Go Back   RIBnet Forums > RIB talk > Engines & props
Click Here to Login

Reply
 
Thread Tools Search this Thread
 
Old 08 February 2007, 19:10   #1
Member
 
Country: UK - England
Town: Bristol
Make: Ribcraft
Length: 5m +
Engine: Yamaha
Join Date: May 2006
Posts: 4,299
Tohatsu Auxilary for searider 5.4

i know this is short notice but, any ideas on the right aux for this hull,?? ive found a superb price for a 3.5 Tohatsu 2 stroke,(13kgs) is this big enough to do the job?? and also will it fit on the back in an emergency,??
or do i need a 5 hp,??
im planning a long run, from the severn Bridge in the summer all the way around the coast ending up in Teignmouth on the south coast,i do need some sort of back up,, Any ideas?? Thanks chaps
__________________
matt h is offline   Reply With Quote
Old 08 February 2007, 20:08   #2
Member
 
Country: UK - England
Town: Essex/Vendee
Boat name: shockwave,Voluntry 2
Make: Pac 22/ searider5.4
Length: 6m +
Engine: 180hp turbo,yam 90
Join Date: Nov 2004
Posts: 1,022
Hi Matt,I,m sure you know really, rule of thumb 1hp per metre it wont change however good the price is for a 3.5hp is.Sorry
__________________
PeterR is offline   Reply With Quote
Old 08 February 2007, 22:56   #3
Member
 
Country: UK - Wales
Town: West Wales
Make: Vipermax 5.8, SR4.7
Length: 5m +
Engine: 150 Opti, F50EFi
Join Date: Sep 2005
Posts: 6,299
Matt - I wouldn't dismiss this until you've heard from someone who's actually tried one of these on a SR5.4.
__________________
Downhilldai is offline   Reply With Quote
Old 08 February 2007, 23:01   #4
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,054
RIBase
Rule of thumb doesn't really work on the smaller Seariders unfortunately as the transoms are too narrow and the positioning of the transom eyes can get in the way too. It's literally a case of use what you can and hope it's enough unless you mount a specific bracket for one.

Take your boat with you and try them on it. It's the ONLY way you'll find out if it'll fit.
I struggle to get a 2hp single screw-clamp type Evinrude on the back of my 4m-there's maybe 2mm between it and the main engine at full lock.
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 08 February 2007, 23:24   #5
Member
 
Country: Other
Town: Oakley
Boat name: Zerstörer
Make: Ribcraft
Length: 5m +
Engine: Suzuki DF 140
MMSI: 235050131
Join Date: Jun 2003
Posts: 3,931
Quote:
Originally Posted by Nos4r2 View Post
I struggle to get a 2hp single screw-clamp type Evinrude on the back of my 4m.
Is that the hybrid outboard. Petrol and electric shock powered
__________________
https://www.xfire.com/download/
Biggles is offline   Reply With Quote
Old 08 February 2007, 23:40   #6
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,054
RIBase
Quote:
Originally Posted by Biggles View Post
Is that the hybrid outboard. Petrol and electric shock powered
Yeah

Did you like my strange dance moves?
I've sorted that out now-it had a hairline crack in the plug cap.
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 08 February 2007, 23:52   #7
Member
 
Country: Other
Town: Oakley
Boat name: Zerstörer
Make: Ribcraft
Length: 5m +
Engine: Suzuki DF 140
MMSI: 235050131
Join Date: Jun 2003
Posts: 3,931
Quote:
Originally Posted by Nos4r2 View Post
I've sorted that out now-it had a hairline crack in the plug cap.

You could do a lot with that !!!
__________________
https://www.xfire.com/download/
Biggles is offline   Reply With Quote
Old 09 February 2007, 08:22   #8
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
Matt, some years ago we trialed a couple of outboards before deciding which to buy. The first was an older Yamaha 4 hp short shaft with a solid prop. It only just managed to push an Osprey 5.25 at a couple of knots and each time a wave passed under the boat when motoring into the waves the prop would ventilate as it was lifted to close to the surface (it was mounted directly on the transom). The propellor was quite a bit smaller than the later engine and in addition the short shaft didn't reach down enough to be in clear water, instead the prop was sitting behind the transom.

The second engine was a later Mercury 5hp long shaft with through hub exhaust. This easily reached down under the transom and with the bigger prop was able to give a consistent 4-5 knots. Although it had a built in fuel tank of about 1gallon, it could also be connected to a red tank and came fitted with a tap to switch between the two, a major advantage if you have to motor any distance. Since it drove the rib quite well I opted for this one. However a long shaft aux is can be difficult to store and as Matt said the Searider hulls are quite narrow. Mounted directly on the transom chances are a long shaft aux will drag in the water even when tilted.

Some suggestions, consider using an aux bracket, it might give you more room on the transom, however despite the manufacturers claims they do look a little flimsy to permanently mount an aux on. Seen some ribs with a modified seat back rest supporting the aux mounted vertically, looks neat, takes up little room and is much more secure.

Given the journey you are planning, I would strongly consider a larger outboard, but could you borrow one first to try out first?

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 09 February 2007, 12:14   #9
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,054
RIBase
I've got a short shaft 3hp Seagull here if you want to try it Matt-Seagulls may be out of the ark but are better at pushing you along at displacement speeds than most other small aux's IMO.

It's too wide at the petrol tank to fit on my 4m alongside the engine -there's only about 30mm in it-but it might fit yours.
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 09 February 2007, 12:18   #10
RIBnet supporter
 
bedajim's Avatar
 
Country: UK - England
Town: Rutland
Length: no boat
Join Date: May 2006
Posts: 2,500
Hi

I made this bracket for my 4 m sr and had a 5hp yam long shaft on it. I used to tie it to the A frame top and bottom too

Never had to use it but used the oars the only time I didn't take it

James
Attached Thumbnails
Click image for larger version

Name:	aux-1.jpg
Views:	204
Size:	107.2 KB
ID:	24799   Click image for larger version

Name:	aux-2.jpg
Views:	234
Size:	114.5 KB
ID:	24800  
__________________
bedajim is offline   Reply With Quote
Old 09 February 2007, 12:35   #11
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,054
RIBase
Quote:
Originally Posted by bedajim View Post
Hi

I made this bracket for my 4 m sr and had a 5hp yam long shaft on it. I used to tie it to the A frame top and bottom too

Never had to use it but used the oars the only time I didn't take it

James
Sods law

IT looks like your A-frame is a lot stronger than mine-and possibly Matt H's too. The brace from it is a good idea.
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 09 February 2007, 12:43   #12
RIBnet supporter
 
bedajim's Avatar
 
Country: UK - England
Town: Rutland
Length: no boat
Join Date: May 2006
Posts: 2,500
Quote:
Originally Posted by Nos4r2 View Post
Sods law

IT looks like your A-frame is a lot stronger than mine-and possibly Matt H's too. The brace from it is a good idea.
Yep it was 4 mm stainless tube we had a some at work/ the braces really made it steady
__________________
bedajim is offline   Reply With Quote
Old 09 February 2007, 13:41   #13
Member
 
Country: UK - England
Town: Bristol
Make: Ribcraft
Length: 5m +
Engine: Yamaha
Join Date: May 2006
Posts: 4,299
that looks superb, really good, ive measured mine and there is no way it will go on, im going to retain the original searider a frame, which leaves nil space!!
even a aux bracket will not fit,!! bugger!! time for a re think!!
Attached Thumbnails
Click image for larger version

Name:	IMG_0412.jpg
Views:	256
Size:	98.4 KB
ID:	24802  
__________________
matt h is offline   Reply With Quote
Old 09 February 2007, 14:11   #14
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,054
RIBase
It is a bit tight looking at that! Is there not room to fabricate an adaptor plate to fit a home-made aux bracket to the A-frame mount?
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 09 February 2007, 14:23   #15
Member
 
Country: UK - England
Town: Bristol
Make: Ribcraft
Length: 5m +
Engine: Yamaha
Join Date: May 2006
Posts: 4,299
this weekend im going to look at that idea!! reckon thats the only option, we have got so much snow here, i cant get to the boat!! anyway, just bought my self a Gecko helmet, ive really needed one!! so looking forward to that arriving!!
__________________
matt h is offline   Reply With Quote
Old 09 February 2007, 15:11   #16
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
Quote:
Originally Posted by Nos4r2 View Post
I've got a short shaft 3hp Seagull here if you want to try it Matt-Seagulls may be out of the ark but are better at pushing you along at displacement speeds than most other small aux's IMO.
Agreed have a 5hp Silver Century long shaft which pushes 2 tonnes of Old Spice at 3 knots. Also have this one kicking around the garage looking for a good home, short shaft 5 hp silver century.

Pete
Attached Thumbnails
Click image for larger version

Name:	F121424_1.jpg
Views:	221
Size:	210.9 KB
ID:	24805  
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 09 February 2007, 16:14   #17
Member
 
Country: UK - England
Town: Bristol
Make: Ribcraft
Length: 5m +
Engine: Yamaha
Join Date: May 2006
Posts: 4,299
that looks a work of art!! superb, keep hold of it and in 50 years or so would be worth loads!!
__________________
matt h is offline   Reply With Quote
Old 10 February 2007, 19:24   #18
Member
 
Country: Ireland
Length: 5m +
Join Date: Nov 2006
Posts: 90
I also am having a problem trying to fit my Aux on a Valiant 4.9, there is nowhere for the Aux bracket, does anybody carry their Aux on board and how do they carry it. Wouldnt it be difficult to fit on the transom or bracket while the boat is rolling while stopped at sea, even very dangerous?
__________________
davis is offline   Reply With Quote
Old 10 February 2007, 19:35   #19
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
Depends how heavy an outboard you have I suppose. A 10 Hp Mercury is going to weigh 30 kgs, but a 3.5 hp Tohatsu/Merc/Johnson is only 12 kgs and that Seagull above is 19 kgs, easy enough to carry with one hand.
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 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 21:05.


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