Mine as we'll is a direct drive. You can get an electric clutch which is like the ones used on riding lawn mowers to engage the blades. They are a little over $125.00 . I wanted to keep mine as simple as possible to eliminate multiple failure points. I put a catch latch on mine so when I tilt it all the est ip it will lick in that position.

Why did y'all go with the sd over a long tail?

We didnt want it hanging back that far and also a surface drive is easier to drive and you get better speeds from what I've been told. I

how big is the boat you plan to use?
One option for small boats is this: http://www.ebay.com/itm/COMPLETE-LONGTAI...5f8&vxp=mtr
My 14' fiberglass boat with hunting gear and me goes about 6 m/hr with 6.5HP longtail

It will go on a 14 ft modified v but as soon as I get it finished ill get a 12 or 14 ft flat bottom.

Im going to get the 16 hp duromax from maxtool

I agree with Brock2013 about having a SD instead of a long tail. Although there are several advantages to a long tail I like the SD ease of turning and maneuverability along with the increase in speed.

Ive got no complaints about my Duramax and would recomend it to anyone. A little back ground on these engines is the Duramax, Preditor and Lifan engines are Honda Clone engines and there are ton's of after market items for these engines. You can google GoKart performance engines and get huge list of vendors and parts. I removed the govener to increase the RPM and build an exuast to improve air flow which cost nothing. The other Items I will get is a after market fuel pump ($25.00) If you have any question about the engine or how to work on it just let me know.

Thanks! can you post some pictures of how you made your exaust? did you just cut the old one off and use the same manafold?

and how long of a drive shaft is it? the thing that im having most dificulty with is how the shaft will be suported where the sprocket is i think ill put a pillow bearing on the wall closest to the engine then just have my bearings and seals suport it coming out of the shaft housing.

I built one before last season. Used 20hp Honda. Then upgraded internals with go cart racing parts. Aluminum belt housing. Hardened shaft with 11x8 mud buddy prop. Boat is 16'. GPS 17 mph with two people, dog, and dekes. I need to change to a larger prop b/c I have a lot of water blow out with current prop. Should run mid twentys after