Electric trike - pedal sensor bi-directional?

[Kerosene-Tin]

Hello All
Ive purchased a used E-trike thats in the mail, a few questions come to mind im wondering if anyone can help


ive got lower limb cerebral palsy so things are a bit stiff. in my youth I used to pedal fine though.. needless to say its going to be a journey of pedal straps and short cranks for a while

These hall sensors on pedal assist 250w bikes,its going to be a while till i can go full circle pedalling,instead getting to the limits and pedaling back for another power stroke

are the hall sensors bi directional so id have power both on the forward power stroke and reverse thatd translate into forward power uninterupted?

as far as i can tell, a hall sensor just wants the magnets to brush on by to give throttle to the electric motor, it doesnt care about direction?

additionally these blokes want 600 for a spare battery.. although it looks same as the ones on kogan (trikebike)

anyone had any luck in using 3 12v lithium batteries wired up?

Thanks

[Gordonhooker]

Hi,
I have an electric bike and it does not seem to provide forward assistance if I pedal backwards, on mine it is pedal forward assistance only. Does the bike have a throttle that may help as you get it all worked out, but bear in mind it is illegal to go over 6kmh (I think) using the throttle. I don't know the answer to battery question other than 600 sounds about right for a battery depending on the size.

Update:
These are the laws for QLD it may change in another state:

Queensland E-bike law
Queensland also allows two types of legal ebikes on the road:

270w e-bikes
Pedelec bikes that are EN15194-certifed

As of June 2019, the Queensland Government issued new changes on the road requirements of power-assisted bikes, addressing concerns about the illegal electric moped-like bikes being hired and sold as power-assisted bikes.

The new law states that high-powered mopeds and motorcycle-like bikes don’t belong on the footpaths. Additionally, all bicycles, including the power-assisted classes, have to use pedals as the primary source of power. This makes it clear that the motor attached from these bikes should only operate when a rider pedals, with an exception of helping it run in the initial take-off (my words - thumb throttle)with no more than 6km/h limit. In general, the motors from these ebikes should only assist the rider to pedal and must not exceed the 25km/h speed limit.

[bychosis]

I think typically these have three poles of sensor which would indicated that it may be able to sense 1-2-3 vs 3-2-1. The motors also have three corresponding poles so the don’t fire in reverse.

[skyblot]

The crank rotation sensors are designed to work only in one direction, though in a couple of DIY kits I've seen them work in both directions - a mismatch between the sensor and the software.
Also, the software needs a certain amount of rotation before switching on the motor, typically 1/2 to a full rotation. These settings are generally not able to be changed though I'm sure there are clever people out there who could access the code and re-write it.

The e-bike battery includes a battery management system (BMS) that controls the cell balance, low voltage cut off, over voltage protection, and probably other things. Wiring up 3 other batteries negates these protections that bike and battery makers have found to be a very desirable thing.

Could your lower limb movements be helped by using very short cranks? Like 120mm or 140mm long? Perhaps the much reduced knee bend and foot travel might help?

[Kerosene-Tin]

Thanks so much to everyone here for the detailed replies, apologies for the late response.. ive been infected by covid on friday night coughing up a lung and a half feeling like absolute hell

The trike should arrive today so ill upload some good infomation that maybe of benefit to others

in reguards to the shorter cranks, 155mm is the smallest i can find on trisled.
im assuming 140-120 are them bolt on crank adjusters?

id have to say these hall sensors having 3 pole rotational sensors surprises me but likewise impresses me at the complexity

very much looking forward to a detailed reply when ive got more focus

Have a good sunday

[skyblot]

in reguards to the shorter cranks, 155mm is the smallest i can find on trisled.
im assuming 140-120 are them bolt on crank adjusters?

Cranks shorter than 152mm are very rare as production items. Very short cranks are generally done by someone drilling and tapping the cranks in the desired location, then trimming the excess off. Not all cranks are suitable, usually the more expensive they are, the less suitable - hollow cranks, exotic materials etc. Fortunately there are suitable economical cranksets about as a starting point.

Also, on an upright bike/trike, shorter cranks means raising the saddle to maintain the same leg reach...