“Stealth” (No Display Needed) 48/52V BBSHD FOC Controller Upgrade ASI BAC 800 2600W (Peak) Loom


“Stealth” 48/52V BBSHD FOC Controller Upgrade ASI BAC 800 2600W (Peak) Loom



The Stealth Kit is Here!!!!! (No Display Needed)

48/52V BBSHD FOC Controller Upgrade ASI BAC 800 2600W (Peak)  Cover, Loom

This is the fastest 52v BBSHD upgrade solution in the world.

Higher Volts, Higher RPM Higher Speed !

This is truly plug n play and expect RELIABLE speeds of around 40+ MPH

* UK Warranty 

For international orders, please email: [email protected]

Why are we calling this the stealth? Because its almost road legal and does not need a display.

The PAS is set to 250 watts which will assist you down the road, but the throttle is still set at full power!

If you ride the road on this set up with a 250 watt sticker (please ask and we will supply at £2.50) and have your throttle disconnected, you are totally road legal as long as you do not go faster than 15.5 mph under assist> Although you are allowed to ride a bike faster than that, just with assist.! The kit is cheaper as has no display, but you can still use any Bafang display to read your volts etc, its just the PAS level will not be changeable. The controller can not be used past 60V and the bluetooth function is not available. This controller can not be upgraded to 72V (It is physically different to the “full version”.

Did you ever wish your BBSHD went substantially faster, pulled harder and you didn’t have to be told you can’t buy the controller you want – shush it’s a secret?

Well thanks to a very clever friend of ours, we are the UK and EU distributor for this exceptional device.

This controller has everything: field weakening (allowing higher rpm), set maximum amps, set maximum watts, maintain these figures while volts drop, totally plug n play and potted to 100% waterproof.

Advanced processing and state of the art allows it to compute much faster and much more accurately than the standard Bafang unit (or any modded Bafang controller). Imagine your first media phone in comparison to the latest Iphone/Android device? – Things have moved on and these Canadian devices have not been designed with penny pinching mass market sales like the original.  All of this makes your 52 V motor pull much harder and release around 15% more speed than a 50A Bafang controller and whopping 100% more power than the standard, while still using your standard display! (NB, please see our note about displays). We might add the power is designed to come in without the mechanical snapping lurch of an inferior set up.

These controller have been set up so that it can handle anything from 50 A up to 3250W (easily within their design). This might mean a little explaining:

We have tested the BBSHD to destruction and on more than one occasion right up to 4500 Watts and learned a few things, real facts and not the odd exception.

Amps create heat, heat weakens the nylon gear and too many watts snap the pinion. So how do we get around this? Simple, know the limits but don’t get too close. Sure these are now nearer the limit, but ridden correctly (let the motor spin and don’t labour in the wrong gear), a reliable ride can still be had. At the lower volts where big amps are needed, we have capped the limit to 50A but as you increase your volts, we capped the watts to 3250 W. A ludicrous controller at 50A has 2500Watts – so does ours, but now add 10 -15% improvement through field weakening!

Unfortunately not all displays are equal. Bafang released a myriad of display, and different firm wares. We are a small company and haven’t managed to test all of them; but what we have found, is that all the original displays still  show everything (time, speed watts etc), but will not allow PAS or power selection. You can still ride your bike with the standard display on throttle only (please ensure you use low gears when running at full power or ask us to limit the power to 2500watts, we do not recommend continuous full power as it may damage the Nylon gear or Rota shaft. Correct gearing must be used. – We highly recommend ramping power through the use of one of our display)

Bafang displays will only allow full power on throttle and PAS set at road legal 250w

48v -52v (up to 60V) Bafang display (PAS will not work)

The controller is locked to protect our intellectual property

This controller is not capable of higher voltages than 59.9V

We do not charge a fee for general support work (something is not working)

Controller Feature Set

  • FOC (Field Oriented Control)
  • improved torque throughout the rev range
  • Higher RPM compared to the stock controller on 52V and especially on 72V (Up to 7500RPM)
  • Silky smooth throttle control and responsiveness, like a fine adjustable knob on a light switch.
  • Improved efficiency due to FOC algorithm, premium internal components within the controller (like the mosfets) which increases efficiency while reducing heat losses
  • Automatic sensored to sensorless transition which gives you addition 5% top speed and better performance
  • Can use Bafang display for readouts like volts and power, but will not change the power settings which are fixed.
  • Includes 3D Printed Cover
  • Usable voltage is 36V-59.9V
  • Dimensions 81mm x 55mm x 39mm
  • Weight 300 grams

The kit includes:

ASI BAC 800 36V – 59.9V FOC 90A

Wiring loom to connect direct to existing BBSHD loom with Anderson Power connectors

Motor side cover

Free UK

When ordering please supply your wheel size – thank you


Gearing (video tutorial to follow or call for explanation):

Use a 42T front Chain wheel to “Clam Shell the motor and bring the chain line inbound – we sell a cheap Lekkie clone version)

Reduce your rear cassette size to improve the chain line, removing any gears smaller than 15T and create your perfect centre-line around the 26T/28T rear sprocket (depending on wheel size)

Remove the old 9 -10=11 speed cassette and use the gear range from 15T to lowest gear. We love the  Shimano XT CS-M771-10 speed cassette as shown in the photo. Use spacers to give you a perfect chain line for the gear of your choice. For 27.5 and 29er set ups we recommend a 28T rear gear. For 26″ wheels a 26″ T gear. For fat bikes as big as you can get! (32T +)

If you want to be very smart, you can use a 2.35 mm spacer from your old cassette to space out a 17T as a “Get you home” cog for pedaling or PAS assist in power level 1. But you might have to manually put the chain onto the cog. Use your old derailleur as a tensioner and give your self enough chain (we recommend KMC x10e chains) to move up and down  you have. You will want to adjust your max/min screws so the chain does not slip off the outer sprockets (You may need to change these for longer screws)


Please note our controllers are locked and will stay locked to protect the hours and  hours we spent programming and devolving them. Sorry no exceptions.


Photos of rear gears and spacers are not included

Customer review:

Graham C I don’t think the BBSHD is weak as people say. Abuse it yes and something will fail just like any mechanical product. My motor was purchased from Francis Janssen in November 2017. Since then I have completed 7000 miles with approx half of those miles with a Luna Ludicrous controller fitted. My 20 miles daily commute, downhilling, bmx tracks, trails the lot ! I’ve not touched anything internally on the BBSHD and it’s running better than ever, all these stories of nylon gears failing I’m sure is down to the rider, have some mechanical sympathy and you’ll be fine. As Francis states I have now fitted the ASI 800 running on 72v, I followed his advice, got my chain line in order, correct gearing and 500 miles later she is absolutely flying, a weapon indeed. It’s far exceeded my expectations, high revving, smooth ramp up of power, throttle response, acceleration is crazy compared to the Ludicrous, top speed, all fantastic and so much fun, it does not feel like the motor is working hard. I am extremely pleased. I can thoroughly recommend this conversion and Electron Cycles ( Francis Janssen) for there professional services. Go for it !