Shifting into Clutchless

February 3, 2007 by Rob.

One of the questions raised during the ICE out last week was the viability of EV America’s clutchless design.  Specifically, does the design burn out the transmission synchronizers?  Apparently, some transmissions have weak synchros that cannot withstand the extra inertial stress added by having the motor mass permanently attached to the clutch.  Unfortunately, there is no way to know if the RAV’s transmission can handle it until after I try it and ruin the synchronizers.

The alternative would be to keep the clutch in place and attach the motor to the flywheel.  The downsides of this approach are 1) it adds rotation mass to the system and decreases my range and 2) “normal shifting” with the clutch in can over rev (destroy) the motor.
So here is my plan.  I’m going to go ahead and go clutchless.  I am going to keep my flywheel as a backup if I change my mind later.  The worst case would be that I’d have to get the transmission rebuilt ($1500+).  The likely bad case is that I’d need to get a new adapter plate made ($600).

Now I just have to get the measurements from the bell sent off to the machinist!  That’s my job for tomorrow.

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