Bummer. The motors need to be mechanically isolated for this build - one on each rear wheel. During turns, the wheels will be rotating at different speeds. I have two BLDC's and would dearly love to use them for this app. As I see it, and please correct me if i'm wrong, the downside to using a separate controller for each motor, is the conflicting loads created during turns - the inside wheel drawing higher amperage - pushing the system into inefficient territory.Link said:In theory, if you were able to weld the axles together, they could probably be run in a sort of weird series. Can't be run in series without sharing an axle or whatever because their phases would need to be on at different times.
Papa said:As I see it, and please correct me if i'm wrong, the downside to using a separate controller for each motor, is the conflicting loads created during turns - the inside wheel drawing higher amperage - pushing the system into inefficient territory.
Link said:Like I said, you won't be doing 0 radius turns at speed, so the amount of power going to the wheel is going to be small and can be totally burned off without ill effect.
Can't really comment on RLT's 2WD thing, but they shouldn't have to have separate packs.
Well, I just finished connecting two brushed PM motors in series, and they peformed as I suspected;RLT said:At least as far as my BRUSHED 2WD build experiences show, the only way to get full time all wheel drive is to have all motors have their own isolated controllers and battery packs. They can't even share a single throttle. I have no idea as to why this is the case, but my real-world experience has shown it to be the case, at least with the motors, and (BD36) controllers I tried it on.
RLT said:Every time I have tried putting two motors in series, it only took two fingers pinching the motor shaft, to stop one quite easily, even when they were up to speed .... I have tried it on 250 watt currie bike motors and on 3/4 horsepower treadmill motors.
Papa said:Electronic "posi" is a nice feature to have when traction suffers, but I question its efficiency (and elevated tire wear) when the road gets twisty. As such, I'm leaning towards ditching the brushless for this app. Thanks all
If the build had 4 wheels and 50/50 weight distribution, I'd try it. Unforunately, this is a trike with only 33% of the laden weight on its single steer axle. My previous trike build (with diff) exhibits mild understeer at speed, and u-turns on gravel isn't exactly textbook - posi would no doubt exacerbate both conditions. As such, with brushless, I'd feel much better if both motors electronically communicated with each other. Maybe there's a way, maybe not, dunno.johnrobholmes said:The turn radius and tire scrub wouldn't be an issue at all IMO.
diver said:I'm going to run two eteks in my trike in parallel off one controller just for the fun of it. that is my winter project and i cant wait to get started on it.
Mathurin said:going for parallel or series should be doable with brushless also, EG:
Papa said:If the build had 4 wheels and 50/50 weight distribution, I'd try it. Unforunately, this is a trike with only 33% of the laden weight on its single steer axle. My previous trike build (with diff) exhibits mild understeer at speed, and u-turns on gravel isn't exactly textbook - posi would no doubt exacerbate both conditions. As such, with brushless, I'd feel much better if both motors electronically communicated with each other. Maybe there's a way, maybe not, dunno.johnrobholmes said:The turn radius and tire scrub wouldn't be an issue at all IMO.