Thread Tools Search this Thread
Old 01 August 2011, 21:20   #1
TRevor Lawson's Avatar
Country: UK - England
Town: Stotfold
Boat name: kimozo 2
Make: Ribtec
Length: 5m +
Engine: Mercury 115 efi 4 st
Join Date: Jun 2011
Posts: 228
Advice please

Hi , I have a couple of questions to any one who can help, Thanks in advance.

Will a 4 mtr rib with a 25 hp on back be faster than a 4 mtr sib ( hon wave t 40 , blow up keel ,alloy floor), given same load, sea conditions etc, just thinking sib has more suface drag ,and flatter bottom?

Also i guess thr rib will be a better/smother ride for same conditions?

TRevor Lawson is offline   Reply With Quote
Old 02 August 2011, 08:31   #2
RIBnet admin team
Poly's Avatar
Country: UK - Scotland
Boat name: imposter
Make: FunYak
Length: 3m +
Engine: Tohatsu 30HP
MMSI: 235089819
Join Date: Sep 2005
Posts: 11,621
Two different models/brands of rib won't necessarily give the same performance so a definitive answer is difficult.

However the rib is likely to be heavier (possibly significantly so) especially if you start to add seats, console, aframe...
The rib is likely to have more of a V-hull than the honwave - v-hull = harder to move through the water.
Once on the plane some rib tubes completely clear the water reducing drag. I'd guess most 25HP/4m combinations will still have some tubes rubbing in the water most of the time.

All in I doubt you will get faster than a similar sized SIB with the same engine - you may not even be able to match it (but both will do very roughly 20 knots). However the ride will definitely be more pleasant on the RIB.
Poly is offline   Reply With Quote
Old 02 August 2011, 08:56   #3
Country: UK - England
Town: Sussex
Boat name: Bombard
Make: Aerotec 380
Length: 3m +
Engine: Mercury Mariner 15hp
Join Date: Jul 2010
Posts: 3,381
Faster in same conditions is a bit of a red herring though - in the UK anything more than a slight or very gentle moderate sea is a real PITA in a SIB and will limit your top speed far more than the engine. However, a reasonably deep V RIB will think nothing of a moderate or worse sea and will therfore in 'real' conditions almost always be faster. On 'glass' there might be a slight difference but in the real world where moderate is the norm...
Max... is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT. The time now is 12:22.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2023, vBulletin Solutions, Inc.