Reply
 
Thread Tools Search this Thread
 
Old 18 May 2011, 05:50   #1
Trade member
 
Dry Run's Avatar
 
Country: UK - England
Town: portsmouth
Boat name: Hullabaloo
Make: Humber
Length: 8m +
Engine: 225 Optimax
Join Date: Mar 2011
Posts: 776
RIBase
Any Ideas?

One of my Dryt Stack customers has recently re-engined their Avon 620 (the hull with the fins that poke down) and have changed from a Yamaha 115 to a "counter rotating" Suzuki 150 (don't ask!!!). They now say that they are experiencing a definite "tilt" to the Rib when under power. They have altered the angle of the fin on the cavitation plate, but to no effect. They have tried putting ballast to one side of the boat, but this needs at least 100kg to correct and will play havoc with the fuel consumption. He's considering moving the engine but only has about an inch and a half on the transome to play with. He's also been considering trim tabs. So, before he embarks on any wild and expensive fixes; what do you guys think? I'm sure it's been discussed before, but any new ideas would be welcome.
Attached Thumbnails
Click image for larger version

Name:	DSC02070.jpg
Views:	204
Size:	76.3 KB
ID:	59455   Click image for larger version

Name:	DSC02071.jpg
Views:	197
Size:	50.8 KB
ID:	59456  
Dry Run is offline   Reply With Quote
Old 18 May 2011, 06:01   #2
Member
 
Country: UK - England
Town: Mighty Penryn
Boat name: Little Joe.
Make: Avon Searider
Length: 4m +
Engine: Honda BF50
Join Date: Aug 2005
Posts: 8,869
Offset.
__________________

__________________
Mollers is offline   Reply With Quote
Old 18 May 2011, 06:12   #3
Member
 
Kernow Buoy's Avatar
 
Country: UK - England
Town: Cornwall
Length: no boat
Join Date: Oct 2004
Posts: 1,518
Quote:
Originally Posted by Mollers View Post
Offset.
or in his case Onset!
__________________
Kernow Buoy is offline   Reply With Quote
Old 18 May 2011, 06:46   #4
Member
 
Country: UK - England
Town: Southampton
Make: Ballistic
Length: 7m +
Engine: Yam 225
Join Date: Jun 2010
Posts: 1,003
how about a normal rotating Yamaha 115 ?

__________________
Starovich is offline   Reply With Quote
Old 18 May 2011, 06:50   #5
Member
 
Kernow Buoy's Avatar
 
Country: UK - England
Town: Cornwall
Length: no boat
Join Date: Oct 2004
Posts: 1,518
Seriously, I think he's going to have to move that engine, the one and a half inches may be enough, either that or find a conventional rotating Suzuki gearbox, but you did mention expensive!
__________________
Kernow Buoy is offline   Reply With Quote
Old 18 May 2011, 06:53   #6
Trade member
 
Dry Run's Avatar
 
Country: UK - England
Town: portsmouth
Boat name: Hullabaloo
Make: Humber
Length: 8m +
Engine: 225 Optimax
Join Date: Mar 2011
Posts: 776
RIBase
Quote:
Originally Posted by Starovich View Post
how about a normal rotating Yamaha 115 ?

I think he was quite happy with the Yam 115, but unfortunately despite claims of military quality security someone stole it from his boat while it was at a nearby "rival" dry stack (not mentioning any names)!!! Still, at least they didn't take the whole Rib.
Dry Run is offline   Reply With Quote
Old 18 May 2011, 07:00   #7
Member
 
Nasher's Avatar
 
Country: Other
Town: Principalite d'Chaos
Boat name: The Nashers Revenge!
Make: Ocean & Bombard
Length: 6m +
Engine: Suzi DT200EFI, DT9.9
MMSI: "Mmmmm SI" she said!
Join Date: Jan 2004
Posts: 4,445
I'd agree that moving the engine is probably the way to go.
Probably a inch will do.

Changing the gearbox may be a very expensive way to move the tilt the other way.


Nasher.
__________________
RIBBED For extra pleasure.
Member of the ebay Blue RIB cover club.
Member of the Bombard 380 Aerotec club
Nasher is offline   Reply With Quote
Old 18 May 2011, 07:51   #8
Trade member
 
Dry Run's Avatar
 
Country: UK - England
Town: portsmouth
Boat name: Hullabaloo
Make: Humber
Length: 8m +
Engine: 225 Optimax
Join Date: Mar 2011
Posts: 776
RIBase
Thanks for the comments. I think we'll go with an engine move as it's relatively easy. If it works, I'll let you all know.
Dry Run is offline   Reply With Quote
Old 18 May 2011, 08:05   #9
Member
 
Country: Finland
Town: Helsinki
Boat name: SR 5.4
Make: Avon
Length: 4m +
Engine: Toh1 3,5 Yam 90/2S
Join Date: Oct 2009
Posts: 919
How about different prop, that also might change something, test 4 blade or otherwise differrent?
__________________
fun on a boat is inversely proportional to size...sort of anyway
C-NUMB is offline   Reply With Quote
Old 18 May 2011, 09:27   #10
RIBnet supporter
 
bedajim's Avatar
 
Country: UK - England
Town: Rutland
Length: no boat
Join Date: May 2006
Posts: 2,500
Ask Hightower, he's more up on this sort of thing
__________________
bedajim is offline   Reply With Quote
Old 18 May 2011, 11:41   #11
Member
 
Hightower's Avatar
 
Country: UK - England
Town: Fareham
Length: 6m +
Join Date: Sep 2003
Posts: 7,855
Quote:
Originally Posted by bedajim View Post
Ask Hightower, he's more up on this sort of thing
Funny you should mention that.......Here I am!

I have a CCW 150 mounted on a 6.2m Vipermax. 11/4" - 11/2" from the center line to port side will be about spot on.

If he wants to sell the 150, let me know?
__________________
Andy

Looks Slow but is Fast
Member of the ebay Blue RIB cover club.
Hightower is offline   Reply With Quote
Old 19 May 2011, 03:03   #12
Trade member
 
Dry Run's Avatar
 
Country: UK - England
Town: portsmouth
Boat name: Hullabaloo
Make: Humber
Length: 8m +
Engine: 225 Optimax
Join Date: Mar 2011
Posts: 776
RIBase
Thanks to everyone for their help and Hightower for the specialist advice. Will move it in the next few days and let you know if it works. I have a few different props, so might play around with those just to see if it makes any difference. Cheers again!
Dry Run is offline   Reply With Quote
Old 19 May 2011, 07:22   #13
Member
 
Cookee's Avatar
 
Country: UK - England
Town: Salcombe, Devon, UK
Boat name: BananaShark
Make: BananaShark
Length: 10m +
Engine: 2xYanmar 260 diesels
Join Date: Mar 2003
Posts: 4,225
Ask him if it makes a difference when trimming it out - I think he'll find that with a bit of trim the problem will disappear!
__________________
Cookee
Originally Posted by Zippy
When a boat looks that good who needs tubes!!!
Cookee is offline   Reply With Quote
Old 19 May 2011, 13:10   #14
Trade member
 
Dry Run's Avatar
 
Country: UK - England
Town: portsmouth
Boat name: Hullabaloo
Make: Humber
Length: 8m +
Engine: 225 Optimax
Join Date: Mar 2011
Posts: 776
RIBase
Cheers, might ask him about the "trim out" thing
Dry Run is offline   Reply With Quote
Old 16 July 2011, 04:16   #15
Member
 
kubcat's Avatar
 
Country: Australia
Town: Sydney
Boat name: Lunasea
Make: Ribtec 890SX
Length: 8m +
Engine: Yamaha ME 421STI x 2
Join Date: Aug 2009
Posts: 474
Quote:
Originally Posted by Dry Run View Post
Thanks to everyone for their help and Hightower for the specialist advice. Will move it in the next few days and let you know if it works. I have a few different props, so might play around with those just to see if it makes any difference. Cheers again!
Any feedback yet?
__________________
kubcat is offline   Reply With Quote
Old 16 July 2011, 05:25   #16
Trade member
 
Dry Run's Avatar
 
Country: UK - England
Town: portsmouth
Boat name: Hullabaloo
Make: Humber
Length: 8m +
Engine: 225 Optimax
Join Date: Mar 2011
Posts: 776
RIBase
Thanks to everyone for their help. I'm pleased to report tha we moved the engine and guess what? It worked!!!! Boat is now perfectly balanced! Cheers again.
Dry Run is offline   Reply With Quote
Old 16 July 2011, 10:20   #17
Member
 
Hightower's Avatar
 
Country: UK - England
Town: Fareham
Length: 6m +
Join Date: Sep 2003
Posts: 7,855
Glad we could help.
__________________

__________________
Andy

Looks Slow but is Fast
Member of the ebay Blue RIB cover club.
Hightower is offline   Reply With Quote
Reply

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 -5. The time now is 00:08.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.