Greyborg Cromotor Hubzilla motors, Sold Out

[zombiess]

Outstanding service from Zombiess! Really above and beyond.

More on Power Levels

I did some analysis of power in the ebikes.ca simulator. Justin has hubmotor dissipation set up for 500 watts. Let's assume for a moment that is correct. If you put in 4,500 watts and the motor can only dissipate 500 watts the efficiency must be at least 89%. The values I see are more like 87% max on the simulator, which corresponds very nearly to 4,000 watts input and 500 watts dissipated. So if these numbers are accurate, putting 4,000 watts into the motor puts it right near maximum dissipation. So I would interpret when they say 4,000 watts maximum, that it is under ideal conditions. It is not safe unless those conditions are met. Anytime you exceed that it better be for a very short time, and really you should be monitoring winding temperatures.

Efficiency drops with RPM as we know. From the simulator, 87% was at 500 rpm with 150kg mountain bike on 24" tires. I got 73% at 100 rpm with the same setup. These correspond to about 35 mph and 7 mph. So this means we can handle 4000 watts at 35 mph and only 1900 watts at 7 mph. At zero speed the maximum power is 500 watts, so it rises from there to 2kw at about 10 mph. Of course with a 29'er these numbers are all reduced a bunch. They are also steady-state, accelerating will lower efficiency quite a bit, so you can't do it too often or the heat will build up. Indeed, if you accelerate then cruise, you really should not cruise at 4000 watts since you need to allow some margin for recovery from the earlier acceleration.

To summarize, perhaps the 3000 watt value printed on the motor is a really good value to use for continuous running at good speed. Use the 4kw feature for "turbo speed" mode, and exceed 4kw only briefly as a "risky event". Derate it to 1500 watts at 10 mph and 400 watts at zero speed. Exceed these values only short-term.

Alan, you can't use the version in Justin's simulator, it's not close to reality until he updates it with the data I sent him. It's WAY to optimistic on efficiency, it says that at WOT on my bike I'd only draw 50A at 55mph on a mountain bike when the reality is in a full tuck I'm drawing about 60-65A at 57MPH at 100% throttle and that goes to about 75A if I sit up. Use the simulator links I posted in the 1st post of this thread if you want to simulate this motor, it's almost identical to what I get on my bike.

I just sent him a PM asking if he would update his simulator with the data points I sent that he asked me for.

[methods]

History shows that every time we bring a new motor to market someone manages to break the first one and there is always a big fuss while we sort it out. That is just the name of the game. Nobody needs to panic - it wont be long before we have a good understanding of the motors limitations.

So far I have not heard any rock solid scientific evidence that "damage" has occurred. It may turn out that in 2 weeks we are all taking blowtorches to our magnet rings... I have seen weirder things happen. Lets let Zombiess get some testing on the hub and reserve judgement.

Zombiess - super good business move to eat his loss and take care of him. My suspicion is that you will be perfectly happy with the returned motor - maybe happier. You have certainly earned my respect as I know exactly what it means to eat thousands of dollars at the worst possible time. That is what you have to do tho and in the end it always pays off to be gracious and not greedy. I will remember that move.

What John said is right too... we can blow any hub in any rim with any controller. Riding style is everything. I am all about making as much power as possible available...... and then using it judiciously. I have 8x8 9C hubs that I have just hammered with 7kw for years that are still riding fine. I also have a pile of 5305 Crystalytes with twisted axles, smashed windings, burnt up windings, broken covers, you name it.

-methods

[nicobie]

Zombiess - super good business move to eat his loss and take care of him. My suspicion is that you will be perfectly happy with the returned motor - maybe happier. You have certainly earned my respect as I know exactly what it means to eat thousands of dollars at the worst possible time. That is what you have to do tho and in the end it always pays off to be gracious and not greedy. I will remember that move.

-methods

As I will too. It is rough being a distributor. Justin and now -methods are doing it both ways.. Manufacturing and supporting their product, and distributing other ebike stuff in order to make a living. If possible try to support them.

[MadRhino]

Hehe... If you give that kind of guarantee, I will buy a few more right now.
I have fried a lot of Ebike stuff and never considered anyone else than myself responsible.

My Cro-motor have seen well over 10Kw a few times in its first testride at 100v hot and 150A batt current
I held it WOT up a 2.5 Km 10% hill road and it took it cool, then did a few short hard steep climbs in the trails that got it hot
It had almost enough time to cool while riding moderately back home 5 Km down the muddy trails, it was still a bit warm
I wanted to feel its power, and start to guess the limits.
It is quick to heat, because of the power to weight ratio, but definitely an exciting motor.

I'm not in a hurry to ride it everyday, I have too many motors and bikes already.
I will probably make a custom job with this one
Long axle for it to fit the 200mm dropouts of my Fatboy, with big bearings to run a cooling line inside
Custom covers to make it fancy, and flange adapters to lace the big 6 in wide, star pattern 20 spoke rim

For comparison: It is faster than my 5404 on the same bike and setup, has about the same torque but pulls more Amps on a start
I can feel the lighter weight of the rear wheel, big difference with the 5404.

It will go on this bike, with a heavily upgraded 24 fet 4110 controller and 2 Kwh of Lipo

[zombiess]

Hillsofvalp told me he just remeasured the kv around 8.0kv now. He was measuring the kv using 119% throttle and is calculating rpm from wheel speed I think. I'll let him explain the rest. I'm not really sure what is up with his motor if anything. I'm thinking maybe we should start a new thread to help him troubleshoot.

Do we have a basic guide on setting up controllers on here anywhere? I'm starting to get a bunch of pm's (because I've written a lot about controllers ) from people who are running big controllers like 24fet sized on 24s lipo and then have over heating issues since they limit the current so much. I don't have the time to reply to them all or write a comprehensive guide on how to pick settings and proper battery voltage. Many are not my customers, but this is something the forum needs with all the new guys buying stuff without fully understanding what they are doing.

[hillzofvalp]

THere is something iffy going on.. when I first tested I did not reach "full speed" at 100%. When I took it to 115% (correction) I could get it up a bit more....


..... just click on my thread below to talk about it more. 100% throttle setting actual speed but NO LOAD is actually what I'm topping out at with the 115% setting. I am still investigating the issue, if one even exists. Might've been a hard day (I can't even remember when this happened even though it was so recent) and maybe the motor wasn't cooling down between charges so it got sluggish. At this point, let's keep this stuff in my own thread and I will post here once I have a more definitive answer.

Mod edit: Thread here: http://endless-sphere.com/forums/viewtopic.php?f=3&t=32037&start=105

[Olly3012]

Top idea

[scriewy]

MUHa hahahaha............ looks like zombiess pinned down, i think the time is nearing for you to become a zombie, but remember what happens in vegas, stays in vegas, from your reply in the 24/36 fet thread sounded like you're under pressure & tense, took my post too seriously


anyways, you tell'm the basic, in a 24s lipo for total load rider /bike /cargo if it's over 110kg and in 26' the motor will get hurt if used around 100a continues over 1.5 minutes on the flats, advised to pull battery amps around 50-60a continues on flats till you/the professional MAD guys here find this motor limits.

riding manners for big bone people:
if conditions are long flat rides and between stop & go at least 4 min, then you can WOT from start accelerate to speed that'l draw 50a and hang there, ontop of 50a speed maybe few occasional WOTs for 10 sec each just for fun

if in frequent stop and go around 1.5-2 min you can WOT each time for 10 sec if desired continues speed will draw around 30a, if desired continues speed in those stops & goes is drawing 50a don't WOT, accelerate slow 7-10s 0-20mph, and if you still want some WOTs do them only after reaching 20mph, WOT duration 10-15 sec till desired continues speed draws 50a.

this is with safety margin, if YOU people gonna hump some hills, simply lower all the continues amp limits and WOT durations from the basics i scribbled.

if wheel smaller than 26', the more fun you can have, if your total weight is under 90kg equals more fun

install BBQ temps inside, very useful, you'l see how fast your system reaches it's limit, after a month with thermometer you could feel the limits blindfolded

edit: ohh i forgot there are 2 groups, i was talking to those looking at CA or any type of wattmeters, to limit your self visually with the throttle, if you dont have any of those and think about programing your controllers then limit batt amps to 70a and keep the phase ration what ever it is now, on the safe side of the motor till people find limits.
if your settings are 100a batt 250a phase, 70a bat be on phase 175a, kapish ?

[Samd]

Madrhino that would be awesome. I think you'll need reobar to replace those spokes though

[John in CR]

There's nothing wrong with HillsOfAlp's motor. His Kv is correct. A Kv with any speed setting other than 100% and WOT is invalid. He's just doing stuff with invalid speed settings and no telling what else in the program settings. Now it sounds like he's expecting to be able to achieve no load rpm while riding his bike, so he needs to apologize to all, and spend a lot less time typing and more time reading, experimenting, learning and riding.

[LarsE]

Is the a way to by these motors for Europe buyers without shipping them twice over the atlantic ocean (you get them from Croatia, right)?

[zombiess]

Is the a way to by these motors for Europe buyers without shipping them twice over the atlantic ocean (you get them from Croatia, right)?

Contact Accountant directly, he handles all sales to Europe.

[hillzofvalp]

Motor is fine, all. I apologize for the mix up and naivety. Theres always more to learn in his hobby.

To those interested in buying, do not hesitate at the slightest. I think this motor is fine in a 29 inch wheel.. Yes less than ideal but plenty powerful (only at 4.3kW 77/145A). I get it up to 107C after a long ride (with the correct controller parameters!). As long as you aren't an idiot around hills, and you don't sit at stop lights too long, it's verydifficult to notice any drop in power.

With that said, I'm going to put it into a smaller wheel when time allows, but I'd first like to get it up to 85V and implement water cooling. I will try my best to get a solid ride video in as is at my current power level, but all I have is an iPhone.

[hillzofvalp]

Not what I call a great video, but at least we've moved out of the parking garage. I need to somehow fixate my phone on my helmet.. or handlebars.

[scriewy]

hilzOFrelax can you measure the angle of that hill, looks like 5-6 degrees, that's a toughy.
you can use ruler and do sin or cos on that little wall at 0:51, if you have a calculator that has those functions.

in my calcs i got 5.73 degrees.

[hillzofvalp]

I'll check it out sometime soon.

I am addicted to power now. I need to take it up to 8kW. Liquid cooling. 25S A123 M1. I was just using the calculator and found that I could achieve 0-25mph times of about 2.5-3.0 seconds in a 26" wheel... 0-45 in 7-9 seconds. This motor is going to make me crazy.

[hillzofvalp]

Your estimate is close.. My iPhone gyro measured 5.5-6.0 but only over 100mm of surface at a couple different places. The neighboring hill which I haven't gone up yet is longer and 6.5 degrees....

After more riding I'm finding that if I don't gun it when I realllllllly DO NOT need to be gunning it, the motor doesn't get above 100C. I've also been trying to pedal hard under 5mph and that seems to help. I am hoping that anyone interested in water cooling the beast for 7-8kW will share their advice in my build thread.

[Marfa]

Hello,

I am interested in purchasing on of these hub motors.

Can you tell me more about the process and if possible send me a land-line number to call.

Also, please reply to me email address listed below.

Thanks,

Neil L Chavigny
432 386 0689
chavigny@sbcglobal.net

[fractal]

Hello,

I am interested in purchasing on of these hub motors.

Can you tell me more about the process and if possible send me a land-line number to call.

Also, please reply to me email address listed below.

Thanks,

Neil L Chavigny
432 386 0689
chavigny@sbcglobal.net

go to page 1 of this thread

[CAP3r5]

Hello all,
This is actually my first post on this site. I've been reading it now for about 2 weeks just to get a better idea of what I am getting in to. I am looking to make my first ebike with a hubzilla motor and a lyen controller (go hard or go home!). The only problem is that I am worried about how I am going to get this monster to fit in the dropout. I am looking to get a good deal on a bike and have been searching craigslist for a good bike for my first project. I've found a few possibilities:
http://columbus.craigslist.org/bik/3024093955.html
http://pittsburgh.craigslist.org/bik/3074106672.html
or even this one (but I'm not sure if I can add disc brakes to the rear wheel):
http://www.walmart.com/ip/Titan-Glacier ... ct+Reviews

I am trying to find a bike with smaller wheels with no luck so far, but I don't think 26" should be a problem with this bike as I would mostly be using it in Columbus, Oh where it's basically flat everywhere. I was wondering what it takes to modify those bikes and get this motor to fit in the dropout. Any advice or tips on choosing the frame for this motor would be helpful. I read that it is not recommended to widen aluminum based dropouts more than a few mm so I'm wondering if it's even possible.

Thanks in advance for any help!

Cullen

[methods]

Get a steel frame
File the drops to fit the 16mm axle (deeper, not wider)
Work out your Torque arm solution
Use a car jack (scissor jack) to spread the drops.

When you spread them you will need to go further than you want because they will settle. Stretching to 170mm may result in the frame resting at 140mm... or stretching to 200mm may result in the frame resting at 150. I used to only bend the frame dynamically and slip the motor in there such that it would "snap back" once the hub was removed. Yea... that sounds great until you are on your knees on a trail someplace trying to replace a rear tire.

Pay attention to symmetry as it will want to bend unevenly.

For the record... You may want to start out with a little less motor and controller... make your mistakes with some cheaper equipment... but I understand the desire to go big or go home. JUST MAKE SURE YOU BUILD UP PROPER TORQUE ARMS. Dont make me waste my breath....

-methods

[hillzofvalp]

especially depending on your power level.. the cromotor is a beast. I am glad that my steel dropouts failed with the 9C before dropping in the cromotor.

[methods]

especially depending on your power level.. the cromotor is a beast. I am glad that my steel dropouts failed with the 9C before dropping in the cromotor.

Drop failure should not be an issue with proper torque arming. I would use wooden drops.

The torque arm holds the motor, not the drops. I see the drops as just an alignment device.

-methods

[John in CR]

Cullen,

Welcome to the revolution. Don't worry about finding a bike with smaller wheels. Those will typically be for kids. A full size bike is fine for running a smaller wheel for the motor on the back, and the resulting change in geometry typically affects handling in a positive way at speed because it increase trail.

+1 regarding good torque arms, though my warning is stronger. They are absolutely mandatory, especially with a high power high torque motor like the Cromotor Hubzilla. The entire force to move a hubmotored ebike is transferred by the motor's axle trying to spin in the dropouts, and due to the very small radius that force is literally thousands of pounds. If you're lucky a failure is only the axle spinning in the dropouts and twisting and breaking the motor wire harness, which is a pain in the butt to change. Another form of failure is catastrophic where the spinning axle climbs out of the dropouts suddenly leaving the wheel no longer attached to the bike, often ruining the dropout in the process and in the case of AL frames snapping it right off. Don't even be tempted to test ride it without good torque arms installed.

Learn from the hard lessons of others in this regard and get that big EV grin with piece of mind.

John

[CAP3r5]

Yeah I figured I would probably need some good torque arms with such a powerful motor... I really did not think about how much force is applied to such a small area thanks for reiterating that! I guess for torque arms it's go hard or don't make it home...

I figured out my host bike for my project:
http://www.wsports.com/img/prods/large/ ... 0_bike.jpg

It is made of aluminum except for the dropout which is made of steel. I found it brand new on craigslist and am trying to get it for under $250 which I think is a really good deal. I think that it should be able to handle the hubzilla after I carefully widen the dropout. But if anyone see's why these two should not be wed speak now or forever hold your peace.

Cullen