8hp Enough for a 3.4m SIB?

Flyguy · 04 December 2008, 08:31

Hi Guys. I've just become a proud owner of a Zodiac CFR 340 ACTI-V and now looking for a suitable lump to stick on the back. However the boat will be used for fishing and typically self-launching so I need an engine I can lift and fit myself.
I'm looking at a Yam F8C (37kg) and don't want anything heavier but I'm not sure how the 340 will cope with this 8hp engine?
Decent condition 2-strokes seem rare now.

Any thoughts, feedback or ideas would be appreciated.

Thanks..

J S · 04 December 2008, 09:19

Iv got a 15hp Honda (46kgs) on the same boat, With 15hp you can have 4 people in the boat and still get up on the plane without stressing the engine and still cruise comfortably without stressing the engine.

Im sure an 8hp would cope fine for up to 2 people but you would really appreciate the extra power if you ever hit any weather for example on bar entering an estuary with big following waves allowing the extra power to get you away from danger.

Even with a 15hp you can have a full day out on £10 of fuel covering many miles.

Hope this helps a little

James

John Kennett · 04 December 2008, 09:36

The 8hp will be OK, but you'll probably find you want more.

If that's as much as you reckon you're happy to lug around, then stick with it though. If you buy a bigger and much heavier engine then launching may become too much of a chore and you'll end up using the boat less.

I would try to find a decent used 15hp 2-stroke if you can.

John

Flyguy · 04 December 2008, 09:51

Thanks chaps. I have been looking for 2-strokes but they seem to be rare now, in condition at least. Do you know of any sites or dealers that still have stock?

Vintec · 04 December 2008, 10:40

Well if you can find a decent 2 stroke, 15 hp will be around 36 kg.
The lightest 4 stroke is indeed around 46 kg.
Depending on how you are going to launch, up to 50 kg should be ok to carry.
But if you're going to launch with wheels on the transom, then 46 kg or even 60 kg is no problem what so ever.

I've had 15 hp behind my sib, and long ago also 6 and 8 hp, and with 15 hp you'll find yourself always with some extra power, which you just don't have with the smaller engines. Think you'll regret it if you go for less then 15.....

Locozodiac · 04 December 2008, 12:15

Quote:

Originally Posted by Flyguy

Hi Guys. I've just become a proud owner of a Zodiac CFR 340 ACTI-V and now looking for a suitable lump to stick on the back. However the boat will be used for fishing and typically self-launching so I need an engine I can lift and fit myself.
I'm looking at a Yam F8C (37kg) and don't want anything heavier but I'm not sure how the 340 will cope with this 8hp engine?
Decent condition 2-strokes seem rare now.

Any thoughts, feedback or ideas would be appreciated.

Thanks..

10 & 15 HP engines weights the same, so if portability is a big issue, how about a Tohatsu/Nissan 9.8 2 strokes (just 26 Kg) if possible to find one. If planning for more divertimento/speed go for 15 then.

Happy Sibbing

Channel Ribs · 04 December 2008, 15:13

As already said, an 8 will be ok but you may wish to poke around and find a 15 two stroke. Also as mentioned the Tohatsu 9.8 2/s is a cracking engine for this size of boat.

Have you considered launching wheels? This would help you to put the boat together at the car and then wheel barrow along the slipway at ease.

MeMe · 04 December 2008, 15:52

with a yam 8hp 4 stroke on the tail - I'm 12 stone (14 really) and it would push me up on the plane without trouble, add my 12 yr old daughter and it would do the same - add another small child and gaing no worries however, add the "dragon" and it was a struggle to get our of displacemnt speeds.

However the 8hp was light, easy to handle and took up little room in the boot of a then Audi A4.

I'm with the sentiments of others re the need for speed however, an 8mtr rib owner with twin 250's will always desire more - that's life so, in my opinion as long as you are happy with the weight issue then once on the plane you'll find the 340 and 8hp combo great.

As for a 15hp - yesterday I bought a Yam 360 with a 15hp 4 on the tail - I'm a fit guy and pretty strong however, hurling the 15 around was not easy - I now have a 5 series touring and getting the 15 in was not easy - as a 2 man job it was easy but alone was a struggle.

Go for the 8 for now and do as me, upgrade at a later date if needed.

Flyguy · 04 December 2008, 16:19

I've just been down to the local dealer lifting engines

I think 8hp 4 stroke is the max I would want to lift out of the boot alone and fit onto the SIB, maybe a 9.9 at a push. If I think I will need more later the dealer said I can trade up so I will go with one of these. Thanks for all your replies.
John

MeMe · 04 December 2008, 18:08

...........the beauty of a forum, especially this one whre you'll find some extremely competent and experienced help and advice. Except from the "Gafish" who you will no doubt come into contact with if you stick around long enough.

Nos4r2 · 06 December 2008, 02:58

Quote:

Originally Posted by MeMe

...........the beauty of a forum, especially this one whre you'll find some extremely competent and experienced help and advice. Except from the "Gafish" who you will no doubt come into contact with if you stick around long enough.

I think you'll fnd gArfie makes far more sense than he should if he's being serious...

m chappelow · 06 December 2008, 21:56

i use an 8hp 4 stroke on my 3.4 sib and it does what i want it to ,but think i would go for a few extra hp .

PeterM · 07 December 2008, 11:46

Used to run an 8hp 2st Johnson on an avon 3.1 RIB - fine on flat water one or two up, anything more and it struggled. I coudl only just carry it & it had a built in handle. You could get a 10 that was the same weight , but I didn't want to pay the extra money !

No point killing yourself carry the thing - it'll put you off using it & spoil the enjoyment.

mechanic · 08 December 2008, 15:37

I agree with one of the previous replies.
Try and get hold of a 9.8 Tohatsu 2 stroke, it is light enough for me to carry in and out of my motor home, and im only 5ft 6in tall and have no problem moving it around.
Good on fuel too.

Locozodiac · 08 December 2008, 17:17

Quote:

Originally Posted by mechanic

I agree with one of the previous replies.
Try and get hold of a 9.8 Tohatsu 2 stroke, it is light enough for me to carry in and out of my motor home, and im only 5ft 6in tall and have no problem moving it around.
Good on fuel too.

As someone stated :"Also as mentioned, the Tohatsu 9.8 2/s is a cracking engine for this size of boat".

I'll second that Mechanic, mates that don't know Tohatsu thinks that a 9.8 is a 9.9,a complete error, 9.8 is the max update to same 8.0 with same CC and performs much better than any 8.0 HP. Other brands doesn't have a 9.8, next one is 9.9 younger brother to 15 HP, much heavier that a 9.8.

Happy Sibbing

Flyguy · 30 January 2009, 19:28

Just an update. I tracked down a 2004 Tohatsu 9.8/2 in excellent condition so I'm very happy and all set to go. Thanks for all the advice chaps. What would we do without the Internet eh?

codprawn · 02 February 2009, 12:59

Make sure you get proper transom wheels - best thing since sliced bread!!!

JMO · 25 February 2009, 20:20

I'd agree with the previous post - get a two stroke 15hp.

I have tried out an 8hp two stroke and a 8hp Yamaha four stroke. There is a huge difference. The two stroke gets up and goes far quicker and it also a lot lighter. The extra 15hp would allow you to get a better fuel efficiency at cruising speed and allow you to take more people and therefore have more fun!

Cheers,

Mark
www.jmoboatdeliveries.co.uk