Ribtec

[Woosy]

Hello Guys,
Im new here and I am looking for some advice, I have a RIBTEC 5.8m with a Yamaha 2 stroke 90hp,the 90hp engine has been giving me trouble, I have been offered a great bargain on a Yamaha 115 v4 2stroke engine, will this engine be too heavy/ powerful for the RIB?

Thanks Andy.

[Festinghouse]

at a guess i would say power should be fine, but the yam v4 is a thirsty engine. looked at one but decided against it

[Woosy]

haha dont care about the fuel as long as the back of the boat doesnt get ripped off and sink!

[Kernow Buoy]

115 will be fine, I've got a 150 Opti on mine!

[Woosy]

Happy days, ... however it does have a plate on the back saying recommend hp 90! Thanks for the quick replies by the way guy

[Kernow Buoy]

Originally Posted by Woosy

Happy days, ... however it does have a plate on the back saying recommend hp 90! Thanks for the quick replies by the way guy

Hang on that doesn't sound right, my 5.35 Ribtec was rated to 90hp
Ribtec 5.85's were rated to either 120 or 150 depending on year of manufacture.Sure your's is a 585?

[Woosy]

Maybe mine is a 5.3 then? yikes!!

[Kernow Buoy]

Originally Posted by Woosy

Maybe mine is a 5.3 then? yikes!!

could be! got any pic's?

[Woosy]

Trying to upload a couple now but im overseas and the net is rubbish! i will keep trying, thanks mate

[Ribshop]

The early 585s were rated to 90hp later it was changed to 130. When I worked for Ribtec we rigged loads with the Yamaha 130V4 and they went very well.

[Woosy]

Thanks Ribshop, So they must have strengthened the transom on the later models?

[Kernow Buoy]

Looking on your profile pic's you have hull number 94184 which is the 184th boat of 1994. I had a 1995 5.35 rated to 90hp and my current 1995 5.85 is rated to 120 hp, looking at your other pic I'm pretty sure that's a 5.35. The hull is the dead giveaway -
white hull one is a 535, and the neapolitan is a 585!

[Swain Marine]

Yes looking at the profile pic it looks the same size as my 535

[Woosy]

ok guys, so, i have figured out that my boat is actually a 535 not a 585.. duh, my bad! so i guess the good deal offered on the Yamaha 115 is not going to work? or does anyone know if it possible to strengthen the transom?

[Kernow Buoy]

Yes it's possible, transom knees can be added reasonably easily but your question really is should you, a well sorted 90 will push your 5.35 to 40kts and IMVHO that's pretty much it for the hull (mine would start to chine walk quite strongly at 40kts) there was no way I would have wanted to go quicker. The extra weight may well upset the balance of your boat rendering more of the 115 horses unusable, there's also the insurance implication of having an engine exceeding the manufacturer's spec. Finally if you'd asked which engine to fit I'm guessing the most popular reply would be a Yamaha 90 they are very highly regarded and seem to be Ribnet's engine of choice for a 5.4 rib! Might be worth investigating your troublesome one a bit more?

[biffer]

Stay with the yam 90. It's a nice little setup

[Ribshop]

That is a 535 and dont go any bigger than the 90 with the 115 it will handle like a dog. And you are boat 184 not 184 of 1994.

[Woosy]

Great advice and thanks very much, the marine mech who is meant to be fixing my engine cant find the problem why its not running on full power, so he sugested that I find a newer engine, I might take else where, thanks again Andy

[Woosy]

Thanks to you all for the advice,
Here is what im going to do, wait till I get back to the UK and take my boat somewhere else for a second opinion, there is another boat yard on Anglesey I can try. just want it sorted its not worked since last summer, frustrating!

[poulner6]

I have a Ribtec 655 with a 150 HPDI