1982 MB-5 30kW peak 230 lbs Complete new VIDEO! 82mph

Thanks for the info. I'm going to pass on looking to buy this one. The main reason was I thought it was significantly lighter. I got my Kawasaki KE100 down to 95lbs for a rolling chassis, and I'm probably not going to do any better than that, short of buying a Zero XU or X frame.

I think yours came out really well, looks like a lot of fun.
 
I have a Perm132 with a Kelly 72v 600amp controller (will not run that many amps in the near future!) that I got from DocBass.
 
Drove down the highway for 7 hours today in my car... had nothing to think about.. boring ride. This image came to mind of this cosmetically wonderful enertrac rear hub with a 18" rim.. Got me thinking what performance I might get if I had them wind it for 6 phase use and I upped the voltage to 32S (105.6 nominal). I think is does 60mph on 96V with 3.5" tire. I think 10kW continuous with no ventilation. This would also make the bike look better and give me a couple miles more range.

The other thing I thought about was taking the current build out on the interstate for a second person video run from cam car chase... hmm.. had it up to 80mph now on a slight down hill..
 

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That's a pleasing looking bike by e-moto standards, but it still looks like a motorcycle humping a cat box.
 
have you been having overheating problems with your hubmonster at all? if not it might be possible to put the hubmonster in a larger rim. i donno if you saw this already, but Toby82 managed to get the hubmonster in a 16in motorcycle front rim. it would definitely be cheaper than buying a whole new motor just for a larger rim. but im sure the enertrac would also have a bit more power/less problems with overheating (especially if you bought the oil cooled one!) another thing with the enertrac is that you would probably need a new custom swingarm.

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Enertrac would swap right in.. The normal one is 190mm. My swingarm can accommodate 23" of tires. Idk about flat width however

Current motor needs more cooling for it to be dependable. I'd like to open up the vents 500% and make a shroud with a 700cfm blower in it.. Especially if I go to larger 21-22" tire. It will inevitably happen, though I dot have much use for 86mph

I'd like to machine my own hub motor some day.. With water cooling.
 
My temperature threshold was set wrong. it was basically putting the motor in inefficient regions (30-50mph) for too long under load. With 200/230A setting on each kelly and the temperature handicap removed, this thing speaks! Unreal. It's time for real video. I'm about to hit 1000 miles.
 
MOtor temperature spike a lot when under extreme load. every motor does this.. obviously spikes higher when motor is in critical state. I'm monitoring the windings directly, the primary heating source and hottest element. I had CA set to roll back throttle output from CA at 115C, and cut off at 145C. What you find with temperature dynamics in motors is that the stator temp never a direct linear reflection of magnet rotor temp... magnet ring is heated primarily by convection of stator... so what happens is the magnet rotor is usually fairly steady and balanced in temperature compared to stator (when motor is always spinning). if you are trying to keep magnets below 70C (with a vented motor), you don't need to cut off throttle so early. I was getting full performance for about 5 miles and then when temperature stabilized I wasn't getting full performance (magnets 50C). Make sense?

The issue I think may have been compounded because the stator was spiking at 50% rpm band, forcing me to go full throttle where the motor produces the most heat. I haven't analyzed this.. just a theory that it's contributing to waste heat.
 
Nice acceleration at speed. 30 / .746 = 40hp, not 20!

If you stretch your position out / lower your seat, you would certainly get better range.

Dropping my seat on my ebike 8" and moving it back cut about 20% off my wattage at 30mph.
 
hillzofvalp said:
Working on it.

And no it's 20Hp to the wheel. 40Hp at the battery. Bldc make peak power at 50% efficiency.
Click to expand...

Actually that's at maximum power, which occurs at full saturation. Efficiency at peak power increases pretty quickly the as current limits are set lower than saturation. We don't know what saturation is, but I'm confident that I'm running safely below saturation at 245A from the battery. To give you an idea of how high efficiency can be at peak power, the factory uses a 80-100A limit with it's different scooters, and with their tuning the motor is 89-90% efficient at peak power. No doubt we're running below that, but I'm sure we're getting at least 75% efficiency at peak power, maybe even in the 80's. Otherwise we'd have tremendous heat problems.

Speaking of which, have you tried blades on the exhaust side yet? I haven't tried any optimization of mine, but I'm able to run much harder with a cooler motor than without blades. It's definitely worth the little bit of effort, since you did all the hard part when you did slots.
 
cool vid even though it is a bit shaky. and i was surprised when you said 50% eff too. i know motors like 9c and crystalyte have 50% at peak power but john's probably right about it being 75-80%. theres just no way that youre putting 15kw of heat into the motor lol. im sure the fact that the motor is wider and has more copper/better construction than the 9c/crystalyte helps in efficiency. also being a 6 phase motor, im sure this also helps.
 
Any motor will be 50% at the maximum power it can create at that voltage, but it's foolish to run current that high because heat problems are inevitable and it wastes battery capacity. Also, any motor starts at 0% efficiency on launch, so they all cross through the 50% efficiency threshold during acceleration regardless of controller settings. That's why lots of repetitive hard launches are hard on any system, and getting stuck in bumper to bumper traffic can create a lot of motor heat even going easy on the throttle.

How you ride can make a big difference with any system, and that doesn't necessarily mean riding at lower performance. When you get into high load situations like on hills, keeping speed up and a more steady throttle can make a tremendous difference. Controllers don't like the slow partial throttle stuff on hills either.

I live in a mountainous area and when I'm climbing grades I pass traffic whenever possible, because not only is it more fun to be faster on the climbs, but it's easier on the system too. Behind traffic there's always the more frequent accelerating and slowing, which makes phase currents spike around and efficiency drops. Passing traffic only to ride so hard on the climb that you're braking for the curves and accelerating out of them, can obviously be hard on the system too, but I like choosing my own speed to ride and I like open space in front and behind. I've got good ventilation, so I've yet to need to worry about heat and I'm riding much harder than ever.
 
Interesting! Well, I have an analogger I will be using tomorrow alongside a dynojet :). I will post results later this week if all goes to plan.

Shaky video.. yes. That was not planned at all. .but I was so excited to be able to pretend I could race a tesla! haha. He followed me for a while, actually, but had his wife in the car sadly... :(

May not be 15kW of heat but if it were, it's only instantaneous so really isn't that much energy. Like John says, it's the duration/frequency of the heavy loading events that kill motors. I'm always monitoring temperature. If I come back after a very aggressive run and the stator is at like 125C I'll give it a nice mist until down to safer temperatures. Fortunately for me, most of my commutes are less than 10 miles, so I can run fully aggressive and arrive at location with a safe temperature to leave it without protecting magnets so obsessively

I cruise without issues up over 60mph.. It's mostly when I do 0-50 pulls that things get warm. And no, I'm not running blades. I'm going to be doing a massive motor revamp when I have time.. involving forced air and gigantic inlets like on Zero's racing bike.
 
If your stator is getting to 125C, then I would consider that too hot. Since you put the sensor at the windings I'd call stator temp your reported temp after a minute or two of shutting down, so the copper would quickly become the stator temp and then cool down is slow after that.

Your thread title says 30kw peak. Is that reported AMAX of the CA times VMIN early in a fresh charge? Any idea of peak phase current. I'm running roughly the same total load with 245A peak battery current, phase current limit programmed to 370A, and voltage typically sagging to 103V. The highest temp I've seen is 105°C on the stator, and my gauge registers between 5° and 10° higher than ambient when the motor is cold. I hit that temp twice, once on a ride climbing some hills at over 80mph, and the other was climbing an average 20% grade. That is with ambient temps below 30°C, and my only other thermal advantage is better ventilation.

You shouldn't have to worry about temps, so if you're really getting 125°C at the stator, then to me something is wrong. Maybe it's just a combination of not putting the blades on, and having your controller set too high, but I never ran that hot even when I ran with the motor sealed. If you have your controllers set higher than mine, then you should have better acceleration than I do, but I've yet to see any videos that demonstrate you're even close to the performance I enjoy, much less greater acceleration. Was the Tesla getting on the gas, because in the clip it seemed like he was just driving gently? If he was heavy on the pedal, then yeah you passing him would be quite something, and I can stop worrying that you aren't getting the performance that I think you should. I've worried that the Kelly's aren't matching up well with the motor ever since you've reported heat.

Putting your bike on the dyno will be great. If you're really pushing 30kw peak into the motor, then we better see well over 20kw peak power out.
 
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