# Aid to easier shifting on clutch-less setup



## DavidDymaxion (Dec 1, 2008)

Clever use of what you have!


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## Stunt Driver (May 14, 2009)

I'd like to pull flywheel/clutch out, since i'm not using it anywa, and the question comes - how do I put some sort on brake on empty shaft end and connect it to clutch pedal, do help slow down motor while shifting. 

Alternatively I'm looking for electric way to slow down series motor a bit without reversing contactors. That would be a much cleaner solution. 

Forum, Any ideas?


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## DavidDymaxion (Dec 1, 2008)

I haven't tried this myself, but I've read if you put a resistor across the motor (or just short it with a wire), it'll quickly stop spinning.


Stunt Driver said:


> I'd like to pull flywheel/clutch out, since i'm not using it anywa, and the question comes - how do I put some sort on brake on empty shaft end and connect it to clutch pedal, do help slow down motor while shifting.
> 
> Alternatively I'm looking for electric way to slow down series motor a bit without reversing contactors. That would be a much cleaner solution.
> 
> Forum, Any ideas?


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## Stunt Driver (May 14, 2009)

it is easy to test, but I would doubt that. It may be true for perm magnet motors.

I wonder if it will work to connect smaller ~6v batteries in reverse to field and arm, with out disconnectig controller? clearly have to be two separate, because field is directly connected to armature, and you can't reverse motor from single power source.


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## Dave Koller (Nov 15, 2008)

Have you read this thread as it is on that subject - ongoing :

We are looking for ways to slow down the motor during shifting but in clutch designs -- same motor - same reasons! 

http://www.diyelectriccar.com/forums/showthread.php/warning-evs-owners-use-clutch-39000.html


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## Dave Koller (Nov 15, 2008)

Stunt Driver said:


> it is easy to test, but I would doubt that. It may be true for perm magnet motors.
> 
> I wonder if it will work to connect smaller ~6v batteries in reverse to field and arm, without disconnecting controller? clearly have to be two separate, because field is directly connected to armature, and you can't reverse motor from single power source.


Look at the schematics for most Curtis controllers ( have to find that one and it is for an older model - it was reverse engineered lol) but the M2 and the internal PLUG diodes could be done external of the controller and used in some way to break - I have not looked into that... but my go-cart disk brake on the output shaft and solenoid operated PWM brake pads might work... ONLY under no torque conditions so little different under no clutch!


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## Stunt Driver (May 14, 2009)

Thanks for link, i'll check in. Just didn't expect anything usefull in chitchat section, so don't look there. 
I definitely have way to slowdown motor, but i don't like mechanical ways like that applied to something that can be driven by electricity, and controlled by small button on shift stick, or even on same clutch pedal (i have safety switch there anyway)


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## Dave Koller (Nov 15, 2008)

Stunt Driver said:


> Thanks for link, i'll check in. Just didn't expect anything usefull in chitchat section, so don't look there.
> I definitely have way to slowdown motor, but i don't like mechanical ways like that applied to something that can be driven by electricity, and controlled by small button on shift stick, or even on same clutch pedal (i have safety switch there anyway)


lets work on the electronic way by all means! WITHOUT blowing a controller!  No regen just slow it down...


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## Thaniel (May 25, 2008)

I think the idea is a good one. Rev matching the motor. the nissan 370z has rev matching on it's ICE that makes up and down shifting smoother (still uses a clutch) If the controller of an EV could be programed to rev match the motor when downshifting and brake/slow the motor when upshifting it could be a sweet set up.


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## mlohara (Nov 29, 2014)

Thaniel said:


> I think the idea is a good one. Rev matching the motor. the nissan 370z has rev matching on it's ICE that makes up and down shifting smoother (still uses a clutch) If the controller of an EV could be programed to rev match the motor when downshifting and brake/slow the motor when upshifting it could be a sweet set up.


I've been looking for info on implementing this setup mentioned here. I found one other posting, where someone was implementing this: http://www.diyelectriccar.com/forums/showthread.php/electronic-synchromesh-shifting-37764.html 

Any updates? I plan to convert a 1999 Porsche 911 using AC-76 or similar, and it would be amazing to have a rev-matching system that would use regen to slow the motor when up-shifting, and speed up the motor when down-shifting, for smooth, fast clutch-less shifting.


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## Tesseract (Sep 27, 2008)

mlohara said:


> ...it would be amazing to have a rev-matching system that would use regen to slow the motor when up-shifting, and speed up the motor when down-shifting, for smooth, fast clutch-less shifting.


You are basically saying you want the motor controller to autonomously control throttle to aid in shifting without a clutch; that's a huge safety risk for a very minor increase in convenience.


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## Woodsmith (Jun 5, 2008)

I still ponder having a sprag clutch (one way clutch) instead of the flywheel/clutch/coupler.

It would allow the motor to drive the trans, but would freewheel if the trans tries to drive the motor. That would save the motor from over speeding if you accidentally found too low a gear.

Also for gear changing when changing up there would be no difference to a solid coupler without the flywheel, but when changing down the trans will spin up the sprag clutch only and not the mass of motor so making down changes easier.

Sounds fine in theory but, one day, I'd love to see if theory translates into practice.


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