Need some advice

[LXIX]

As many of you know I recently bought a Clinton 7.5 hp Motor and a inflatable boat.

I rebuilt the carb and it runs well. However I have a question as to whether I am getting all the speed I can out of this motor.

The boat is about 70lbs, I go a modest 260lbs. On the water according to the GPS on my phone I top out at 4 mph. The motor does plane the boat however in your opinion am I getting all I should out of this motor or could, I get more by lowering the tramsom height (which would involve a saw)?

Any opinions are appreciated.

Thank you,

Brian

 

[WillyBWright]

Re: Need some advice

If you're planing, consider yourself lucky. Disregard the GPS. It's obviously wrong.

 

[steelespike]

Re: Need some advice

If your toping out at 4 mph your not planing.Thats what they call displacement speed.6-8 mph is about the max displacement speed.
On the right boat light with a pretty good width at least 10 ft.long you in the middle seat with a tiller extension handle it might plane barely.
We used to easily plane our 12 ft flat bottom steel boat with about 200 lbs aboard and a 5 hp Gale motor.But I feel the Gale has more power than
your Clinton.I don't think your little boat lends itself well to getting you up on the water.

 

[LXIX]

Re: Need some advice

Ok maybe my definition of planing is incorrect, when I go full throttle the bow rises up about 6-8 inches and from the shore I have been told that the bow actually comes out of the water. When I throttle down the bow goes back down. When the bow is out of the water like that is that considered planing?

Keep in mind my boat is an 9' long, 5' wide inflatable (basically the size of being a sheet of plywood). It's a Sevylor T68. Here's the link to the specs.

http://www.sevylor.com/marine.html

Thanks,

Brian

 

[CATransplant]

Re: Need some advice

Nope. The rising bow by itself doesn't denote planing...

Planing occurs when less of the boat is in contact with the water, allowing the boat to skim across the water rather than plow through it.

Inflatables are different in many ways. But...if you're only going 4 mph, you aren't planing.

 

[MikDee]

Re: Need some advice

Usually when you can see a roostertail in your wake, you're planing.

 

[steelespike]

Re: Need some advice

The rounded edge of the bottom and tubes makes it difficuilt for the boat to shed the water as it tries to get on top and plane.The actual flat planing surface is probably 4 ft. and lots of rounded edges the water clings to.
Still with your weight forward it might plane.A longer boat with more natural weight forward will lay down a little easier when on the edge of planing.