engine advice needed

[Clarky021]

We have a 2015 zodiac 2.7 air deck inflatable and have been running a borrowed 1997 Honda bf5 hp on it but are looking to upgrade the engine and looking for advice with a view to buying soon.The boat has a max rating of 6hp on it so I'm guessing you can't exceed that? Or can you within reason?
I need something that's not too heavy as I have to carry the engine at times so weight is an issue and I can just about manage the Honda bf5.
Also how much better will a modern 5 or 6hp engine be than our old Honda bf5? And how much better performance would we notice?
Would appreciate any advice on what would be best engine to seek out,

[Akira]

Hi Clarky,

If your Honda BF5 is a 4 stroke, it's weight will be exactly the same as the modern one. If this is a 2 stroke, the modern 4 stroke will be about 10-20% heavier.

Regarding the excess of the horse power on your inflatable, it is all about the insurance. Physically speaking, your boat can probably handle an 8 HP but if the boat is rated 6 HP only, any excess will invalidate your insurance. If you don't mind, try a bigger one. My boat is rated 20 HP but I run a 25 HP on it and will update it to 30 HP soon.

A modern 5-6 HP will push your boat with 2 people at about 5 knots, which is below the planning speed, so 5hp or 6hp will not really make big difference.

I was on a 12 ft inflatable with a friend, powered by Honda BF5 and the only times we could get on plane was when the river cruising boats passed behind us, creating a lifting wave

If you want some more power and less weight, the only option is a 2 stroke 6hp, you can get one for not expensive on eBay

[Fenlander]

>>>If your Honda BF5 is a 4 stroke, it's weight will be exactly the same as the modern one.

Well yes... but...

A Honda BF5 weighs 27kg. A 6hp modern Suzuki weighs 3kg less. So if Clarky can just manage the Honda the Suzuki would be slightly easier to carry and with 20% more power.

[jeffstevens763@g]

Originally Posted by Fenlander

>>>If your Honda BF5 is a 4 stroke, it's weight will be exactly the same as the modern one.

Well yes... but...

A Honda BF5 weighs 27kg. A 6hp modern Suzuki weighs 3kg less. So if Clarky can just manage the Honda the Suzuki would be slightly easier to carry and with 20% more power.

Is that the newly launched Suzukis David because they launched lighter low hp models not long ago 4-5 months?

[ashtonmarine]

Hi

all honda outbaords are 4 stroke so yes the NEW Suzuki is 24 kg is the outboard most people want as you can put it down on either side. I would also not go above that as all 8hp are heavy lumps being twin cylinder engines.

The other thing though to think about is balance. on all small boats this will effect speed by a huge margin so move things/ people around to get the most out of it!

Dave