under powered or not

[Gold_can]

I am currently looking at purchasing a new toy (5.5 Joshua Center Cab), at the moment I am looking at putting a 115 Yamaha 4 stroke on the back of her.
Does it sound like it will be under powered on not?
Does anyone out there have one of these boats with a 115 on the back, what is the performance like?
Cheers

GC

[joey_1987]

I went to the Joshua boats website but couldn't find any info on HP ratings for the hull, they only have some pictures on there in the boats section. I just had a read of some reviews of 115hp 4 strokes and 115hp DI 2 strokes, and they were mostly on hulls around 5.5m long and gave performance in the 65-70km/h range at top speed, so I would say not really underpowered. Have a read about the 115hp's and the hulls they were tested on for yourself http://boatpoint.ninemsn.com.au/portal/alias__boatpointau/tabID__200859/ArticleID__119833/DesktopDefault.aspx
Cheers, Joey.

[Alex9797]

Hey Gold Can,

welcome to the madhouse ;D

IMO I don't think that it would be underpowered. I had a good look at these boats not long ago and given the design of the forefoot and the slightly lower weight being alloy I would think that it would be a reasonable match.

I guess it all depends on how much weight you intend to carry, what you use the boat for and whether you prefer speed over economy. Do you know what the hull weight is?

I really do not know a lot about the virtues of one outboard brand over another but would assume that the motor would be very economical compared to mine ( a six cylinder efi merc )

certainly nice people to deal with at JBS.

happy shopping

Alex

[Alex9797]

Sorry forgot to add that I was of the understanding that the jbs hull was designed for efficientcy (%^$ spelling) rather than all out speed so having a large engine on the back may be a bit of a waste. I hope I've got that right. :-?

cheers

Alex

[Gold_can]

Alex,
Yes I would have to agree they are a fantastic bunch of people to deal with, I turned up at the workshop on a Friday late afternoon,pretty close to knockoff time and probably spent an hour and a half could have been even more and they were so receptive to all my questions that I had they also let me have a squiz around the workshop to have a look at the 5 or 6 boats that they had in various stages of construction.
It was this kind of service that has got me sold on one of these rigs, but I will have to wait until the end of the year when I return back to oz before I purchase one of these beauties.
As for the hull weight I think off the top of my head it was around the 700kg mark.

[pilchardjones]

hi gold can,
i have a 6m goldstar plate boat with a 115hp 4 stroke yamaha / 15P SS 4 blade solas prop. not sure of exact weight but it has 5mm bottom and 4mm sides so i would think 800kg or more.
i get 32mph top speed and cruise on around 22 mph. i am more than happy with this performance. i just run to the reef from townsville and don't have to contend with a bar.
IMHO the motor will be a great match for your proposed boat. the 115 yamaha 4 str is a superb engine. so quiet and smooth and efficient. i love it.
good luck with the purchase. it will be a very nice rig.
steve

[gawby]

Mate,
I have just bought a yalta (6M) and have a 115 yamaha 4/s on it and it performs more than good enough.
I don't thonk you will have any problems.
I would have prefered about 130hp but they don't make it and the 150hp would have been overkill.
Graeme ;)

[yalta]

does'nt really matter what you put on... ....prop choice is more important.

[ahoj]

Nice boats-- expensive ---fuel is dear----- Hmmmm

Ahoj

[poss]

Gold Can

I have a 5.5m J.B.S. c/console 2yrs old dont go any lower than 115hp these size boats can take up to 140hp 4strokes 115 would be a great match with this type of hull.
poss