Reply
 
Thread Tools Search this Thread
 
Old 24 December 2005, 23:47   #1
Member
 
Country: UK - Scotland
Town: Houston
Boat name: Candy
Make: Valiant 490
Length: 4m +
Engine: Yamaha 50hp 4stroke
Join Date: Dec 2005
Posts: 43
High thrust. Good or Bad?

A few questions guys. Ive got a yamaha 50hp 4stroke high thrust fitted to a valiant 490. Is this a good engine for my boat or would I be better with a normal 50hp? Also what top speed do you think I can get? Just fitted the gps but not on the water till march to do a top speed reading. Thanks in advance guys. Jieboy. P.S Merry Christmas to all.
__________________
Jieboy is offline   Reply With Quote
Old 26 December 2005, 09:21   #2
Member
 
Country: Belgium
Town: Kluizen Ghent
Boat name: Spirit
Make: Ribtec
Length: 6m +
Engine: 90HP Honda
Join Date: Nov 2004
Posts: 28
Jieboy,
high-trust engine setup is just good for pushing heavy loads i think.(i have see a 50hp Yam 4stroke on a sailing boat)
With such a engine you are unable to get high top-end speeds.It al has to do with the gear ratio in the engines gearbox.
__________________
Ribfisher is offline   Reply With Quote
Old 26 December 2005, 09:38   #3
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: 13,069
RIBase
You'll be able to change top-end speed by changing prop. The High thrust engines have bigger props than normal so if what I've seen of them is typical you'll get a lot better holeshot than with a normal engine-my sr4 with a standard 50hp got walked over on holeshot by a 17' fishingboat with a 60hp bigfoot mariner as he was getting less slip.
__________________
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 26 December 2005, 16:01   #4
Member
 
Country: Ireland
Town: Dublin & Enniscrone
Boat name: K'adó
Make: Redbay
Length: 7m +
Engine: Suzuki 300
Join Date: Oct 2004
Posts: 613
High thrust

Hi guys

Did you read the yamaha brochure before you bought ??

I have 6.5m Redbay , 200hp v6, fuel capacity approx 230 litres , plenty of safety gear and i suspect about 3x weight of your valiant . i am considering a 9hp high thrust as an auxillary.

Don't waste your time fitting the engine unless you are thinking of getting a trawler or tug license.

Rgds
__________________
Take it easy ....but, take it all the way.
Ezgoing is offline   Reply With Quote
Old 26 December 2005, 16:10   #5
Member
 
Country: UK - Wales
Town: swansea
Boat name: Too Blue
Make: BLANK
Length: 8m +
Engine: Suzuki DT225
Join Date: Mar 2004
Posts: 12,791
Quote:
Originally Posted by Jieboy
A few questions guys. Ive got a yamaha 50hp 4stroke high thrust fitted to a valiant 490. Is this a good engine for my boat or would I be better with a normal 50hp? Also what top speed do you think I can get? Just fitted the gps but not on the water till march to do a top speed reading. Thanks in advance guys. Jieboy. P.S Merry Christmas to all.
Contact a prop specialist - someone like steel developments - you should be able to get a good result with a higher pitch prop than normal.
__________________
codprawn is offline   Reply With Quote
Old 26 December 2005, 17:10   #6
RIBnet supporter
 
bogib's Avatar
 
Country: Iceland
Town: Reykjavik
Boat name: Cheesee
Make: Seaquel 600 XS
Length: 6m +
Engine: Mercury 275 Verado
Join Date: Aug 2003
Posts: 1,959
Send a message via Skype™ to bogib
With right prop. you should gain similar speed as I got

see here: http://rib.net/forum/showthread.php?t=12484&page=1&pp=4 post#4

Bogi
__________________
RIBs and ribbing is my life
www.sjosport.is
bogib is offline   Reply With Quote
Old 27 December 2005, 00:27   #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
I got a 50 HP Yamaha High thrust on my 4 mtr searider. it does 33 Knots + and fuel consumption is good. Acceleration is out of this world. It came with a 11 inch prop but they gave me a 15 inch prop and that goes well. Probably a 14 inch prop would be best.

Only bad point is it gives off a bit of a rooster tale.

I bought it because it was the right price. I knew what High thrust meant but second hand I just couldn't find a normal 50 HP last summer at anywhere near the right price.

I really don't have a problem with the High thrust and because its pretty new I would be prepared to put it on a 5.4 mtr searider.
__________________
Biggles is offline   Reply With Quote
Old 27 December 2005, 13:49   #8
Member
 
Country: UK - Scotland
Town: Houston
Boat name: Candy
Make: Valiant 490
Length: 4m +
Engine: Yamaha 50hp 4stroke
Join Date: Dec 2005
Posts: 43
Biggles, so your saying that you get very good acceration with a good top end aswell? Sounds good to me. Think ive got a 15 prop on mine,might try a 14.
__________________
Jieboy is offline   Reply With Quote
Old 27 December 2005, 14:19   #9
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
Jieboy,

I don't have an issue with the engine. Its been good so far. Ideally I would have got a normal 50 HP but :-

When i wanted one during the summer a) I couldn't find anything half decent and b) this engine came along at a very good price.

Weight has been a bit of an issue with the boat but I've done well over a hundred hours with it in all sea conditions and I haven't sunk yet ! All the 50 HP 4 strokes PTT are probably a bit heavy for the Searider 4M.

Regards Nick R.

Any thing i can help you with info wise please let me know.

I just got mine serviced for Ł80 plus parts and will be getting back out on the water later in January.
__________________
Biggles 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 01:39.


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