Achilles LSI310-E w/ Tohatsu 6HP, advice to plane!

[chipko]

12 knots one up plus kit in a 3.1m sib is about on the button to be honest, and definitely planing. Don’t think we’ve ever bettered 14 knots even in a 3.6 tunnel hull sib with 6hp. Two up unlikely you’ll get on the plane.

Tacho wise it’s just reading twice the revs and equating to 1200rpm at tickover and 5000 to 5500 at wot. So your in the right ball park re prop pitch.

Try setting tach at 1P1R as this works for some one pot four strokes despite instructions. In fact just scroll through settings whilst at tickover until around 1000/1200rpm is indicated.

[Fenlander]

To reinforce Chipko's comments...

I think you are actually exactly where we'd expect for speed one and two up. To be able to always plane in all conditions two up you really need to make the jump to a 10hp and even that size in some conditions can be laggy to plane.

I assume this is a single cylinder 4-stroke? I would have started with the 1P1R setting so that should give better readings. Were the max revs readings you reported with one or two folks? The only thought I have left to just achieve a two-up plane would be considering a slightly smaller prop pitch but then one up you may be at risk of over-revving... or bouncing off the rev limiter if it has one.

[Xpedience]

Originally Posted by Steve509926

What model 6hp Tohatsu do you have? The tacho readings you've given and the fact that you say you can't get on the plane, is it possible that you have a 2 cylinder 6hp Tohatsu that, as far as I can find out, is only available as a long shaft?

Apologies for the late response. It's a single spark plug so 1cyl.

[Steve509926]

Originally Posted by Xpedience

Apologies for the late response. It's a single spark plug so 1cyl.

Then it's everything that chipko said and reinforced by Fenlander. You are probably where you should be and to try and gain anymore might be an impossible task without extra hp.

[Xpedience]

Originally Posted by Steve509926

What model 6hp Tohatsu do you have? The tacho readings you've given and the fact that you say you can't get on the plane, is it possible that you have a 2 cylinder 6hp Tohatsu that, as far as I can find out, is only available as a long shaft?

Single spark plug on the outboard tells me it's a 1cyl. Haven't had a chance to measure that shaft but I'm pretty sure it fits the standard of short shaft.