I'd rather you not.  The boat could handle the weight of the motor by itself, and the transom is pretty sturdy.  BUT, the operator needs to kneel in the stern to get the outboard started---and cuss and spit and fight with it when it doesn't.  The fine-ended Chester Yawl is going to be very unhappy with a person crouched back there.  

Personally, I'd love to see an inboard electric motor in the Chester Yawl.  With the weight of the installation amidships it'd be the prettiest electric launch around.  Add a nice awning to complete the effect.

  John, what do you think about the trolling motors that are designed to mount onto an outboard? Could one of those be modified to work? I think Minn-Kota make one....

 Rich,  I am building a Yawl and intend to try a trolling motor for exploring slot canyons from our houseboat on Lake Powell, what thrust motor and what range are you getting, what battery? 

  My intention is to use the largest capacity gel batteries that a pair of stock rowing seats will fit over and then attach them by hanging a floor panel from long through bolts, pulled tight against blocking inside the seats. The seats are already moveable for trim adjustment, rigging a remote throttle can't be too difficult and steering could be by a yoke and push-pull tiller to keep mass out of the ends. With all that weight on the floor (you're sitting on the batteries) a low proportionally sized awning would look and work great. 

Thanks for the responses.  John, I hadn't thought about the problem with starting the motor.  Good point.  For now, I wull stay with my 34 lb. thrust Min Kota that I bought used for $60.

Because I finished the boat so late in our New England fall, I really didn't have much time to experiment with the electric motor.  But I did discover a few things:  plywood pieces (padded) on each side of the transom are a must, the battery(mine is a huge 29 weighing 60 lbs.) needs to be located forward with  #6 cable extensions to the motor, and a telescoping tiller extension is also a must.

But it is quiet and moves the boat well even against the tidal flow in the Housatonic River.

The reason I was looking into an outboard was the differene in weight (the Honda weighs in at 31 lbs while the electric motor(18 lbs.) plus heavy battery are close to 80 lbs. Then there are the wires to deal with.

I also found out that in Connecticut even occasional use of a trolling motor means the boat needs to be registered (with those ugly numbers near the beautiful bow.

Hey, maybe I'll just row all the time and forget the pesky motors that don't belong on this classy boat anyway!

RichMPL

Check out the Scerry Main Photo Gallery, photo 10 of 102, for an interesting way of adding axilary power to a boat with a fine stern. Also, less emergence language.

Hot glueing 'number plates' to your top sides when you motor can be popped off when you just want to row.

Velcro ? ? 

Make that Skerry.