Reply
 
Thread Tools Search this Thread
 
Old 15 May 2007, 20:39   #1
Member
 
Country: UK - England
Town: Bristol
Make: Humber Destroyer
Length: 5m +
Engine: Yamaha 70
MMSI: 235057234
Join Date: Mar 2005
Posts: 385
twin installation

Hi there, i am thinking about buying a rib with twin 60's on the back, do the props need to be counter rotating to keep the boat balanced, any help and info would be appreciated, cheers.
__________________
Tims Osprey is offline   Reply With Quote
Old 15 May 2007, 20:48   #2
Member
 
Country: UK - England
Town: West Sussex
Length: no boat
Join Date: Oct 2002
Posts: 3,872
Quote:
Originally Posted by Tims Osprey View Post
Hi there, i am thinking about buying a rib with twin 60's on the back, do the props need to be counter rotating to keep the boat balanced, any help and info would be appreciated, cheers.
counter rotation is only available from 135HP upwards
__________________
Andre
Andre is offline   Reply With Quote
Old 15 May 2007, 21:01   #3
Member
 
Country: UK - England
Town: Bristol
Make: Humber Destroyer
Length: 5m +
Engine: Yamaha 70
MMSI: 235057234
Join Date: Mar 2005
Posts: 385
top man Andre, i thought that was the case, with the bigger engines that is, how much power would twin 60's put out? cheers, Tim.
__________________
Tims Osprey is offline   Reply With Quote
Old 16 May 2007, 07:22   #4
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,951
Tim, they should be the equivalent to a single 90 hp outboard. Do consider the higher fuel costs and servicing of twins.

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 16 May 2007, 09:32   #5
Member
 
Country: UK - England
Town: Bristol
Make: Humber Destroyer
Length: 5m +
Engine: Yamaha 70
MMSI: 235057234
Join Date: Mar 2005
Posts: 385
Hi pete, thanks for that, another question is will the boat be comfortable planing with only one engine running and the other tilted up? or will there be a bad balance issue? cheers, Tim.
__________________
Tims Osprey is offline   Reply With Quote
Old 16 May 2007, 09:58   #6
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,951
You would need to change one of the props to reduce the pitch to get the boat to plane properly. The steering linkage between the two engines may also be a problem with one tilted and one down. At sea if one broke down the offset of the good one wouldn't worry me, I would be more interested in getting home.

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 16 May 2007, 19:52   #7
Member
 
Country: UK - England
Town: Bristol
Make: Humber Destroyer
Length: 5m +
Engine: Yamaha 70
MMSI: 235057234
Join Date: Mar 2005
Posts: 385
Fair comment pete, i would feel the same too.
__________________
Tims Osprey is offline   Reply With Quote
Reply


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 07:50.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.