Reply
 
Thread Tools Search this Thread
 
Old 07 January 2011, 17:03   #51
Member
 
martini's Avatar
 
Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
Join Date: Jun 2005
Posts: 3,021
Quote:
Originally Posted by Erin View Post
I think he's referring to his old 6.5, not his current 7.0. Mine was bought under the guise of 6.5.
Ah ok. Bring back feet and inches I say. Actual feet and inches.
__________________

__________________
martini is offline   Reply With Quote
Old 07 January 2011, 17:16   #52
Member
 
Country: UK - England
Town: Mighty Penryn
Boat name: Little Joe.
Make: Avon Searider
Length: 4m +
Engine: Honda BF50
Join Date: Aug 2005
Posts: 8,841
Quote:
Originally Posted by martini View Post
Is your VM really '99? I assumed it was only a couple or 3 years old, credit to you if it is
The old one ya' numpty.

The current is an '08.
__________________

__________________
Mollers is offline   Reply With Quote
Old 07 January 2011, 17:25   #53
Member
 
Country: UK - England
Town: Mighty Penryn
Boat name: Little Joe.
Make: Avon Searider
Length: 4m +
Engine: Honda BF50
Join Date: Aug 2005
Posts: 8,841
Quote:
Originally Posted by Downhilldai View Post
Mollers' old boat was done back in '99ish (by Olmec, I think )
Henshaw I fawt, but dunno for sure.
__________________
Mollers is offline   Reply With Quote
Old 07 January 2011, 17:34   #54
Member
 
martini's Avatar
 
Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
Join Date: Jun 2005
Posts: 3,021
Quote:
Originally Posted by Mollers View Post
The old one ya' numpty.

The current is an '08.
Osprey's are like chinese, they all look the same to me
__________________
martini is offline   Reply With Quote
Old 07 January 2011, 17:40   #55
RIBnet supporter
 
gotchiguy's Avatar
 
Country: UK - England
Town: Dinard, Brittany
Boat name: Into the Red
Make: Osprey Vipermax
Length: 7m +
Engine: Evinrude E-tec 250HO
MMSI: 235 076 114
Join Date: Apr 2009
Posts: 1,948
RIBase
Quote:
Originally Posted by martini View Post
I thought the HO was just stroked by a fraction of an inch giving a bit more torque
Well to be technical... to turn the 150 into the 150HO is just a map. The 200 to 200HO is a completely different engine, the 200 is 60deg small block and the 200ho is big block 90deg. The 200ho produces 217hp but it is not a racing engine, rather a version of the 200 designed for heavier boats. The 225ho is just a map and a different gearcase, currently the L2 which has low water pickups for those who run them ridiculously high on bass boats, and the 250ho is a 300hp with the racing L2 gearcase and a slight detune. The certification for outboards means they can be +/- 20% of rated hp, and the 250ho is generally regarded as having over 270hp at the prop shaft. Bear in mind however that all HOs are designed for the Yank bass boats and the gearcases are not designed for offshore boats like ours. This is the same for all the Mercury XSs and ProXS, but the Evinrude gearcases are regarded as their weakest point in the racing scene compared to the mercs, some have even bolted on an OMC V8 gearcase to compensate.
Quote:
Originally Posted by Downhilldai View Post
Mollers' old 6.5 Vipermax measured 6.5m and my 5.8 Vipermax measures 5.8m
Really!? You're saying that from the tip of the D fender at the bow to the rearmost point of the Opti is 5.8m?
Quote:
Originally Posted by Erin View Post
Well I've just nipped outside and put the tape measure to mine. Tip to tail it is just shy of 6.8m. I will remeasure tomorrow in the daylight to confirm, but it's certainly over 6.7m
Well... what did I say. I'll check out ours at half term in four weeks, and I'll dig out the measurements of Jigsaw which I recall were significantly over 6.5 like Keiths.

Ok, back to the OP....

Best I've seen on ours is 52 knts with our Viper 22". However Into the Red is not set up for top speed; we have no jack plate and the engine is set quite low for good grip on the water and accelerating, not top speed. Also the prop is designed for cruising economy, not for top speed, a 23" Raker would probably add a knot or two.

Back to my point... I have seen 52knts with full kit but very little fuel - 60litres or less- and only me on board. The conditions were ideal: little chop to aerate the hull but sheltered and calm. Above 50 knts the boat began to chine walk like mental, VMs made in the larger mould (6.5-7.8m) have a very deep chine, and this digs deep into the water and so there is lots of travel to one side before the hull rights itself on the tube and bounces to the other side. Thsi si very scary and maybe what your're referring to. Up to about 47knts however she is fantastically stable, and even with a lot of trim up - 70%+- she stays steady, and normal, comfortable progress can be made at 42knts. For us, the most economical speed is 30knts. Our engine is mounted 1cm above the keel I believe, and this will probably be the cause of your problem. It should be lower, sort this before thinking about props, especially with a CR 'box it will prove expensive!

Also, all UK VMs have an offset of 1.5 inches.. hang on that is about 3cm! Ignore me
Quote:
Originally Posted by martini View Post
Osprey's are like chinese, they all look the same to me
Gotchimum is in strong disagreement with that
__________________
gotchiguy is offline   Reply With Quote
Old 07 January 2011, 17:46   #56
Member
 
Country: UK - England
Town: Mighty Penryn
Boat name: Little Joe.
Make: Avon Searider
Length: 4m +
Engine: Honda BF50
Join Date: Aug 2005
Posts: 8,841
Quote:
Originally Posted by martini View Post
Osprey's are like chinese, they all look the same to me
You reckon'?
Attached Thumbnails
Click image for larger version

Name:	Chinese.jpg
Views:	91
Size:	86.1 KB
ID:	56390  
__________________
Mollers is offline   Reply With Quote
Old 07 January 2011, 17:47   #57
Member
 
Country: UK - England
Town: Mighty Penryn
Boat name: Little Joe.
Make: Avon Searider
Length: 4m +
Engine: Honda BF50
Join Date: Aug 2005
Posts: 8,841
[QUOTE=gotchiguy;383607] Well to be technical.............



Man!! You need to get a girlfriend.
__________________
Mollers is offline   Reply With Quote
Old 07 January 2011, 17:48   #58
RIBnet supporter
 
gotchiguy's Avatar
 
Country: UK - England
Town: Dinard, Brittany
Boat name: Into the Red
Make: Osprey Vipermax
Length: 7m +
Engine: Evinrude E-tec 250HO
MMSI: 235 076 114
Join Date: Apr 2009
Posts: 1,948
RIBase
Quote:
Originally Posted by Mollers View Post
Well to be technical.............



Man!! You need to get a girlfriend.
__________________
gotchiguy is offline   Reply With Quote
Old 07 January 2011, 17:53   #59
Member
 
Country: France
Town: Southampton
Boat name: Alea Jacta Est
Make: Osprey
Length: 7m +
Engine: mercury 300xs
Join Date: Jan 2011
Posts: 27
Quote:
Originally Posted by gotchiguy View Post
Well to be technical... to turn the 150 into the 150HO is just a map. The 200 to 200HO is a completely different engine, the 200 is 60deg small block and the 200ho is big block 90deg. The 200ho produces 217hp but it is not a racing engine, rather a version of the 200 designed for heavier boats. The 225ho is just a map and a different gearcase, currently the L2 which has low water pickups for those who run them ridiculously high on bass boats, and the 250ho is a 300hp with the racing L2 gearcase and a slight detune. The certification for outboards means they can be +/- 20% of rated hp, and the 250ho is generally regarded as having over 270hp at the prop shaft. Bear in mind however that all HOs are designed for the Yank bass boats and the gearcases are not designed for offshore boats like ours. This is the same for all the Mercury XSs and ProXS, but the Evinrude gearcases are regarded as their weakest point in the racing scene compared to the mercs, some have even bolted on an OMC V8 gearcase to compensate.

Really!? You're saying that from the tip of the D fender at the bow to the rearmost point of the Opti is 5.8m?

Well... what did I say. I'll check out ours at half term in four weeks, and I'll dig out the measurements of Jigsaw which I recall were significantly over 6.5 like Keiths.

Ok, back to the OP....

Best I've seen on ours is 52 knts with our Viper 22". However Into the Red is not set up for top speed; we have no jack plate and the engine is set quite low for good grip on the water and accelerating, not top speed. Also the prop is designed for cruising economy, not for top speed, a 23" Raker would probably add a knot or two.

Back to my point... I have seen 52knts with full kit but very little fuel - 60litres or less- and only me on board. The conditions were ideal: little chop to aerate the hull but sheltered and calm. Above 50 knts the boat began to chine walk like mental, VMs made in the larger mould (6.5-7.8m) have a very deep chine, and this digs deep into the water and so there is lots of travel to one side before the hull rights itself on the tube and bounces to the other side. Thsi si very scary and maybe what your're referring to. Up to about 47knts however she is fantastically stable, and even with a lot of trim up - 70%+- she stays steady, and normal, comfortable progress can be made at 42knts. For us, the most economical speed is 30knts. Our engine is mounted 1cm above the keel I believe, and this will probably be the cause of your problem. It should be lower, sort this before thinking about props, especially with a CR 'box it will prove expensive!

Also, all UK VMs have an offset of 1.5 inches.. hang on that is about 3cm! Ignore me

Gotchimum is in strong disagreement with that

The main problem is that if I lower the engine to much, the steering system will it the transom and I may damage the hydraulic cables....

I thinkk I can lower it by 2cm but much more.
__________________
Vipermax is offline   Reply With Quote
Old 07 January 2011, 17:54   #60
Member
 
martini's Avatar
 
Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
Join Date: Jun 2005
Posts: 3,021
Quote:
Originally Posted by Mollers View Post
You reckon'?

Quote:
Originally Posted by Mollers View Post
!! You need to get a girlfriend.
Careful, I can hear the bilges calling you
__________________

__________________
martini 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





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 15:10.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.