Drive train shunt at low speeds

[londiniumperson]

Elephant in the room!
Have other owners experienced drive train shunt at low speeds, the nearer to zero the worse it feels?
I'm always aware of it at 2mph and lower, especially back if I'm moving/stopping at zero on display.

[FDAD]

Elephant in the room!
Have other owners experienced drive train shunt at low speeds, the nearer to zero the worse it feels?
I'm always aware of it at 2mph and lower, especially back if I'm moving/stopping at zero on display.

Care to give more details?

[Left4Cookies]

Sorry I'm not a native speaker, so I'm a little unsure of what you exactly mean by "drive train shunt". Is it a sudden jolt before at low speeds before coming to a full stop?

[londiniumperson]

LMGTFY
Extract from Wikipedia:

Driveline shunt occurs when a vehicle gives an abrupt jolt while coming on or off overrun or freewheel. It is caused when the gearbox or other transmission linkages do not immediately relay changes in engine output to changes in wheel speed. There is a very brief delay before the backlash is taken up in a sudden, abrupt manner.

https://en.m.wikipedia.org/wiki/Driveline_shunt

[keithr]

Have other owners experienced drive train shunt at low speeds, the nearer to zero the worse it feels?

In single pedal mode it's a bit jerky, which I think is down to not very smooth control of the brakes (the Nissan LEAF is much smoother coming to a halt and pulling away from a standstill in e-pedal mode). I believe the Nissan uses a computer controlled electric motor to control the operation of the brake master cylinder, and I guess the Honda has something similar, but whether it's hardware or software related the Honda for some reason is less smooth. It's almost as though it has grabby brakes.

I've driven in single pedal mode virtually all the time so far, so I don't know how it fares when having to brake manually. I may try it on my next drive out of curiosity.

[Trykpaa]

Yes, know the feeling. You can soften it greatly by applying very little throttle when slowing down.

Its only in one-pedal and seems to occour in the transition between driving and stopping. Guessing a cause? Probably due to motor controls at very low rpm is difficult without very high resolution modulation. Maybe motor controls is open loop (sensorless) on which case it would be natural consequence of a design decision. I would have chosen the same solution.

BTW My friends Tesla S does the same

[ChesterUK]

I think it can be a little difficult to manage creeping speeds, barely turning the wheels sometimes, but otherwise it's fine. Compared to the abrupt acceleration just when you don't want it on modern injected motorcycles between no and partial throttle, this is a non-issue.

[advance2020]

When driving I’m normally in OPM by default, except when pulling out of my drive, and manoeuvring in and out of my garage. The only time I have experienced any transmission issues is when I have been rather lax, in my driveway, and switched from Drive to Reverse, without using the brake. So not surprising as the car was suddenly being switched from rolling fwd to reserve. Otherwise, no I don't think there is an issue.

I would add that Driving in OPM with max 3 chevrons, the car seems “locked” to the pedal, and it provides much more responsive braking than just using paddles for regen in normal Drive mode. No lag or shunt at any speed.

[londiniumperson]

When driving I’m normally in OPM by default, except when pulling out of my drive, and manoeuvring in and out of my garage. The only time I have experienced any transmission issues is when I have been rather lax, in my driveway, and switched from Drive to Reverse, without using the brake. So not surprising as the car was suddenly being switched from rolling fwd to reserve. Otherwise, no I don't think there is an issue.

I would add that Driving in OPM with max 3 chevrons, the car seems “locked” to the pedal, and it provides much more responsive braking than just using paddles for regen in normal Drive mode. No lag or shunt at any speed.

Next time you're in the car try creeping forward in stop/start driving at zero or 1 mph (definitely don't go above 2mph) in OPD, it's very easy to do and I'm sure that you'll feel the transmission shunt.

[advance2020]

When driving I’m normally in OPM by default, except when pulling out of my drive, and manoeuvring in and out of my garage. The only time I have experienced any transmission issues is when I have been rather lax, in my driveway, and switched from Drive to Reverse, without using the brake. So not surprising as the car was suddenly being switched from rolling fwd to reserve. Otherwise, no I don't think there is an issue.

I would add that Driving in OPM with max 3 chevrons, the car seems “locked” to the pedal, and it provides much more responsive braking than just using paddles for regen in normal Drive mode. No lag or shunt at any speed.

Next time you're in the car try creeping forward in stop/start driving at zero or 1 mph (definitely don't go above 2mph) in OPD, it's very easy to do and I'm sure that you'll feel the transmission shunt.

the only time experience any 'shunt' which I would describe as take up in transmission slack, is if I'm on a slope.
And it is obvious why this can happen, if the weight of car is being stopped by the motor locking up, rather than the brakes being applied direct to the wheels.
Clearly in this scenario the drivetrain between motor and wheel hubs will experience a significant torque load, depending on the degree of the scope.
So in this situation I would normally use the brake, as you would in normal car with a clutch/gearbox.

As I said above, this doesn't happen on my drive, which is flat.
I think you are looking for problems that don't exist.