Metallover's 9c Blackcomb Build

[johnrobholmes]

Did you bump up your phase current too? Maybe increase the block timing if you want better acceleration.

 

[dnmun]

when you drilled the cover, did you drill from the inside and center the holes between the ribs?

maybe there is someone who can run a structural analysis program on the cover with holes drilled out, how to orient them to minimize loss of strength and maybe reconsider the idea of using one large hole versus say 3 smaller holes with one closer to the center and two on the outer edge of the cover in that radius-ed section, or even maybe make a small stencil and mark a section oriented between the ribs in a more trapezoidal section, on the outside between the ribs, then dremel out around the perimeter of that stencil.

maybe then the centrifugal force of the air entrained by the rotating cover would raise the lateral flow rate across the edge of the stator. maybe even add some little ribs of aluminum attached to the steel part of the stator under the winding with J-B Weld would force the air to flow radially across the stator sides. make sure you coat the hall sensors with a buncha sealant like rtv or silicone rubber.

 

[Metallover]

These are my current settings - Ihave my phase current at 2.5x the rated current.

I'll try maxing out the block time...


When I drilled my holes I drilled from the inside. I made a template out of a baseball card that fit in between the ribs and I marked my holes with that.

I'll coat my halls,,, Never thought of doing that.

 

[johnrobholmes]

Bump the block time slowly. Try 5 or 7 first.

 

[Metallover]

Bump the block time slowly. Try 5 or 7 first.

Will do. Batteries are still charging and rain is threatening so I won't get to ride it for awhile..

I am playing around with a fan... 12vdc fan on 6s lipo inside the motor sound good to you?

 

[johnrobholmes]

That would work pretty well I think, assuming you didn't fry the fan. Do you have vents on the other case side too? You could have one angled as inlets, and the others as outlets.

 

[Metallover]

I just got back inside from lots of testing. I ended up putting the fan inside the motor and running it off of one 6s lipo. It was pretty loud and it didn't burn up! The exciting thing is that I had LOTS of trouble trying to get the motor up to the 95*C buzzer. I blasted though town at 35+mph, went up a mega hill maintaining 32mph, and only near the end of my ride did the buzzer go off.

I improved my top speed! With the 3-speed switch settings, I set one to 120%. I was able to go from about 38mph to 41mph on a smooth flat road. I also beat my speed record; Now it's 46.9! I was going down my mega hill..

I played with the block settings for awhile and I really didn't feel a difference. It's at 10 right now, but I think I'll change it back down to 4 or 5 because that is what I've seen other people using.

I tried to get more power constantly, and I ended up with only 31.51a and 2133w. The bike felt faster then before but it wasn't anything amazing. I did this by raising the max current from 40a to 57a. Both the phase current and rated current are maxed out. If anyone is running a 9c and making over 2500w, please let me know what settings you are running. A screenshot would be great. This is what I have ATM

I took some more pictures too

Here is how I have my fan. It's a 12v fan overvolted to about 24v.

I couldn't fit the wires through the axle, so I dremeled a small slot in the axle and made the wires come out crystalyte style. 8)

Here's a shot of the other side of the motor. JRH, please explain to me what you mean,, Should I attach cooling fins to my motor?

And I'm open for compliments on my clean wiring!

One problem I may have is a little rear axle play. When I hit the regen I can feel the axle shift. Maybe I should try to shim my torque arms a little more?

 

[johnrobholmes]

The jacking you feel may be play in the shock mount.

Make one side have all externally scooping holes, put a little angle to them. Then the other should be venting holes, reverse angled to scoop from the inside. It should pull air through the motor in one direction when it spools up. Basically, make the side covers like fan blades.

 

[mwkeefer]

Metallover,

You asked...

I have tested both the front and rear FH205 and RH205 respectively in 26" and 20" mode running 18S packs on 9 FET IRFB4110 modded controllers with 2x shunts (stock) in place for default 44A current limit, then programmed with EB812 to allow a slightly higher than 35A peak (secondary Limit)...

For my currents I have:
Primary: 40A (actual draw is 83A maximum)
Phase: 55A (actual should be 110A in theory)
Pack Nominal Voltage (18S): 66.6v
Nominal Peak power: 5525w or 7.3704 HP.

This runs fine with stock 9C but I will admit, I don't ride them this way... just wanted to test the limits.

That said, by running 2X or more the Phase Current - you lower your maximum top end speed because Phase Voltage is lowered to create Phase Current Multiplication... understand?

The only benefit to running BT higher, is for low speed or no speed raw accelleration... it should under maximum load enable more current for a very short time... when you have your Phase currents so high already and assuming you could acheive even a 30A boost for 8 seconds (that's the idea) then you would likely toast your phases (even the upgraded ones).

Best bet... set block time to 1, tweak your phase current to be a lower multiple of the primary current (try 1.5x for instance or 1:1 if you want to see true MAXIMUM TOP END)... when you have the top speed you want while you and all your weight are onboard (this means sufficient power to acheive max velocity) then you just bump that to 4 or 8 or whatever, the purpose is to give you less limiting for more low end launchign torque... once your moving it's like a passing burst, that is if your motor is capable of using the additional current.

Sorry if this was more than you asked for but I figured I'd dump it on ya... my Metallica shirts (short sleeve) are in the Wash (had one on yesterday, St Anger... I know please don't laugh!)...

OT: There really is nothing like Fire with Fire while playing slalom racer with traffic at 35-40mph on an ebike = )_ It's like bliss, S&M (katulu) is fantastic for night rides down long windy roads.

-Mike

 

[Metallover]

What material should I use? What adhesive should I use to attach them?

A powerade cap fits over the holes, maybe I could modify them to scoop more air...

 

[Metallover]

Thanks for the info Mike! So after I get my rated current to phase current dialed in, then change the block time?

 

[mwkeefer]

Yes basically... I realize the process for this isn't defined and it's more complicated than
downgrading and jailbreaking an iPhone in linux - just a lot of steps to be done in the proper order to correctly "tune" or dial in when you don't have all the various specs (true no load kv of motor without multiplication of current, torque constants, etc) and none of us have them all! Actually in speaking with manufacturer I think they don't even know all of it {seriously}

I know I should do a full build and document it and the dialin process, Im actually beginning to get photos and video of howto repair and enhance controllers {inspired by thud} but then it will be the controller for a rebuild and tune or dial in of my dahon Jack. I will do a 9c to follow, hopefully in time for the new ones with thinner axles (whoops not sure I'm supposed to mention those yet).

Hope that helps!

PM me if u have real time questions on doing any of this...

-Mike

 

[Metallover]

Well, these are the settings I ended up with. I tried your method Mike, but it was really slow accelerating at 1x and 1.5x phase current. It accelerates very fast at this setting. I pulled a max of 26.43a and I made 1922w. This is respectable, but I still want more.

During testing, I looked at my watt meter and it said I pulled 39a and 2750w! At the same time I noticed that one of the six lipos had come unplugged. It was the pack paralleled with the pack I had my watt meter on. If someone can explain this please go ahead.

And here is a shot of my bike at the top of a hill. This is in a state park. Usually my motor will overheat and I need to slow down and stop. With the cooling holes and fan, I went up the hill faster than I ever have and I never needed to stop.

I have looked at a lot of threads, and I have seen people beef up their traces and shunts. Would those mods give me more power? Would they un-calibrate the software?

 

[grindz145]

Beefing up the shunt resistor will essentially 'uncallibrate' the software, in order to fool it into thinking LESS current is actually flowing so that the actual current limit is higher. beefing up the traces certainly can't hurt (unless you hurt something else in the process). Both of these will give you more usable power out of the controller, but you have to be careful with the shunt... it is precise and if you effectively remove the current limit by lowering the shunt resistance too far, you can run the risk of burning up the controller.

I'm really impressed with all the work you've done, very nice!

 

[Hyena]

Why is your speed limit set to 35 and 50? I'd be bumping that up to 99 and seeing if that makes any difference.
Failing that it's probably your shunt. Is it a lyen 12 fet controller that's supposed to be a higher powered one ? Add another shunt or solder a few fine strands of copper across it and your current should jump alot.

I'm surprised you're managing to heat it up so much with those big holes and only 30 odd amps. Something doesn't sound right...
Your holes are also bordering on too big, I'd be a bit worried about them being able to take the load if you're doing alot of hard offroading...

 

[Metallover]

I have my current limits set to 35 and 50 for if I want to ride efficiently. I usually have it at 100 or 120 if I'm doing performance stuff.

My controller is an ecrazyman controller.. I'll look into soldering the shunt. I think I'm going to get a CA soon and I'll have to open the controller up to install it as it is a DP model.

Crazy thought, but maybe I'm actually making more power... I have my pack in a 3s2p configuration. My turnigy watt meter is hooked up to one pack. Maybe instad of pulling, say 26a, I am actually pulling 52a?................. no that's stupid. It showed 20a before before I programmed it and it had a default 20a limit (I think).... :| :| :| :| :|

When I am test riding I gun it to like 35mph then slow to about 10 with regen the gun it again. When I'm not slowing down I'm offroading WOT most of the time. Going up big, bumpy, grass hills. I ride it really hard. Probably hard enough to heat it up?

If I solder the shunt I'll keep a close eye on the controller

Thanks for the advice Grindz and Hyena...

 

[mwkeefer]

One pack series or one pack parallel? (near a trick question)...

But say for instance you had isolated one Parallel part and connected to that.. You would be measuring the current passing through... If 3P and of equal capacity / C rate, then it would be displaying 1/3 of your total current.. understand?

I am assuming your setup is actually 3P2S right? And your monitoring a block of 3P but not both packs in the series (I assume for voltage contraints right?)...

If that is correct, then your current is accurate but your Power isnt...

If your measuring at 1/2 total pack voltage ... let's make it easy and say 25v each Series Portion for a Combined voltage of 50v.

If the meter is showing 30A, and 750 watts... in reality, you are producing 1500w output...

For 50A the meter will say your producing (again at 25v part) 1250 watts but really it's 2500 watts since the voltage potential is 2x that of what is seen by the meter...

If for some unknown reason... you had connected a single Parallel Portion of a Single Series Block (not even sure how this would be possible... yes I am but.), then assuming the above numbers and 3P... your meter would show for instance 25A and 625 watts produced...

In this case... the meter is diplaying the current through the single parallel chunk of the single series block (I hope this makes more sense)... so for 3P, and assuming identical voltages / potentials... this would indicate that each parallel block was being asked about 25A so now we are really seeing 75A primary current and don't forget,,, redo your watts math based on the true current and the entire series pack voltage so in our example.... 75A * 25V * 2 = 3750 Watts Peak...

And don't forget the phase multiplication factor, if your at 2.5... then you could be pushing (from the example data) as little as 65 A or as much as 187.50 Amps Phase Current...

Someone will follow this up telling me the whole second half (after explaining the series measurement power, etc) it all BS and will never happen in the real world...

I've used the method for determining if a pack was being asked the same current... So I built up in series first... then monitored a single Series P (15S) of a 3P at a time.. turns out the battery I thought was weaker (running out faster) was the stronger and was producing nearly 10% more power than it's 2 cousins... that was IR not connector loss too!

I appologize for even suggesting the 1.5X Phase current, idiot that I am ... I forgot totally your on a Direct Drive... Some geared motors have so much low end torque for 2-3 seconds while the spool up that there is really no need for the phase multiplication and for instance on a 20"... well, 1.5 works great for me (at 60v and 70A).

Hope this helps!
-Mike

 

[Metallover]

This is how I have my packs set up. I would hook the watt meter up to the entire pack, but I don't think it can handle a fresh 75v, can it?

If the watt meter reads 26a, 1900w,, Does that mean that I am pulling 26a and 3800w throughout the entire pack?

 

[Hyena]

OK yeah taht's not a good way to do it. I have mine set on my Norco to only measure one 6S group and as Mike said it makes your power and voltage inaccurate but most importantly (to me) the current and Ah IS correct (and I multiply wattage and voltage x 3 for true pack values) Mind you that's a 6S2P group - you're only looking at one individual pack the way you have it set up there.
You need to wire it like this:

 

[Metallover]

I have been multiplying the wattage by 3 to get the total power.. Do I need to multiply that by two? Ehh, I'll do a little soldering work and then I'll see what data the lil thing puts out.... Or maybe I'll just wait until I get my CA...

 

[johnrobholmes]

The amperage is off by a factor of two. You will need to monitor the overall pack voltage in a different way, or loosely multiply by three. So you may be running six times the power that you think you are :lol:

 

[dbaker]

You should share some more details about the fans in your motor. I think this is the first 9C fan cooling set up!

 

[mwkeefer]

Which meter is that? The Turnigy Branded, back lit units work on 18S hot (70v+) but... I smoked a watts up, though I think perhaps it was on 20S and not 18.

To calculate AH used (you do have cell monitoring right?) it would be AmpHours * 3 (as you have it hooked in your diagram) - when connecting the entire 6S subpack part - don't multiply by 3 as you are already getting the right Current now just multiply the voltage * 3 and then the current and voltage together to get true watts..

Based on your diagram, yep your pulling

18S Hot Maximum is 75.6v - I only charge to 4.16/4.18 depending but I've never had issues with the Turnigy Watt Meters at 18S.

Oh and they only ever show 66.4v maximum - maybe time for a CA or another Watt Meter... monitor 12S2P with one and 6S2P with the other... you will get real fast at adding big numbers in your head while riding

Hope it helps!
Mike

 

[Hyena]

To calculate AH used (you do have cell monitoring right?) it would be AmpHours * 3 (as you have it hooked in your diagram)

Actually the way he has it hooked now would probably be ah * 2 although I'm not sure how totally accurate it'd be.
If he wires it like I showed above his Ah will be correct but the voltage and wattage will only correspond to 1 6S bank.
You dont really need to see the whole pack voltage anyway, as you said as long as you have some sort of cell level protection/warning monitoring a single 6S sub pack is fine - the current is accurate, the Ah is accurate and you get used to basing your usage and approximating distance to LVC looking at 6S voltages (assuming you just glance down and don't look for the ah reading )

 

[Metallover]

I held my breath and hooked up my turnigy watt meter up to my entier 18s pack....


Then I went for a ride....



....

When I had my watt meter hooked up to just one pack, the meter read 640.9w. I multiplied it by 3 and got 1922w. I should have multiplied it by 6 and I would have gotten 3884w.