Very Unscientific Fuel Useage Comparison.

[Mollers]

The SR4 has been clocked at 29.5knts when running alongside DHD pulling around 5600rpm. The Missus and I blatted about with it a fair bit on Sat, at WOT or close to. For the day, she used 20ltrs.

I'm not sure, but I suspect, that if we'd covered the same distance at similar speeds 25-28knts with the Vmax (250Etec), we'd not have burnt a great deal more fuel. I need to check the ltr/h figures on the big one at tootalling speed.

[Hambleite]

Well, for comparison, the Scorpion 6.5 with a 150 optimax, at 27knots, 2 up, full tank (165litres) will burn around 23 litres per hour, according to the smartcraft gauges.

They seem to be quite accurate when compared with 'actual' amount of fuel put in and 'amount burned', according to the smartcraft gauges.

32 knots is around 30 litres per hour

42 knots is 59 litres per hour

[Mollers]

Originally Posted by Hambleite

Well, for comparison, the Scorpion 6.5 with a 150 optimax, at 27knots, 2 up, full tank (165litres) will burn around 23 litres per hour, according to the smartcraft gauges.

They seem to be quite accurate when compared with 'actual' amount of fuel put in and 'amount burned', according to the smartcraft gauges.

32 knots is around 30 litres per hour

42 knots is 59 litres per hour

@25knts?

[Searider]

Only getting 29.5 knots with 50hp?

Are they small horses?

Get 26 knots with 30hp on our searider. Big stinky Yamaha horses though.

[Nos4r2]

2 up though. You lose a lot of oomph once you carry a passenger in a 4m. I used to go from 39 knots solo to 33 with 2 people aboard.

Besides, Mollers needs a shave so he isn't exactly aerodynamic

[Mollers]

Originally Posted by Nos4r2

Besides, Mollers needs a shave so he isn't exactly aerodynamic

She's propped to be a w/board tug and there are only 50 gee gees to play with.

[Nos4r2]

Originally Posted by Mollers

She's propped to be a w/board tug and there are only 50 gee gees to play with.

What's your WOT revs? 5600 sounds low.

You might want a bigger pitch for when I finally get myself in gear to organise the 2010 Searider bash

[Mollers]

Originally Posted by Nos4r2

What's your WOT revs? 5600 sounds low.

You might want a bigger pitch for when I finally get myself in gear to organise the 2010 Searider bash

5500-6000. She'll pull 57/5800ish.
I reckon 31/32 knts would be the most you could squeeze out of it.

[Hambleite]

@25 knots?

Well, the engine seems to have a 'natural' sweet spot at a certain rpm. The engine kinda goes all smooth and runs quite a bit quieter. It just happens to give 27 knots at this rpm.

25 knots requires less rpm but the engine seems a bit 'growly' at that rpm.

The hull seems to like going a bit faster too.

Next time I'm out I'll check the stats at 25 knots.

[Nos4r2]

Originally Posted by Mollers

5500-6000. She'll pull 57/5800ish.
I reckon 31/32 knts would be the most you could squeeze out of it.

That surprises me. Biggles' old sr4 with a Yam 50 4 stroke went almost as well as mine. I seem to remember he was hitting 36 knots without problems.