ASI BAC4000 for Sur Ron with Bypas battery: Loom, Display, Mounts, Fully Assembled and Programmed

£1,249.00 (price including VAT)

ASI BAC4000 for Sur Ron with Bypass battery: Loom, Display, Mounts, Fully Assembled and Programmed

Out of stock



ASI BAC4000 for Sur Ron with: Loom, Display, Mounts, Fully Assembled and Programmed

BMS Byspass service Included (see notes)

Our latest and improved fully motor protected upgrade!!!

Sur Ron “Enduro” ASI BAC4000 (60v) Controller + Display + Mounting Brackets + Fully Assembed and Programmed.


Higher Volts, Higher Amps Higher RPM+  Higher Speed !

This is truly plug n play
All taxes and import duties paid and free UK shipping

Power sets from 7500W (can later be turned up if an after market battery is purchased)


Sorry no EU or  International shipping


Our controllers as per our agreement with ASI are locked wth no customer access granted.


We lstened to our customers and improved and change things as this product evolved. We originally started this project 18 months ago. Thats 18 months of learning and evolving just on this one device. We truly belive this is the very best Sur Ron controler upgrade on the market. we KNOW that other sellers have copied our program (they say, to be copied is the greatest compliment), but now  we have pushed the boat even furthur. Our latest program has been revised to include MORE power! Improved thermal roll back for motor protection, no problems with up hill starts or roll backwards stalls, no cutting out, extra water proofing, higher grade materials used. Stainless steel metal work and extra added powerder coating (you scatch it, it stil wont rust!!).

The acceleration is greatly improved over standard. Remember when your bying this kit, It was only us and one other busines (ERT) that created this product for the Sur Ron. Others have copied, but NO ONE can compete against the qulity of these kits.


This controller can take battery swaps ranging from the standard untouched Sur Ron battery. But we hve set this kit to work with std and Bypassd Sur Ron battery.  This is predominatly a 60v Bypassd battry and not “tuned” for a std battery.

The controller now features  a full working display showing: speed, power, battery charge, date and trip. Set with 5 power levels as default that can be flicked at the touch of a button on the fly  (just your thumb, no gloves off or stopping), Can be used like a gearbox to slip up and down the power levels (5 levels set as our default) to suite your terrain and riding style.

The controller comes fully potted and with all leads and looms fitted and waterproofed. The mounts are in place, 3D printed with the possible aditon of protective “Wings”.

Power levels:

5 power Levels slowly increseing from very low to full power.

Unleash more performance and range with correct gearing.  Higher gears (Smaller rear sprocket) does not mean higher top speed. Over labouring the motor with the wrong gearing costs top speed, acceleration and range.

A fast efficient spinning electric motor goes better – simple!.

Controller Feature Set

  • FOC (Field Oriented Control)
  • improved torque throughout the rev range
  • Higher RPM compared to the stock controller.
  • 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
  • Loom
  • Mounting Kit
  • Install Instructions
  • Display


Others copy, se we improve and change. The old APT display (as used by everyone else) had a tendancy to steam up on a hot day if  the  bike had been washed with a hose or exposed very heavy rain, So guess what? we went to another display manufacturer and had another display devolped just for us. We are the only Sur Ron kit that now uses our dedicacted display. Its got our programing and logo on it, so lets see ow long before we are copied again (PS, its really good to use)!

There is no actual need to to reset the display between voltages. However the battery status will show incorrectly if you do not. This is a simple few button press in the settings.

The important factor to remember are:

On a Sur Ron “Bypassed” Battery. The battery if full at 67V and dead at 48v, However you will not be able to charge your battery if you go below 54V. This does not harm the battery but you will need to buy or “Recovery Charger”  if you want to get around 30% more range than a std SR battery:

On a Sur Ron standard Battery. The battery if full at 67V and empty at 54v, The BMS in battery will stop your battery from drainingg too far. In reality there is very little gain on running a STD SR battery  with this controller.

Sur Ron Battery Bypass Service

Fast Turn Around, More Range and More Power for an aftermarket controller.

Sur Ron Battery Bypass 

Buy this listing, Will send you shipping details. Send your battery to us and we will return it to you, fully and safely bypassed within days of receiving it.

Having your battery bypassed will allow it to produce higher power It will also free up anpther 6V or range equivalent to about 46% more: HVC 67V – LVC 54V,  to a new  HVC 67v – lvc48v

The Sur Ron standard battery has battery monitoring system known as a BMS with crazy over cautious settings (we belive to allow for all the differnt temperatures in world from counties as cold as winter Alaska to summer in Dubai). The industry standard for a battery of this configuration, is 67V fully charged and 48V low voltage cut off. The  cells are designed to give much more power than the 4600 watts, the original controller is set to – its being starved!

The cells in the Sur Ron battery are design to supply 10Amps per cell continuously and with its 11P configuration is designed to give 110Amps or 6600W continuous or bursts much higher.

Not only will you now be able to have significant power increase (if you buy an aftermarket controller), you will also gain an addition 46% of battery (if used in conjuction with a “Recovery Charger” to go below 54V) by allowing the battery to use its full volt range. A standard Sur Ron battery has an over safe crazy low voltage cut off (LVC) of 54V. The cells used are designed to go much lower. Changing the battery to an industry recognised level of 3V per cell, The battery can go lower to 48V (16s = 16 * 3V), and increase of 6v or 46% (with aRecovery Charger)!!!

To go lower than the standard 54v and allow re-charging, you will need to purchase a Recovery Charger, This includes your return postage, labour, materials, and recovery charger and still 20% for the VAT man.


Using too high a power mode on this battery may shorten or damage the battery. Please ask you controler supplier for their advice.


 Recovery Charger – to go below 54V (standard charger works form full to 54V)

To recover a Standard 60v Sur Ron battery/Bypassed battery that has been drained too far for the OEM Sur Ron charger to work (voltage below 54V).


Please note that ElectronCycles no longer have any association with ERT

We reserve the right to slightly modify or change this product without notice.


Buyer releases Electron Cycles or any person trading on or behalf of the business known as Electron Cycles from any liabilities, therein known as Electron Cycles (expressed or implied, arising by law or otherwise) that may occur from the use of products sold by Electron Cycles and purchased by Buyer. These products are being sold for “Off Road/Competition Use” only and may be used only on two wheel vehicles (bicycles, electric bicycles, two wheel electric powered vehicles) used solely for “Off Road/Competition” (off-road being defined as a private land with land owners permission and not public highway or byway). The Buyer also recognises that Lithium batteries are classed as hazardous and should not be: stored, used, charged in place, facility any area that is not fire proof or safe to do so. That batteries should not be taken into the family home, office, workplace or school place. No other applications are intended or implied. The Buyer of product sold or provided by Electron Cycles acknowledges and agrees that Seller disclaims any warranty and expressly disclaims any liability for personal injury or damages or any damages to vehicle, expensed occurred, personal property or third persons. Electron Cycles will uphold the warranty of the manufacture of the product sold for a period of six months from date of purchase from manufacturer defect. In the event a manufacturer’s warranty exists, it is agreed and stated that Under no circumstances shall the seller or manufacture be liable for any labour charged or travel time incurred in diagnosis for defects, removal, or reinstallation of this product, or any contingent expenses.

Additional information

Weight 2.9 kg
Dimensions 35 × 20 × 20 cm