How To, 50A BBSHD Controller Mod

[mich031m]

This old BBSHD controller is fulfilled. It is my fourth tuned controller and it got the full overhaul. Tuned to the max and ready for 22S 92V 55A.
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It will be an absolute beast and probably the most insane BBSHD with an original controller .

I somewhat expect the motor axle to snap but it doesn't matter. It was a journey to get there. Will I do another FET job? Hell no it took six hours.


All mods done:
- Vdrop of approx 30V on brown wire using LEDs. The controller allows and displays up to 61.4 V on dpc18 display.

- Shunt mod 60A using two extra 5 mOhm resistors.

- Caps replaced with 100V models, 1700uF in all inside controller. I might add an extra outside controller.

- Mosfets NF75NF replaced with IRFB4110.
from: DKK 37.26 | 10PCS-50PCS IRFB4110PBF TO220 IRFB4110 B4110 TO-220 MOS FET transistor Original disassembly

https://a.aliexpress.com/_m060L2t

- Stator/housing sides creamed with cooling paste (a real mess to do and a pain to reseat the axle and end bearing).

- Thermistor NTC 10kOhm from laptop battery pack inserted into stator windings, ready for external readout.

- All important traces on controller beefed up with copper wire.

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Did you repot the controller or is it not neccesary? I was also wondering it you just changed the 2 caps and for what values. i can see a 1000 uf. is the other 220 uf?

 

[yantra yatra]

I’d be interested to know if you could do this with the new torque sensing BBSHD M635. At least the shunt mod but also higher voltage. Would prob make the torque sensing settings a bit complicated

 

[sysrq]

I wouldn't say just for overvolting, more so over amping. Running higher voltage like 72v means you need less amps for the same wattage so less heat which is what causes the peanut butter failure. I would say the shunt mod controllers are the most likely to experience it, lower voltage with double the amps, stock inefficient bafang controller, no proper thermal throttling. But also from what I've heard easiest way to wreck the gear is to stick the bike in a really small cog in the rear and hammer the throttle from a stop.

I've been running my aftermarket controller at 52V and 65A on the stock gear for a year now still strong, and I believe it's because of the reasons I listed above

What about hammering the throttle on a 17% hill with 130kg system weight in 40t:51t gear with 7°C ambient temperature and cold motor?

 

[Bengy22]

What about hammering the throttle on a 17% hill with 130kg system weight in 40t:51t gear with 7°C ambient temperature and cold motor?

For which setup are you asking about, stock controller shunt modded, aftermarket controller, or aftermarket 72v? Either way though with it geared that low I don't think you would have any problems with any of those though. Putting that into the Grin simulator though with a 50A shunt mod you would be fine temps wise, although you wouldn't be breaking any speed records at 9mph though.

But since that comment was made I've gone to a 72v battery and its a huge difference in power and temps, I run now 50% more peak power and temps never even get close to what they did on 52v. Thermal throttling almost every ride vs a handful of times in 1.5k miles

 

[sysrq]

For which setup are you asking about, stock controller shunt modded, aftermarket controller, or aftermarket 72v? Either way though with it geared that low I don't think you would have any problems with any of those though. Putting that into the Grin simulator though with a 50A shunt mod you would be fine temps wise, although you wouldn't be breaking any speed records at 9mph though.

But since that comment was made I've gone to a 72v battery and its a huge difference in power and temps, I run now 50% more peak power and temps never even get close to what they did on 52v. Thermal throttling almost every ride vs a handful of times in 1.5k miles

Talking about stock controller and 52V battery. Since hammering the throttle on a 17% hill with gear that low results in wheelies then then the peak load on the nylon gear resulting in damage might be reduced since it does slightly less work by lifting the front of the bike up compared to pulling the weight up the hill?

 

[Bengy22]

Talking about stock controller and 52V battery. Since hammering the throttle on a 17% hill with gear that low results in wheelies then then the peak load on the nylon gear resulting in damage might be reduced since it does slightly less work by lifting the front of the bike up compared to pulling the weight up the hill?

I'm not sure about if wheelieing requires less work than going up the hill, but with the bike geared that low even going up a steep incline like that your only worry would be the motor overheating. Which I guess depends on how long the hill goes for but I don't believe you will have issues with that gearing going that slow and with those ambient temps