New SIB owner with some questions.

[DonMn]

Hi all,

I recently picked up a 1999 AquaStar JS310 with a early 80's Mercury 8hp as partial trade on my old 1969 Boston Whaler 13', my main boat is a 1974 16' Boston Whaler with '96 90hp Evinrude. My intial plan was to keep both of my Whalers and have them for seperate uses, but I didn't want to have two boats on trailers sitting in my driveway. I don't know a lot about SIBs but I see them all the time on the rivers I run on, Zodiacs are the norm up here. But a SIB appealed to me because of not needing a trailer for it; I've been mainly inflating/deflating at launch and transporting it rolled-up and in the back of my truck.

On the weekends I go camping on the Mississippi River and bring the dogs along, the SIB is towed behind my Whaler as a gear boat then used for exploring the back waters with a 1952 Johnson 3hp. I'm mainly using the 8hp as a kicker motor on my Whaler, but I'm starting to think this little boat would make a great river runner with the 8hp on the back of it. The guy I traded with claimed it could do 20 mph...

So here are my questions...Is 20 mph realistic with my set-up? If not what top speed should I expect? Will a 8 hp be big enough to plane the SIB out? Would one of those whale tails on the motor be a good idea? The SIB seems to be built nicely, is AquaStar considered a quality SIB?

Thanks,

Don

 

[Sea Rider]

Re: New SIB owner with some questions.

Welcome to the forums,

To plane or not to plane, that's the question. If that's a (3.10 meter sib) will have my doubts if obtaining 20 mph with a 8 HP, that's a reasonable speed with a 15 HP. Will also depend if it's a air deck, alum deck, how well you have tubes, keel inflated to, boater's weight, perfect transom engine height match, correct trim and water conditions.

No need to install tails on engine, simply trim engine correctly, move your weight forward and full throttle to have bow down and plane faster. Go for a wot GPS ride and check max speed. Due to Globalization, you have now a days different brands with fancy names related to water, definitely one more of the Asian sibs market available, use and time will tell if good quality.

Happy Boating

 

[DonMn]

Re: New SIB owner with some questions.

Thanks for the input Sea Rider, I figured 20mph was a little too good to be true. I'm bringing my SIB to a local lake tomorrow and get my top speed with one of my handheld GPSs.

Don

 

[DonMn]

Re: New SIB owner with some questions.

Okay, I'm pretty suprised at the speed I got today out of this little inflatable today...It wasn't a bad day to get my top speed, but wasn't horrible day either. I was on a small lake a few miles from my house, winds were 7 mph south by southwest and the lake had a pretty good chop to it. I had two different GPSs with me today a Garmin Nuvi 550(combo on/off road) and a Lowrance Expidition H20, the Lorance gave me an extra .4 mph over the Nuvi. I had the myslf(I weigh 215), about 5.5 gallons of fuel, the foot pump, oars, seat, life jacket, both GPSs, and one beer. The one beer was a mistake, I needed one more because I dediced to putt around the lake for a little bit. I installed a new impeller and prop seal last weekend and wanted to test out the motor too.

With the wind 17.1 mph, against the wind 15.5 mph. The wind died down and I got 16mph even, I had the motor dropped in the #1 trim position and it's a wood floored SIB. When I had the prop off I forgot to look at what pitch prop I have, so I might be able to pitch up a little and get a few more mph. I'm thinking about losing the seat run the SIB with about a half gallon of gas in the tank and have my friend that weighs about 140 lbs do a speed test, I can actually see someone doing 20mph in this little inflatable.

I found out my SIB maintains a nice plane at 10-11 mph, I drop below 8mph I lose the plane. To me it's a 11 mph or a 3 mph boat, it's nice to know it's got enough speed to get me across a lake at a decent rate or know I have enough power to go upriver when the mighty Mississippi River is high.

It's a fun little boat.

Don