First Real DIY Boat - Tiny Might

For the past few weeks i have been doing quite a bit of research on building my own DIY boat. After looking over a few plans i feel the the 12' Tiny Might boat on Glen-L is a good choice.

I am still in the cost / planning stage if the project and i am slightly stuck when it comes down powering the boat. I'm not looking for a lot of power, just something small to move around with. So far i really like the Honda KA20A3 as an engine. I will have a few design issues as far as cooling and spark arresting is concerned, but i can get past those.

Where I'm stuck is how i should get the power to the prop. I have seen quite a few people mention the borg warner velvet drive, but i am not sure how to mount one of these to the engine. It looks like the engine side uses a spline shaft to connect.

Secondly, are the velvet drives even a good option? I plan on tuning the honda ecu to limit rpms and adjust the vvt as much as i can for a better low end. But are there any other non v-drive systems that offer forward, neutral, and reverse?

 

Why do you think you need better low end? Slow spinning prop doesn't need much torque so you don't really get to use the extra omph at low end if the setup is propped so that the engine can reach highe rpm.
Sounds complicated for a 12 ft boat.

 

Hi Alex,
did you finished your boat? I am also considering Tiny Might build.

Kerosene, maybe you will know, are in EU available some
reverse transmissions for inboard gazoline engines up to 100 hp?
New production? I will use Wartburg engine so will probably
end up with used LEWO but would like to see also other.