BLDC Motor Controller wiring for custom motorcycle

[kreal]

So I've been spending the last two weeks or so reading trough all of the forum looking for information regarding a custom project I'm working on. A "Yamasaki ym50-8b" conversion to electric, no more dirty ICE

So I finally found a motor, a brushless 48VDC 1300 watt 4800r/min from a shop called "mm-konsol"
And luckily enough a shop here in Denmark called thansen had a BLDC motor controller 48VDC 35A for a giantco e-buddy scooter.

However I am now stuck at the brushless controller wiring.
The three-phase, hall sensor, throttle and battery connection wires are no problem. But it seems I need the "key lock" wire or high brake level wire to go somewhere ?

Some information hints that the thin red wire needs 5-12V to turn the controller on, other places says it is the purple wire, very confused.

 

[amberwolf]

So I finally found a motor, a brushless 48VDC 1300 watt 4800r/min from a shop called "mm-konsol"
And luckily enough a shop here in Denmark called thansen had a BLDC motor controller 48VDC 35A for a giantco e-buddy scooter.

How much does the Yamasaki weigh (including the whole motor, transmission if any, batteries, etc) (and you, too)? And are you on flat roads or are there any hills?

I'm using TWO of basically that "size" (power level) motor and controller as hubmotors in my SB Cruiser trike (linked in my signature), and it gets me decent acceleration from 0-20MPH in 5-6 seconds or less in 20" wheels, and I would guess my trike is lighter than your YM will be when the conversion is finished (cuz it will probably weigh more than it did before). I havent' weighed the trike as it is now, but the other one, my CrazyBike2, is lighter than it, and is probably around 150lbs in typical configuration, and I weigh 170-180lbs these days.

CrazyBike2 has a bit more power, but with one of the motors in 26" and the other in 20", and it gets to 20MPH in about 4 seconds or so.


If your YM is heavier than my trike, then that power is going to take a long distance to get you up to any kind of speed, so if you plan on staying out of the way of other accelerating vehicles, you may need more power than that. (and your battery will have to be capable of putting out whatever power your controller draws, too).

But it seems I need the "key lock" wire or high brake level wire to go somewhere ?

On typical ebike controllers, the "key lock" or "ignition" wire (often red, orange, etc) hooks to the battery power positive to turn on the controller.

Brake wires are usually not connected at all unless you are activating the brake.

But since all controllers are not the same, if you want to be sure before trying anything, you'd need to check with the actual manufacturer or vendor for your specific controller.

Or to be more sure than our guesses here, you'd have to open it up and trace the wiring, and then test various wiring schemes to find the right one. :/

 

[kreal]

So I finally found a motor, a brushless 48VDC 1300 watt 4800r/min from a shop called "mm-konsol"
And luckily enough a shop here in Denmark called thansen had a BLDC motor controller 48VDC 35A for a giantco e-buddy scooter.

How much does the Yamasaki weigh (including the whole motor, transmission if any, batteries, etc) (and you, too)? And are you on flat roads or are there any hills?

Hard to say, from the specs, the original weight was 110kg https://scootergrisen.dk/scooterhjemmeside/download/yamasaki_ym508b_brugermanual.pdf
So I'm guessing the final weight will be less, taking in around the batteries will be from a dolphin case carried in a backpack. http://dillengerelectricbikes.co.uk/spares/electric-bike-kit-spares/bafang-8fun-batteries/nt-style-48v-10-4ah-samsung-battery-bafang.html. Until I can find another solution. There are no hills in Denmark

I'm using TWO of basically that "size" (power level) motor and controller as hubmotors in my SB Cruiser trike (linked in my signature), and it gets me decent acceleration from 0-20MPH in 5-6 seconds or less in 20" wheels, and I would guess my trike is lighter than your YM will be when the conversion is finished (cuz it will probably weigh more than it did before). I havent' weighed the trike as it is now, but the other one, my CrazyBike2, is lighter than it, and is probably around 150lbs in typical configuration, and I weigh 170-180lbs these days.

20mph is what I am aiming for. For around 20 miles. The bike is and will be a moped classification, so this is perfect!

On typical ebike controllers, the "key lock" or "ignition" wire (often red, orange, etc) hooks to the battery power positive to turn on the controller.

So directly to the positive 48v of batteries with like a 2amp fuse ?

The best wiring diagram I can find is this. It should be similar.


Thanks in advance!

 

[kreal]

OK I made it work. I took the chance and it was the "key lock" or "ignition" wire that needed positive.

Thanks amberwolf for pointing me in the right direction!

 

[amberwolf]

Glad it worked.

Hard to say, from the specs, the original weight was 110kg https://scootergrisen.dk/scooterhjemmeside/download/yamasaki_ym508b_brugermanual.pdf
So I'm guessing the final weight will be less, taking in around the batteries will be from a dolphin case carried in a backpack.

So originally it was around 240lbs. That's way more than my trike probably weighs. Let's be really generous and say the engine and stuff was 100lbs, so that goes out. Let's say your tiny battery and backpack and wiring weighs 15lbs, and the motor and controller and hardware to hook them all into the frame weighs 30lbs. So now you're back to 185lbs, which might be similar to my trike. I don't know what you weigh, but if you're around 170-180lbs like me, then you will probably get the same acceleration I do, if your motor/controller/battery system does the same work in the same way.

That means that if you don't mind taking say, 20 seconds to get to 20MPH from a complete stop, the existing controller and motor might work, if you have a battery that can supply at least 35A for that long, repeatedly, for however many stops and starts you have on your rides.

(note that I have no data on your specific motor, and you havent' said anything about the gearing ratio either, which along with your wheelsize will make a lot of difference to how well your motor works for your max speeds and your max acceleration / torque. mine is "geared" by wheelsize, motor winding, and battery voltage for >30MPH top speed, AFAICR, so I still have good acceleration right up to the 20MPH, but I don't have as good a startup-from-stop torque as I could if I geared it lower).

http://dillengerelectricbikes.co.uk/spares/electric-bike-kit-spares/bafang-8fun-batteries/nt-style-48v-10-4ah-samsung-battery-bafang.html. Until I can find another solution.

I don't have enough specifics on your system and setup's usage to know for sure, but that battery probably isn't going to do what you want, by itself. You may need at least two of them in parallel.

Using some guesstimate numbers of my own for my vehicles, based on memory rather than looking up the data:

It's only 10.4Ah, so if you ended up using power like I do on SB Cruiser, you'll get only about 10-ish miles out of it at best. If you use less, like CrazyBike2 does, you might get 15-16-ish.

It depends on how much power you use per mile, how many Wh (watt-hour). You can also use Ah (amp-hour) per mile, but most of the time people list their "efficiency" as Wh/mile (or Wh/km; sorry we're still yardstick barbarians here in the USA ). If you know anyone with a vehicle the same as your but electric, you could directly compare with them to find out a range guesstimate of your own, assuming their system is similar enough, and their riding style and terrain and weather/wind/etc are also the same.


If you have zero stops and starts and no wind (or a wind at your back all the time), you *might* make your 20 miles, when the pack is brand new, but I doubt it would do it even then (and it will lose range as it ages). If you air up your tires nice and hard, it may help, too, but the squishier they are the worse it will be.

If you were on a bicycle, or a more aerodynamic vehicle, it might not take as much power, but based on my own experiences here in flat Phoenix with my heavy bike and trike, I'd venture it'll take you closer to 1Ah/mile than the 1/2Ah/mile a lot of bicyclists might get (without pedalling).


Also, it doesn't say what it's C-rate is (meaning for this instance, how many amps you can continuously pull from it without stressing it). Usually this is stated as a number times the capacity, so if the pack as a whole were 2C capable it'd be 2x 10.4Ah, so 20.8A max. Some also have a burst rating of a few seconds, so it might be able to do say 3C burst, for up to 31.2A max.

Assuming it's made of Samsung 18650 type cells, there are some that are high capacity but low C-rate, and some that are lower capacity but higher C-rate. Look around the forum for Samsung 18650 and there are a number of threads about different versions with various data, if you're curious.

But we cant' know which ones it's made of unless some other website tells you, as that particular one doesn't.

Either way, it also depends on the BMS in the pack, if it is rated at least 35A output capability, because if it isn't, it will cut out as you try to acclerate from a stop as the controller tries to draw it's max of 35A, and you won't be going anywhere.

If it *is* capable of the 35A, then you still ahve the likely problem of not nearly enough range. :/

There are no hills in Denmark

That's good; it helps a lot. It's flat here, too, with a few exceptions I generally am not anywhere near--but there are some slight grades and I can see the power usage go up and down when I am on them. :/

20mph is what I am aiming for. For around 20 miles. The bike is and will be a moped classification, so this is perfect!

Keep in mind that I choose to ride (cuz of the law) at max of <20MPH, but mine are capable of more than that (>30MPH, don't know what the max actually is). So depending on your motor and gearing and wheelsize and stuff, you may not be limited to 20MPH physically (you can always limit yourself electronically, such as with the Cycle Analyst from Grin Technologies http://ebikes.ca/cycleanalyst , or other methods, if it's a requirement in your local laws--thankfully it is not here)

To get a full 20miles out of my trike, I have to carry both my 20Ah batteries (40Ah), cuz on the safe side I can only get about 17-18 miles out of a single 20AH pack, under good conditions, less with more stops and starts, higher weight cuz of cargo or hauling the dogs, etc.

I can get more than 20miles out of my bike with the same single 20Ah pack, perhaps up to 30+ miles if I'm not really hard on it and not carrying a lot of cargo or hauling the dogs.

Both of those assume that I accelerate as hard as I can from every stop until I reach 20MPH, and that I cruise at that speed as much as possible.

If I go slower, it can increase my range a bit for the first few MPH less, could significantly increase it if I go below 12-15MPH (neither vehicle is very aerodynamic).