throw a 52v battery in a 48v controller, the torque produced would increase
Just bought my first ebike. Waiting to get it. Looking to buy solar next to go totally green.
Thank you - very helpful. I look forward to continue to learn from your your youtube posts.
This video did clear a lot of questions that I had, Thank you.