Much More Powerful Pie Now!!!

[GM Canada]

I remember when Leslie did the shunt modification on his two pies. After doing the mod he used the USB cable to pull back the amps to a desireable level. this seemed to work. For him for quite a while. I had heard that one of the controllers failed(I think he drilled a hole through the board by mistake) but the other still goes strong.

It would be interesting if someone would take on the challenge of adding small gauge wires to the shunt in increments. Then using a cycle analyst or something could see what gauge of wire adds how many amps.

Gary

[JS]

I haven't noticed much heating after this mod. It's handwarm at most. No idea about the temperature inside the Pie.

My driving is normal city driving, to work and back home mostly, only 4km one way with some long uphills on the way, which are pure agony on normal bicycle. I only need to accelerate about 3 seconds to get to 30km/h and it shouldn't stress the Pie too much. I bet there would be overheating if I used it on a hilly forest path or something.

Other changes: changed the voltage setting back to 48V from 24V, installed 80A fuse and added a torque arm (10mm wrench + hose clamp) 

I'm very happy with the motor now. For next summer I need to get a more comfortable bike, with full suspension probably.

And I'm interested in that 2kW motor scorpion mentioned. Pie is a bit too large and gets too much attention (in a few days I got 4-6 people wanting me to build them electric bikes too...) Find me a 2kW mini motor and I'm buying it!

[Bikemad]

You should probably buy an egg timer too, so you can measure how long it lasts hehe

Good work on the mod, is your bike making wheelies now?

I thought the same about mine, but the original controller is still going strong.

Replaced my blown hall sensors last night, so I decided to take the bike for a 7 mile ride today with some very steep hills.

My 26" Pie certainly pulls wheelies when accelerating up hills (without pedalling) and I no longer need to use my gears, as I can now pull away in top gear because the throttle now works from stationary again.

The power has increased very slightly compared to sensorless mode, but the motor does sound noticeably quieter now. 

Here are the stats from my ride earlier today:

14 cell 5Ah LiPo pack was 58.6V at start of trip.

Maximum Amps:   60.35Amps      (58.63Amps Sensorless)
Maximum Power:  3108.2Watts  (3039.9Watts Sensorless)
Minimum Voltage: 47.42V          (48.14V Sensorless)
Resting Voltage:  52.57V
Average Speed:  19.19mph
Maximum Speed:  34.60mph (downhill)

My average speed would have been higher, but I rode slower on the main road because my legs could not keep up with the pedals, and I did not want to draw attention to my speed.

I almost got run off the road at one point when a car pulled over onto the cycle lane to allow a motorbike to pass, just as I was about to ride past him on the inside! I really could have done with some air horns like Monkey has, but at least my brakes (and reactions) worked well.

It's definitely the tamed 700-800W version. Just a few hundred watts more might do it.
Battery is 48V LiFePo4 2C, so there's plenty of power available for the Pie.

Judging by the thickness of your shunt bypass wire, I expect you now have a few thousand watts more!

I'm glad you've added a torque arm, I keep meaning to fabricate something for mine but I'm currently still relying on steel dropouts and some very tight axle nuts.

Alan
 

[JS]

You need to fabricate a torque arm?



Even though I have a thick bypass wire, the software amp limits still apply, right? Well... mine are still set to 30/50 

[Who42]

Hear are some pics of the older untamed Controller and Newer Tamed Controller:

[Who42]

 MY SUPER CRUISE CONTROLLER  
I resurrected this early internal cruise controller it had blown the mosfets I replaced them with STP140NF75 / 75v / 120amp / 150deg    Then I put it in an external case after moving the caps etc around  to fit
Then mounted the whole thing on a really big heat sink after drilling a small hole to let the boost wires through
Then I added a BOOST BUTTON so I could have both normal and BOOST mode   Cruise and Power  I can choose either  
I used silver solder to beef up all high current joints , reattaching all connectors and to solder mosfets in place  

You can really feel the difference especially up hills  
So far it only gets slightly warm at well over 1000w

[Who42]

MY SUPER CRUISE CONTROLLER  

Then I mounted the whole thing in a ALLOY box with the heat sink on the outside

I may even put a relay inside the alloy controller box and remote control the boost button from handlebars

[JS]

Hmmm, got an idea from that light switch button. That could be used as a boost switch with a ordinary car relay!

Bike could be a street legal 250W with pedelec sensor and perhaps narrowed down shunt to keep the power down even though the software has high amp limits.
Push the button and relay engages the bypass shunt and disconnects the pedelec sensor 

I wish someone would have time to test the effects of different shunt wire thicknesses.

[JS]

Ok, my Pie just died. What was that about the egg timer?

Might be the BMS too though. It doesn't seem to let any power through.

Lost power after a long uphill climb, lights out and that was it.

Any easy ways to troubleshoot the motor+controller? I guess I'll try ruling out the bms by trying with 2 car batteries first.

[Who42]

If you have blown the mosfets I would replace them with STP140NF75 / 75v / 120amp / 150deg.    Then put it in an alloy box with a large heat sink like I did  

[JS]

It's an internal controller, so large heatsink needs some work... but I'll definitely consider those mosfets.

Anyway, troubleshooting is done and everything seems to point to the BMS.

I bypassed the BMS and ran tests with 24V and 48V and all the power is still there. That would not be the case if there was anything broken inside the Pie?

BMS itself is quite simple by structure. Would it help if I posted a picture of it here? I did some measuring with it and everything seemed fine. Every mosfet had 50V on two legs and -14V on one leg and all the leads coming from battery showed consistent 3.3V rise in each wire.

Main question: Can I just bypass the BMS? Of course I'd protect the battery with smaller fuse and take care I don't run it empty (not a problem with my short commutes).

Edit: I guess BMS is still quite necessary for charging. Need to test if it still works that way.

[MonkeyMagic]

What battery are you using?

If its the GM battery in the aluminium casing. then the BMS is rated for around 60A peak MAX regardless of the voltage type.

The cells are 26650 are rated at 10A max continous, 20A peak (<3 seconds) so if you went up a big hill yes you could have toasted one of the Fet's on the BMS or damaged a cell causing the BMS to switch off. I'd probably say the latter

You cannot check cell block 1 of a GM battery without disassembling it, and you cannot test a MOSFET in circuit. So I would still do some trouble shooting before removing the BMS altogether...

It will be fine charging a pack bypassing the BMS, but you should balance the cells every few months. Oh and of course closely monitor the pack so you don't damage any cells!

[JS]

Vpower pack. 15A continuous 30A max. With A123 26650 cells. Ok, might have overstressed it a bit with perhaps 30 second full throttle run.

I measured the pack through the BMS wires again, first cell 3.3V and steady steps up to 49.4V, all identical. Charger says the pack is full and it might be true, only 5min drive after last full charge, so I don't know yet if it charges at all or not.

I don't really care if something breaks. I just don't want the 10kg battery exploding under my ass 

Already moving on: sent an inquiry to cell-man about a high power Mac-motor and one of those high power battery packs 
Or I'll just risk it and go with LiPos. Those scare me though.

[DirtyGinge]

Hi JS

Although the cellman motor is great, the pie is also amazing with an external controller built to handle the power, like the lyen infineons.....coupled with a good controller, no problems at all.......

[JS]

Although the cellman motor is great, the pie is also amazing with an external controller built to handle the power, like the lyen infineons.....coupled with a good controller, no problems at all.......

Anyone converted an internal controller Pie to external? Lots of wires to connect I suppose. Has anyone managed to burn the Pie with an external controller?
I still want to try the Mac too though Smaller size is always a plus, since it gets less attention from authorities.