Mud Motor

What about something like this:

http://s556.photobucket.com/albums/ss10/madmudmotors/MaD Mud Motor Pics/

and here is some videos:

http://s556.photobucket.com/albums/ss10/madmudmotors/MaD Mud Motor Movies/

 

I totally agree with mudslinger use a 6.5 hp ...but look at the complex metal work to support the angle drive ....my design " Thai longtail with 6.5hp Lifan Honda " using a chain drive is much simpler to build and you can use a right hand prop ( or use a V belt or toothed belt .....note the speed in the video with the 200cc ....how slow is it going to be with a 34cc....think of the river current ..