Single or twin engine

taff · 11 May 2013, 22:13

At present I have a Humber Assault RIB with a single Suzuki DF70 which is good for 30kts and and a bit more on a calm day.
Am looking at a Humber Destroyer which has twin Mariner 60hp engines, in the advert it says max speed about 26kts, seems a bit low to me or would this be correct?

Cheers, Taff.

willk · 11 May 2013, 22:29

You'll have to indicate size and layout of the two RIBs...

taff · 11 May 2013, 23:18

Mine is 5m long with two person jockey seat, other is 6.5m long with two twin jockey seats.

9D280 · 12 May 2013, 01:01

Before this explodes into a big irrelevant discussion, hae a search for my previous posts on this subject.....

Overall weight will be a factor, but at this end of the scale gearbox size & overall weight will be significant. Also are the quoted figures for your new boat fully loaded with dive kit??? Just a guess, but there are a lot of factors to consider here...

willk · 12 May 2013, 09:25

Quote:

Originally Posted by taff

Mine is 5m long with two person jockey seat, other is 6.5m long with two twin jockey seats.

See, that's apples and oranges - completely different rigs. A friend has a 6.5m with twin Mariner 60s. He struggles to make 28kts at WOT.

Mollers · 12 May 2013, 12:06

Quote:

Originally Posted by willk

See, that's apples and oranges - completely different rigs. A friend has a 6.5m with twin Mariner 60s. He struggles to make 28kts at WOT.

Bet it's a larf going cruising with him.

willk · 12 May 2013, 12:26

Quote:

Originally Posted by Mollers

Bet it's a larf going cruising with him.

It's fine if I use the SIB

yorfuoj · 21 May 2013, 13:14

Go to catamaran ...!

I own a 6.3 south african one, made by Stingray, not a light unit due to a lot of GRP + big 2-men console with 2 front seats, + 2 men-bolster for driver and ... + bow sundeck, but with a pair of 60/70 Tohatsu (2 stroke with 3 carbs) she reaches 44 knots with the right SS props.

Goes to 30 with 12 on board, not bad !