Gen2/Implement Reverse Mode
From Unofficial Zero Manual
- A reverse mode is handy when trying to push the bike rearwards uphill, or in tricky traction conditions.
- Sevcon's market primarily consists of forklifts and tractors, so the Sevcon is already set up for reverse operation.
- Naturally, a reverse mode is unsafe for motorcycles beyond a very limited speed (5mph, say).
Trikester worked with Harlan to install a reverse mode switch on a 2013 FX.
- Recent Zero models (2016? seems IPM-related) have a glitch when reverse mode is configured using the standard Sevcon recommendation.
- Zero custom firmware could be interfering, or it could be a custom setting; unclear which yet.
- How It Works
- The Sevcon controller can be programmed to take a digital/binary input as a reverse mode directive.
- The Sevcon as used by Zero has some unused pins; one of the digital inputs will be needed for the extra signal. Use SevCon's DVT software and IXXAT cabling to configure this.
- Since Zero programs the Sevcon to operate in torque mode instead of speed mode, the reverse mode allows the throttle to operate like a variable regen that transitions to reverse from 0mph.
- The transition to reverse can be configured a bit for some motorcycle-specific safety, but mainly to avoid a jerky transition.
- Torque and speed limits can be set separately for reverse operation (40% and 5mph are good to start with).
- The enable needs to be dual-throw to turn off the forward input signal and turn on the reverse input signal, so use a DPDT or SPDT switch, or a SPST switch that drives a relay.
- A momentary push button switch is better for control safety, since any instability while moving in reverse should be resolvable by letting go of the control.
- Any kind of binary switch can be used (toggle, etc), technically, but getting into a stuck reverse situation could be dangerous.
- Mounting the switch should account for keeping the wiring protected and secure, and the switch should either be weather-rated or in a protective enclosure.
- Mount location should be accessible from the left handlebar but not where it can be accidentally engaged.
- Trikester's mount placed it in front of the handle, requiring the index finger to extend to reach it.