Having researched the forums & asking the relevant questions,
I bought myself a eVolve system for my Revolution 13.
Took my time reading & measuring everthing twice so as not to make a mistake. on completion it was time to hit the water.
After loading the car & driving to the river, I put the Revo on the Trax Cart,
and set-up everything before walking it into the water.
There were a few ski boats around so I desided to quicky pedal over to the other side of the river (to quiet water) before operating the motor.
Normally, when I pedal at normal pace, I can do 6.5KPH.
So you can imagine my shock when I pedaled across the river and could only do 3.6KPH. (OMG, surely the eVolve can't cause that much drag).
Also I had no right turn from the rudder, straight & left no problem.
Desiding to continue with my testing, it's time to power up.
Slight hum from the motor, expected that, no problems, time to hit full power.
Very disapointed, full power & pedaling, only doing 7.2KPH
I headed back to shore, dismounted and went to grab my trax cart from behind the seat, Oh S--t, It's gone, I've lost my cart, looked out on the water but can't see it floating anywhere. pulled the Revo over to the grassy bank so as not to scrape the hull, pulling it out of the water, the Revo lifts up and "Yes" theres the cart still under the hull
After reading of so many others before, I too have suffered the embarasment.
I also fount that the power cable was catching on the rudder bungy cleat,
stopping the rudder from turning right.
Removed the trax cart, repositioned the power cable, went back out on the water. Very impressed with the eVolve motor, everything I expected, now I don't have to worry about over-excertion with currents, head winds, etc.
Montedane 
