This is the original Coro Speed boat just before the first launch. I had a lot of fun scooting around with my 1.2 hp Gamefisher motor. I’ve had build plans for this for some time now. I used a 6mm thick fluted plastic sheet for the hull.
A little later I added this arced decking taped to the PVC railing.
This is the Coro Speedboat II. A wooden transom was added so I could stretch out the hull 7 inches, allowing me to carry more weight in the boat. Later I added a trolling motor and battery, totaling over 50 extra pounds. The gas motor and gas-can weigh in at 35 pounds. I did a lot of Lake Union runs with this fun boat. Once I learned how to get it up to plane, I was scooting at 9 mph with the 40 year old Tanaka 3 hp 2 cycle gas motor. Unfortunately I had to make some cuts on the inner wall of the fluted plastic 2″ flaps that joined to the wood transom to make a good seal between the two. It always worried me that a blow-out could occur any time at this weak point, so I never made plans for it. If you what to know more about these previous models, I have separate entries on this website.
I woke up one morning wondering if the transom were folded origami style, similar to my first boat, could it hold the 50 pounds of deep cycle battery and trolling motor? I ended up building the shorter speedboat hull above, but used PVC trim for the inner frame work instead of wood board on my longer version. This cut down on the build time from my previous boat. The hull was also widened some for more water displacement.
This proved to work! The boat does ride a little lower in the water than my other boat, but I don’t have to worry any more of a sudden surprise dunk! I have yet to get any water coming over the cockpit in my new boat, even while encountering some rocking waves.
This is a dual powered boat. I can go gas or electric, depending on my mood. This post is for the gas version. Unfortunately I don’t have videos or pictures yet of the boat on the water with the Tanaka motor, but it works fine. I’ve lost about one mile per hour due to the shorter, wider hull, but 8 mph is still fun, and I ride around with confidence knowing there won’t be a blowout on the hull.
BUILD PLANS are now available in the ‘Plans’ tab.