Running times

benc · 21 March 2005, 23:52

Hi all,

I have just gone halfs on a tornado 7.5m rib, twin 115hp engines.

I just wondered if anyone here had a rough idea what type of fuel consumption I am expecting out of this?

Thanks

Ben

jwalker · 22 March 2005, 00:22

Welcome benc. At a guess, about 3 mpg, but it depends how you drive it.

benc · 22 March 2005, 14:39

Thanks for the welcome

When you say, "depends how I drive it"... how would I be driving it to only get 3mpg out of it?

pettal · 22 March 2005, 15:08

Carefully!

I'd estimate that at cruising at 3/4 throttle with the occaisional blip at full throttle and plenty of just chugging around harbours and the like you'll hit your 3mpg.

You'd be suprised how much time you actually spend at 4-6knts getting to and from berths and just poodling around harbours etc.

benc · 22 March 2005, 15:10

We are getting it moored in warsash - about 2 mins from the solent - so not much 6 knots work for us

Doubt we will hit full throttle, t'is quite a beast

How far is it to the isle of wight, does anyone know? - that will probably be the trip I do most

Searider · 22 March 2005, 15:28

Quote:

Originally Posted by benc

How far is it to the isle of wight, does anyone know? - that will probably be the trip I do most

It's about 4 or 5 miles to Cowes. Big sandbank in the way though - best get a chart and some training.

Are the engines 2 stroke or 4 stroke or direct injection - that will make a big difference to the fuel consumption.

Have fun - if you're out over Easter and spot a yellow Scorpion give me a wave. I'm based in Hamble and should be out and about - can show you the way to Cowes.

Regards

benc · 22 March 2005, 16:12

Interesting, might take you up on that

4 Stroke Yamaha 115's

jwalker · 22 March 2005, 16:36

Quote:

Originally Posted by benc

Doubt we will hit full throttle, t'is quite a beast

I bet ya do.

At, or close to, full throttle you'll get simiar fuel consumption no matter what version of outboard you have. X amount of petrol will give Y amount of energy. The efficiency of the burning in IC engines is kinda similar.

Swifty · 22 March 2005, 20:00

Quote:

Originally Posted by jwalker

I bet ya do.

At, or close to, full throttle you'll get simiar fuel consumption no matter what version of outboard you have. X amount of petrol will give Y amount of energy. The efficiency of the burning in IC engines is kinda similar.

Rubbish

my 2 stroke 90 burns about a third more than my mates 4str 80 for the same run. We have done several trips and it allways works out about that. The 2 boats are identicle and top speed is about the same as well. We were around portsmouth and surrounding over the weekend and I used about 70 litres where his used about 50.

I will eat my old hat if i'm wrong.

Tim'mers.

codprawn · 22 March 2005, 23:18

Quote:

Originally Posted by Swifty

Rubbish

my 2 stroke 90 burns about a third more than my mates 4str 80 for the same run. We have done several trips and it allways works out about that. The 2 boats are identicle and top speed is about the same as well. We were around portsmouth and surrounding over the weekend and I used about 70 litres where his used about 50.

I will eat my old hat if i'm wrong.

Tim'mers.

The guy said "at or near full throttle" - I bet on your runs you are not at full throttle all the time which could be causing the difference?

benc · 23 March 2005, 12:42

2x115 hp on a 7.5 rib will make it go like sh*t off a shovel, right?

I wouldn't cruise at full throttle, or even at 75% I wouldnt have thought.

Swifty · 23 March 2005, 16:22

Nah mine goes from bad to worse at WOT. Chris' engine, which I did the comparison with, is much better at all speeds including WOT.

Tim'mers.

jwalker · 23 March 2005, 17:04

Quote:

Originally Posted by benc

2x115 hp on a 7.5 rib will make it go like sh*t off a shovel, right?

I wouldn't cruise at full throttle, or even at 75% I wouldnt have thought.

It depends on the weight and wind resistance of your rib. About 50mph.

You can cruise at whatever you like, it's your boat.