Grin: Frankenrunner Series: L10 & MT 2022


The Frankenrunner is the field-oriented controller which was introduced in March 2022 as a stop-gap substitute for the delayed Phaserunner V4 Series. Configuration is with the same Phaserunner Suite of Software and the only real difference with the PRV4 is that it is available today and looks different!

Simply put, it matches all of the specifications and connectors of the upcoming Phaserunner V4 Series today and improves upon the PRV3, so if you need something more powerful than the Baserunner V4 Series right away, then this is for you.

The internals are based around a stock ASI BAC855 with all of the Phaserunner V4’s modifications tacked onto the end rather than embedded in a custom enclosure. Granted, it is not quite as slick and compact as the PRV4 promises to be, however it still delivers the same punch, and boasts all the updated features that will be present in the Phaserunner when it is available… with present indications being some time in/after August 2022.

Has there ever been such a capable eBike Controller in need of as much love as the new Frankenrunner? We reckon it’s a cult classsic.

The Frankenrunner includes all waterproof signal connectors, a 9 pin OEM main cable to support the use of certain 3rd party displays, support for motor temperature sensors, and direct attachment of PAS or Torque sensors.

This controller was designed as a universal device that can fit on almost any bicycle frame and handle almost any motor system in the 500-2000 watt power range. You can power it from a 24V battery or a 72V battery, and run your phase current to peaks of over 90 amps, though the continuous current capability without additional heatsinking is typically 45-50A.

The Frankenrunner_L10 has a cable exit for compatibility with Grin motors featuring the L1019 connector, while the Frankenunner_MT is connectorised for separate cable harnesses between the controller and motor.

Grin have potted the electronics so they are both 100% waterproof and visible.


• Wide Operating voltage range from 20V to 88V (21S Li-Ion, 24s LiFe)
• Remote on/off switch compatible
• Compatible with CA3-WP display and control device
• 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
• Virtual Electronics Freewheeling allows you to experience zero drag with direct drive motors
• Higher motor efficiency than typical trapezoidal controllers
• Torque based throttle command (no twitchy throttle with powerful system)
• Automatic thermal rollback to prevent controller overheating

Frankenrunner L10 Controller
• Compatible with Grin motors with the new L10 Standard Cable
• Uses Over-moulded L1019 Motor Connector and WP8 CA Plug
• 87V Max Battery Voltage and 96A Peak Phase Currents
• Includes XT60 to Anderson Battery Cable.

Frankenrunner MT Controller
• Compatible with BBSHD (requires this BBSHD Harness)
• Uses MT60+JST Motor Connection
• 87V Max Battery Voltage and 96A Peak Phase Currents (~55A at Thermal Rollback)
• Includes XT60 to Anderson Battery Cable.

Frankenrunner Tube Mount
Mounting plate that allows you to attach your Frankenrunner controller firmly to almost any bike tube.



Phaserunner Software Suite from Grin Tech, Mac
Phaserunner Software Suite from Grin Tech, Linux
Phaserunner Software Suite from Grin Tech, Windows
Windows drivers for the FTDI chipset inside the USB-TTL adapter can be found through FTDI here

Connectors are sold separately! Click here to see what is available.



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