Avon Rover 3.1 speed

Colin K · 26 February 2012, 20:25

Hello,
Wondered what sort of speed I will get out of my rib with a 15hp outboard ? Is there a rough guide as to mph per hp, and is there a formula showing kg/stones per hp needed to get on the plane. Understand that persons on board will make a big difference. She has a fibreglass bottom. Will it pull a ski biscuit ? Sorry about the questions.

All the best, Colin.

Downhilldai · 26 February 2012, 21:28

I'll be running an Avon R3.10 RIB with a 15hp Yam next weekend, weather permitting, so will be able to get you some answers then.

What age is the one you have, as earlier ones had a different hull profile?

PeterM · 27 February 2012, 12:34

Hopefully I will be too

( if I can find a couple of hours to flow coat one night this week) - but with only the 13 ish hp of the Johnson GT .

I'm hoping to see 20knts on flat water 2 up.

I think you may get away towing with it if its very flat water , if not you'll find it hard as with little weight it will get knocked about off waves very easily. I have turned the D rings outwards on the one I'm working on for just this purpose.

EnglishLes · 27 February 2012, 13:38

Quote:

Originally Posted by PeterM

I'm hoping to see 20knts on flat water 2 up.

I was also quoted 20knts for an Avon-Bombard 3.1m with a 15hp engine by someone on the Avon stand at the Southampton Boat show.

Need to get the engine running properly first though - got it as a non-runner on flea bay - now starts but haven't tried running it for long - not even sure if the fuel pump works yet!

badbaws · 27 February 2012, 16:46

I used to run a 3.1 Avon with a 10hp Mariner. I hit 20 knots on GPS 1 up.
With the extra 5hp should get about 22 knots.. I fitted duel fins for quicker planing and would plane at 5 knots!

PeterM · 12 March 2012, 12:09

Real world testing yesterday afternoon - with 'about' 13hp - 2 up - 19.4knts .

Trimmed the engine up 1 hole and more revs/noise, but not much more speed at 20.2 on the GPS .

Colin K · 13 March 2012, 18:49

Wow thanks for the feedback couldn't ask for more ! And couldn't ask for more if you know what I mean ha ha.
If I get near that sort of speed I will be a very happy bunny.

All the best,
Col.

badbaws · 13 March 2012, 19:21

I also ran two x Yamaha Maltas on a 3.1 RIB and got 16 knots... crazy stuff!