AB dinghy with Tohatsu 6 hp OB

[BobH260]

We have an AB dinghy. It is a UL9, 9 ft. aluminum RIB, only about 70 lbs. AB recommend a 6 hp motor for this dinghy and a max motor of 8 hp. It will sort of plane with one person in it. With two people or any kind of load the motor just bogs. It has the standard prop of it. They do sell a lower pitch prop for this motor. I don't know if that will fix the problem.

I'm interested if anyone else is using this dinghy, the size and make of motor used prop and how it performs.

thanks, Bob

[colemj]

If the motor is bogging, dropping prop pitch an inch or two could help tremendously. Maybe look around for anyone with the lower pitch prop that you could borrow for a few minutes?

Mark

[a64pilot]

If it's bogging with the standard prop, I'd look into the health of the motor, most small motors are propped so that they will rev pretty well even if attached to a rather large vessel, or even in a test tank.

[mayday12]

we have the exact dinghy with a 6hp 4-stroke (well 5hp that I put the 6hp carb on ) - planes with 1 person very easily; with 2 people it is right on the edge of planning, but not quite - so very close, feels like just a 1/4hp would pop it up, but no joy. i'm willing to live with it though because the weight difference to the 8hp just isn't worth it. 90% of the time it's just me anyways, and if it's the wife and I we're resigned to the slow lane

[BobH260]

thanks for the tips. I took the prop in and the re-pitched it from an 8" to a 6". They sell this motor with the 6" pitch for use on sailboats. It works much better, no bogging. It will now just plane with me (200 lbs) and our 22lb dog in the bow. Overall it was a big improvement. I may go for a 10 hp engine at the end of the day. The dog likes to go ashore twice a day, with a 5 ft draft in the Bahamas we can be anchored out quite a distance.
I just bought a used Forespar motor lift, if it works out it may convince me to get the bigger motor.
Bob