First time with a 25hp o/board

[kevinsc]

Ok on the look for a tiny tach will I use the same prop with slight damage? till decide which prop to get. Flat water might hard as scotland can have windy weather a lot.

[Fenlander]

Kevin I've looked back and not noticed any mention of the speeds where these problems are happening, that would be interesting to know to help give an opinion.

[kevinsc]

Hi fenlander
Thinking about it now I dont think I got onto the plane and you could see the boat cutting the water near the front and it did seem any faster than the 5hp I had. The throttle was about 1/2 to 3/4 any more and the back end felt like it was dipping down so didnt push any faster, but I forgot to say that I had also 1 adult and a child the the boat as well near the front of the boat. Have bought a tiny tach to see the revs on the engine.
Cheers kevin

[Fenlander]

That's what I was wondering... if your description was actually of being stuck in "transition". The difference in the wake will tell you. Off the plane you are seemingly towing a hill of water just behind the boat and on the plane it's like a long merging "V" shape.

[Mikefule]

Good description, Fenlander. I was on the river the other day. At fastest non-planing speed, I was making quite big waves that were slopping against the river banks. I then got onto the the plane and the wake was dying out before it even reached the river banks. On the plane it's a longer, narrower, wake. Off the plane, you are pushing one lot of water and pulling another. The least efficient speed possible is just before you get on the plane.

[kevinsc]

It looks like that I am not getting on the plane and stuck in the transition point as the wake looked quite wide looking, I take it that adjusting the trim would sort this.
Cheers kevin

[Mikefule]

The engine needs to be trimmed correctly, but so does the boat. Just before you get onto the plane, the bow rises as the boat is climbing up out of the hole. You need to get your weight forwards to help the boat over the hump. Weight distribution makes a huge difference. The position of the anchor box, the fuel tank, the safety kit, the helmsman and crew can all help. In my previous SIB, on perfectly flat water, no headwind, and with just me on board, I could just about get it up on the plane with a 3 hp 2 stroke, but I had to sit forward and steer with my finger tips.

[Fenlander]

Edit: My post has appeared after yours Mike so I just wanted to say yes all those things are important but more so when running a 10/15hp where everything being right is needed to get a quick transition... but as I'm saying below Kevin has loads of power in hand to make these things less likely to stop him getting onto the plane which makes it puzzling.

-------------------------------

It's odd as that outboard is very powerful for a lightish SIB with flattish bottom... you should be able to open the throttle and power through the transition in a couple of seconds to reach slightly scary speeds. Trim setings are important but really fine tuning and in truth changing one hole is minimal compared to the excess power you have available.

My Aerotec with 20hp will jump on the plane one hole either side of ideal and regardless of 1-4 people. Yours should do the same.

[kevinsc]

I was hoping for the bigger engine to be a bit quicker and more exciting. Hopefully with a bit of adjustment it will be fine.
Cheers kevin

[kevinsc]

one other thing i dought it has happened unless you have been unlucky just check to make sure your prop hasn't damaged the rubber bush when you hit something[/QUOTE]


Hi jeff
Not sure what rubber bush you mean and the piece missing of the prop I have as it fell off when I touched it
Cheers kevin

[jeffstevens763@g]

Originally Posted by kevinsc

one other thing i dought it has happened unless you have been unlucky just check to make sure your prop hasn't damaged the rubber bush when you hit something

Hi jeff
Not sure what rubber bush you mean and the piece missing of the prop I have as it fell off when I touched it
Cheers kevin[/QUOTE]

center of the prop you will see it if it has or turn it in gear by hand.

as the guys have said you dont seem to be getting over the bow wave caused at low speed [displacement speed] that might be you didn't push it enough at 1/2 revs because the bow lifted right up but my money is the prop pitch needs to come down as fenlander has said trim change either side of the norm won't stop you getting on the plane it just fine tunes it and can change with added weight.
IMO i would go 2nd hole with a 10 1/4 x 11 inch pitch but find out your revs with current prop then you will get all the advice for re-propping if needed.
its a pity you live so far away i have an 11 & 12 inch pitch props you could have tried

[kevinsc]

I have order a tiny tach so will be able to get the revs and see what prop to get.
Cheers kevin

[kevinsc]

Hi all
Just getting the layout sort in my sib but was wondering what kind of depth finder use are using, I mainly go to loch lomond so dont need anything fancy saw this one on ebay
http://m.ebay.co.uk/itm/40m-Depth-Fi...%257Ciid%253A3
Or is it better to get on like this
http://m.ebay.co.uk/itm/Garmin-Strik...%257Ciid%253A1
And also thinking about this battery and a sealed box
http://m.ebay.co.uk/itm/PowerSonic-P...257Ciid%253A16
The battery is for powering a depth finder and led light and charging radio/ mobile, will put up pics when sorted layout.
Cheers kevin

[Yabadabadoo]

Be interested in others thoughts on the 12v 12ah battery as I've just bought one for on board power supply, it's much heavier than I expected. Others have gone for the 7ah..

There's some info on the forum about hours of use for various navigation devices, I don't remember the formula but they'll be a spec of power use on any given device, that requirement and the batteries power will determine how long your battery will go between charges - that figure will be based on full power/brightest screen etc

You'll need to think about a dedicated gel battery charger, there is a forum for batteries! Not all chargers are created equal it would seem

[Max...]

How about solar? You have to be careful with all this stuff though or you end up going down the much trodden route of trying to turn a SIB into a RIB. The beauty of a SIB is the lightweight simple set up, KISS!

[jeffstevens763@g]

i have a 12 AH gel battery[lucus £20 ebay] inside the dash just at the back of the power switch charged from the engine with a socket for charging a phone.
of course as max says mine is probably an over the top example and could be made much simpler by just mounting everything on a seat/ in a peli case etc.

only my opinion and it's down to budget this would be my choice or similar

http://www.force4.co.uk/lowrance-hoo...l#.WTjy7mjyvIU

[Max...]

Looks pretty awesome though. Have you done a build thread on that?

[jeffstevens763@g]

Originally Posted by Max...

Looks pretty awesome though. Have you done a build thread on that?

not as such max the boat has changed from first buying it have a look at my new boat thread.
i got a lot of good comments at ERR about the setup and also from the derby fire brigade when it was in for service at central marine services so i have decided now that it works well as a prototype it needs to be tidied up so i am going to make a mould so it has a nice smooth finish but this time it will have a separate base plate which can be cut to fit other boats and the dash will extend to the bow and look like a conventional bow dodger.
the base plate will be HDPE sheet as it's cheap enough and needs no maintenance.
the top hatches will be katak rubber pull off lids simpler
i'll do a build thread on that [winter project]

[kevinsc]

Yes jeff your setup is very impressive and has inspired me to change things, but I still need to pack it away. So I need to have thing modular, was going to mount things on to a waterproof toolbox I have and put the battery in that then have leases going to the o/b to charge it, also I have a handheld radio so a plug to charge it just in case.
Keep up the good work.
Cheers kevin

[Fenlander]

If you have charging output from the OB a 7ah battery should be fine. We use one for a small Garmin plotter and without OB charging it will go several days out.

Personal thing I'd go Garmin of your linked finders. Not keen on trusting one branded "Lucky" with a Wi-Fi transduced powered by a button battery! Also look at Humminbird units which are about £115.