how much power?

minisponger · 27 November 2018, 10:13

Hi guys
i currently have a very old Avon s250 sportboat, running a tiny 4hp outboard. it says on the transom plate it is rated to 25hp but has useful hp of 15. if anyone knows anything about these old SIBs is it worth me getting a 15? would the performance over a 10 be worth it? I'm very undecided as with the extra weight and fuel costs on one hand but obviously on the other there is MORE POWER! how much does it take to get one of these to plane? I'm not a small guy, certainly lighter than a friend who goes out with an excel boat of a similar length, and he gets on the plane very easily with a 10...

Ribtecer · 27 November 2018, 10:39

Welcome Sam.

I have an Avon Rover 310 with a wooden floor and that flies with my Tohatsu 9.8. Actually I think it would be dangerous with another 50% power.

Just my view.

minisponger · 27 November 2018, 11:08

that was another of my concerns, its a very old boat after all...

jeffstevens763@g · 27 November 2018, 14:40

I had a 15 on a zodiac zoom went like a dream just because you have 15 horses doesn't mean you have to use um throttling back is better for fuel consumption and the engine it's rated to 25 so plenty of strength in the boat, great boats avons.

minisponger · 02 December 2018, 09:32

thanks very much guys!
i think i'll just wait until the right engine of either size comes up at the right price. Or find a way of convincing the Mrs to let me buy a new one

Seaflyer02 · 02 December 2018, 16:33

A friend of mine had the S250 with Evinrude 25. The boat was only rated at 25hp if you had the remote steering and controls if I remember correctly otherwise 15hp tiller was max. It did go well though!

Seaflyer02 · 02 December 2018, 18:37

9D280 · 20 December 2018, 16:40

Quote:

Originally Posted by Seaflyer02

A friend of mine had the S250 with Evinrude 25. The boat was only rated at 25hp if you had the remote steering and controls if I remember correctly otherwise 15hp tiller was max. It did go well though!

I get the wheel / tiller thing - get the weight forward!

Here is a curveball Q.... I've got a W300... which i believe is the "robust" (read: industrial so heavier?) version of the S series... it is also rated for 25 but no mention of a wheel...

I'm typing this from memory, so be aware my "W= heavy" theory might be a figment of my imagination!

pagick · 21 December 2018, 02:01

Quote:

Originally Posted by minisponger

Hi guys

i currently have a very old Avon s250 sportboat, running a tiny 4hp outboard. it says on the transom plate it is rated to 25hp but has useful hp of 15. if anyone knows anything about these old SIBs is it worth me getting a 15? would the performance over a 10 be worth it? I'm very undecided as with the extra weight and fuel costs on one hand but obviously on the other there is MORE POWER! how much does it take to get one of these to plane? I'm not a small guy, certainly lighter than a friend who goes out with an excel boat of a similar length, and he gets on the plane very easily with a 10...

My first sib was a 1985 Avon spitfire. 30 hp max and that’s what I had on it. Back then the motor weighed 116 lbs. and it was designed to take controls that just clipped on it. The tiller handle that you just pushed up when using steering setup. It was blazing fast but less with two. Just ok with 3 and would barely plane with 4+ so I’m a believer in more hp is more fun.
My second sib was a small 12’ with a 20 hp. Fast with one. Slow with more. With 3-4 it’s a displacement hull.
P.s. I just looked at your pic again and that’s the same engine only smaller. Great design having both tiller/ remote control.

minisponger · 18 March 2019, 08:31

Quote:

Originally Posted by minisponger

thanks very much guys!
i think i'll just wait until the right engine of either size comes up at the right price. Or find a way of convincing the Mrs to let me buy a new one

So I've ended up with a 15! Now just to wait until the weather improves so I can give it a go! Pictures to follow when I can get going on it. When the summer comes I'd love to have a play around with some more people in different places so hopfully I'll get out and about for a bit of proper boating!

jonp · 19 March 2019, 00:14

I've always found the recommended hp manufacturers state to not be enough for me and always wish I'd gone to the max they recommend.

Pikey Dave · 19 March 2019, 06:49

Quote:

Originally Posted by jonp

I've always found the recommended hp manufacturers state to not be enough for me and always wish I'd gone to the max they recommend.

A man after my own heart[emoji106]

pagick · 19 March 2019, 14:55

If you can solve the weight and cost, more is better. IMO
https://youtu.be/0-l-Rvu8ZfI

jeffstevens763@g · 19 March 2019, 16:33

Quote:

Originally Posted by pagick

If you can solve the weight and cost, more is better. IMO
https://youtu.be/0-l-Rvu8ZfI

back to the good old days engine coughing loads of sh-t out no safety gear personal positioning love it thanks for posting