The Baserunner is a compact field oriented motor controller (FOC) designed to fit inside the baseplate cavity of popular Hailong and Reention downtube battery packs. It has the same functionality and amazing feature set of our popular Phaserunner motor controller, but in a smaller / flatter profile. This makes it ideal for ebike systems that can benefit from the discreteness of a controller hidden inside the battery mount.

 Baserunner Installed in Downtube Battery

Unlike the Phaserunner which works with up to 72V nominal batteries, the Baserunner has a maximum upper voltage 60V which restricts it to 52V nominal batteries or lower, and it has correspondingly lower current limits due to the smaller size. We have two models in production. The progoma; baserunner_Z9 model uses standard mosfets with the common 9-pin motor plug and has a maximum peak phase current of 55A, making it perfect for small 250-500 watt nominal hub motors. The slightly longer L10 model uses performance mosfets and can support up to 80A peak phase currents, making it an ideal option for medium to high power motors.

  Baserunner_Z9 Baserunner_L10 Phaserunner
Max Voltage 60 V 60 V 90 V
Max Phase Amps 55 A 80 A 96 A
Continuous Phase Amps 30-35A 45-50A (est) 50-55A
Motor Connector Type Z910 L1019 MT60 or L1019


  • Slim Profile fits in popular battery cradles
  • Direct plug for both V2 and V3 Cycle Analyst, or new CA3-WP model
  • Passthrough of internal motor speedometer signal to CA display
  • Proportional Regen available through throttle signal or stand alone wire
  • Works both Sensored and Sensorless, and even with very high eRPMs
  • Waterproof, 100% potted electronics
  • Fully Programmable parameters (regen voltage, max phase and battery currents etc.)
  • Field Weakening allows you to run motors faster than normal back-emf limit
  • Embedded LED for easy troubleshooting diagnostics 
  • Virtual Electronic Freewheeling for removing drag of regen capable hub motors
  • Wide Operating Voltage range from 20V to 60V (14S Li-Ion, 24s LiFe)
  • Automatic Thermal Rollback to prevent controller overheating


The Baserunner is produced with a few different connector and cable options.


The controller itself has a short pair of + and – power leads which would be terminated to match the plugs on the battery pack. There are flat 4 pin, flat 5 pin, and round bullet terminals that we have seen on these batteries. At Grin we now use the flat 5-pin terminal for the smaller Hailong 01 cases, and the round bullet terminals for the larger Hailong 03 packs. Reention downtube batteries usually use a flat 4-pin terminal. If the baserunner is purchased with a battery pack we will install the mating terminals, while if it is purchased by itself then the user would be expected to solder the wire to the terminal already present in their existing battery cradle. 


The motor cable is 38 cm long and is terminated with either the Z910 HiGo style 9 pin waterproof plug or the L1019 10 pin plug. These connectors include the 3 phase wires, 5 hall wires, and one or two additional signal wires for temperature and speed readings to the CA3. The cable length is sufficient to reach from the downtube battery mount to the rear hub motor on most bicycle frames, but for front hub motors or extra long frames we have both 60cm and 90cm extension cables available too.


The throttle connection uses the 3-pin JST-SM plug standard allowing you to have a simple throttle controlled system. Under the heathshrink of the throttle plug is a pair of white and yellow wires that can be hooked up to a remote on/off switch. It's possible to separate the blue and green signal wires of the throttle connector if a separate ebrake input is also desired. There is also a forwards/reverse wire that can be optionally wired by you so it may be shorted to ground to enable reverse functionality.

Cycle Analyst

The Baserunner is supplied with the waterproof 8 pin HiGo plug (WP8) for the new CA3-WP. Baserunners ordered with our Ready-to-Roll kits all use the WP8 connector. The extra wires allow for a handlebar mounted on/off control and a direct pass-thru of the motor temperature signal for hub motors that include a thermistor. In the Baserunner controllers, the speed signal for the Cycle Analyst comes directly from the speed wire in the L10 or Z9 motor plug. If the application requires connection to an older CADP plug, a WP8->JST adapter should be purchased here. If the Baserunner is intended to be used without a CA or display, the ON/OFF wires from the throttle plug MUST be connected to have the controller turn on.


The back of the Baserunner includes a TRS jack for connecting the Baserunner controller to a computer or USB-OTG capable smartphone using USB->TTL serial cable. This is the same cable used with the Cycle Analyst and Satiator charger, so if you already have it then great. But if not, then we'd recommend purchasing the communication cable with the Phaserunner. When not in use, the there is a small rubber plug included to seal this hole.


If you purchase the Baserunner from Grin Tech along with one of our downtube battery packs, then it will come pre-installed inside the battery cradle. No installation is required. If you are purchasing the baserunner to add to an existing battery, then the stock aluminum heatsink that came with the battery cradle needs to be removed and replaced with the baserunner assembly. You remove the connector pins from the original plate and move those over to the baserunner, soldering the + and - wires appropriately.

Difference between Hailong and Reention Baseplates

On the larger Hailong-03 cases, you will also need to drill a hole in the back of the plastic base in order to access the TRRS programming port.

You can also use the Baserunner controller without a downtube battery pack if the form factor is appealing for your application. In this case, it can be removed from the aluminum controller case and bolted directly to the heat spreader.


The Baserunner controller uses the same Phaserunner software suite available for WIndows, MacOS, Linux, and Android devices

Phaserunner Suite, Windows, Portable

Phaserunner Suite, Windows, Installer

Phaserunner Suite, macOS (Requires macOS 10.12 or newer)

Phaserunner Suite, Linux

There is also a version for Android that is in development, and available for beta testers on the Google Play Store. This requires the use of a USB OTG compatible device, as well as a USB OTG adapter to connect our USB->TTL programming cable to the micro USB or USB-C connector present on most smartphones.  

The drivers for the FTDI chipset inside the USB-TTL adapter can be found through FTDI here -


User Manuals

At present we have not completed separate user manual for the baserunner motor controller. Most of the setup and tuning process is the same as our Phasernuner device, and we recommend using the Phaserunner manual as a reference.

Download Latest V2 Phaserunner User Manual with XT60-MT60 Plugs



CAD Drawings

Where to Purchase

The Baserunner controllers can be purchased from Grin directly by themselves, or as part of a full ready-to-roll kit system.