A2B Metro Conversion...more like A2Beast

A2B Monster -

A2B Metro Conversion...more like A2Beast

A2B Metro 2 Monster

When you think of A2B the last thing you think of is speed and performance. This is a custom build for a customer, who came into our shop and he had his mind set on a A2B platform. His goals for this custom build was fairy simple.


-Long Range

-About 35mph Top Speed

-Ability to climb the steep hills on Catalina Island

Needless to say I believe we may over delivered. How does this sound.


-74V Lithium Ion 20AH *Est 50mi range @20-25mph

-50mph Top Speed

-Monsterous torque, along with the small 16" Moped Tires, immense torque is available to climb steep grades.

We started with a well used White A2B metro frame, man this thing needed work, the original ultra motor 350-500W motor was blown. So we quickly tossed that. We had a MXUS 3000W 3T High Speed Wind motor lying around courtesy of my friend at Kinaye Motorsports. We quickly had that laced up to a 20" Alex DX32 which is a nice wide rim. 12G spokes for heavy duty use, but oh no we never intended to put bicycle tires on this bike.

Heidenau K42 Dual Sport Moped tires was used on this build. We also do Moped Wheel lace on hub motors

heidenau k42

 Absolutely gorgeous tires, and gives the appearance of a very aggressive bike. Mounted on the A2B it literally transform the look of the bike into a very muscular Moped look. I have received positive feedback on this build from virtually everyone.

 Next was tackling the controller, originally a MXUS 12Fet Sinewave Controller was used, but that controller quickly blew. Apparently due to the low inductance of the High speed wind on the MXUS 3000W motor. The customer was growing impatient with his bike, so I quickly swapped in one of my Greentime 24Fet 84V 80A controllers. Now this controller is a beast I've had it for almost two years now and it was previously used with the Cromotor to hit 50mph as well. I already knew this motor and controller combo would be beastly but I was eagar to try it.

 First I tried the phase and hall combo color to color, but no luck the motor would stutter. Another positive feature of the Greentime controller aside from its low cost is that it can run sensorless which makes it a snap to find the right phase and hall combo. Since the motor runs forward colored matched and sensorless, I just swapped the yellow and green hall sensor wires and hazza! The motor spins forward smoothly and effortlessly, now we are in business! 

 I spent the last two days running wire, soldering, crimping, mounting tires, and etc. But, the pay off was worth it, I plugged in my 84V lipo batteries and was ready to take the bike on its maiden voyage! Wow, what a rush, this motor has power! 6600W of power to be exactly, this bike really pulls now. 

 In stock form the A2B Metro does about 20mph, but now the A2B Monster does more than twice that speed. I was hitting 48mph before letting off the throttle, it was still pulling! The motor makes such a amazing sound too, sounds like a jet engine on acceleration. Regen was also very strong, especially on smaller wheel diameters the regen effect is amplified but then so is torque and acceleration. I would do most of my braking with regen only, hardly ever necessitating use of the front disc brakes at all. With the regen, even excellent hydraulic disc brakes like the Shimano Zee's are not necessary. 

 Also the way I used in the regen was that the A2B is already equipped with e-brake cutoff switches, I merely just matched the 2-pin connectors from the e-brake to the controller.


 A2B has a hallow frame so it is possible to run wires through the frame for a clean build. You do have to use fish tape and remove the JST connectors before trying to pull them through the frame, as it is narrow. The frame is just too narrow to run a large battery pack inside. We decided to go with a custom aluminum battery box in the rear. 



Update: 1/22/2015 

MXUS 3000 is had a severe internal short is now being replaced another 3000W motor currently used in testing. 42mm stator. Much thicker phase wires and dual hall sets. Performance is very similar to mxus if not more torque.




Update 2/6/2016

Sabvoton Sinewave controller was added to replace the Greentime Controller which was having issues. Since the MXUS motor shorted out, it may have damaged the controller. The Sabvoton Sinewave controller is a fantastic controller, now the throttle is silky smooth, bike runs virtually silent, and regen is more controllable. This controller is capable of 150A battery amps and 350A phase amps. Very easy to program, including regen strength and flux weakening which increases top speed. The battery box is now a 2 piece design, as the customer wants to be able to remove the battery on and off for external charging.


 Videos and more pics to come as the bike reaches completion. This is one of our fastest bikes in the shop and represents our commitment and dedication to high performance electric bikes.


  • Arthur

    Tbis is the best upgrade I have ever see. These frames are great but the iles were ways artificially governed and thus never a great commuter solution for the masses, just the diehards. I have lne amd rode it to work every day that it was warm enough but was always pushed off the side because I couldnt keep up with traffic. This looks like the perfect mix of bicycle portability wkth scooter/local motorcycle power.

  • Jay

    Great engineering man!! wish i could get something like this.

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