Avon 4m Speed

[Suzuki416]

Oh,
Bilge Rat & Phil...

Nearly forgot.
Just got a brand new prop (used once) for my RIB so I can go FASTER
Its a S/S Ballastic 13 1/2 x 17 (paid £90)
Will have it at RIBEX

Pete
Just wanna go faster!

[ollyit]

A lot of usefull information there - espcially bilge rats contribution
bugger forgot to notice that potentially spare motor was halfway across the world - that'll learn me!

[Bilge Rat]

Suzuki may i ask where you bought this prop from ? 17 inch pitch on a 70 seems fairly small considering i'm running a 19 on my 50 am i over pitched ? all thoughts say not and i've even been told by Steel Devs that i could go up to a 21....thats if they could source one for me cheaper than a new engine, seems my size 11-1/2x19 is an odd size, they can get them in both stainless and ali but the stainless was £311+VAT and the ali was approx half that price

Suppose its just this engine having yet another laugh at me again !!

I did though speak to Highway Marine at Sandwiche 2 days ago and they say they can get me a 11-1/4x19 ali for £103+VAT but i'd have to go in and pay for it before they ordered it in...... from all my research i've not been able to sourse one and steel devs would have to bring it in from Belgium for me, so why do Highway believe they can get one ? might go in tomorrow and buy/order it just to see if they can actually get one in !! they are an Evinrude main dealer/service agent so maybe they have the direct contacts ?

One other thing.....how much difference would 1/4 inch less diametre make to performance ?

[Suzuki416]

Originally Posted by Bilge Rat

Suzuki may i ask where you bought this prop from ? 17 inch pitch on a 70 seems fairly small considering i'm running a 19 on my 50 am i over pitched ? all thoughts say not and i've even been told by Steel Devs that i could go up to a 21....thats if they could source one for me cheaper than a new engine, seems my size 11-1/2x19 is an odd size, they can get them in both stainless and ali but the stainless was £311+VAT and the ali was approx half that price

One other thing.....how much difference would 1/4 inch less diametre make to performance ?

Bilge Rat,

I am 'pushing' a much larger prop 13 1/2 vs 11 1/2.
The pitch is going to be on the upper size side for this engine.

How I'm working these prop sizes is...
assuming calm conditions

Can I reach max rpm light (me & fuel)?
if not - Over proped

Can I reach max rpm heavy (3 people & fuel)?
if yes, can maybe drop a pitch to help acceleration

Does it take a long time to get on the plane when heavy? (take the bung out!!! easy way to test heavy - )
if so also may be overproped (or too many burgers & beers in the cool box)

Also I still don't know my rpms yet so true test CANNOT be carried out.
Pete

[Bilge Rat]

Originally Posted by Bilge Rat

Hey Suzuki......maybe your not as mad dog crazy as i had first thought

Nope i take this one back......your now back up to being mad dog crazy again Suzuki

God i've gotta get one of those onboard fridge freezers !!

[Searider]

Originally Posted by Brian_Pal

I have a Avon Searider 4m with a Honda 45 hp 4 stroke on it right now. The engine is in the shop for repairs, and depending on how severe it is, we might just sell the engine. A friend has a 2 stroke Yamaha 50 that he bought new last year, and used for a few months. Now it's just sitting in his garage, and was thinking of possibly picking it up for my 4m.

What would be a good price to offer for a good used yamaha 50? Would it make my RIB faster, and if so, by how much? I know some of you have 2 stroke 50's on your seariders, how fast do they top out at? How much more fuel would it use? Would it be a lot louder than the Honda?

Thanks!

Brian Pal

Brian,

My first RIB was a 4m Searider with a 50hp manual start Yamaha and it was fantastic!
Would do about 39 knots in the flat and was not unstable - well maybe just a bit. Mine was the version with the four back to back seats and although there was a bit of chine riding as I was held in a seat it didn't feel too bad.

As to fuel I usually carried two 25 litre cans. One in the stern and one in the bow. The one in the bow had a long pipe so there was no need to move them around. With fuel as cheap as it is in the US who cares how much it uses?

I had two propellers. The one it came with was a bit small and the engine sounded like it was revving very high so bought a bigger one - this was the one that gave the top speed. Made it difficult to get on the plane with four on board but was perfect with two on board.

I would say if the cost of the repair to your Honda is anywhere near what your friend wants for his Yamaha go for the Yamaha.

Duncan

[nines]

Hi
I have an Avon 4m SR with Mercury 2-stroke 50 (elec start & trim). It is my first rib (bought from badbaws 18 months ago) and is fantastic! With me and one other on board it will happily reach 35+kts on calm water. Don't know how that would compare to the Yamaha but certainly suits me fine. I have just added a second 25l fuel tank - like Duncan one is in the bow, one in the stern and both connect with the same long fuel line. That was done so I can stay out longer/travel further. Although this is my first rib and I have nothing else to compare it with, I could not be happier - it does fine for pottering around Poole Harbour as well as some eye watering speedy stuff too. Doubt this will help with your decision but just wanted to contribute to the "how great seariders are" line...

[Brian_Pal]

Originally Posted by Searider

Brian,

My first RIB was a 4m Searider with a 50hp manual start Yamaha and it was fantastic!
Would do about 39 knots in the flat and was not unstable - well maybe just a bit. Mine was the version with the four back to back seats and although there was a bit of chine riding as I was held in a seat it didn't feel too bad.

As to fuel I usually carried two 25 litre cans. One in the stern and one in the bow. The one in the bow had a long pipe so there was no need to move them around. With fuel as cheap as it is in the US who cares how much it uses?

I had two propellers. The one it came with was a bit small and the engine sounded like it was revving very high so bought a bigger one - this was the one that gave the top speed. Made it difficult to get on the plane with four on board but was perfect with two on board.

I would say if the cost of the repair to your Honda is anywhere near what your friend wants for his Yamaha go for the Yamaha.

Duncan

Hey,

Your boat sounds almost identical to mine. The fuel hose is long enough to reach the bow area where I can put the 5.5 gallon tank when I've got it loaded with people for better weight distribution. when it's just me or two of us, I put it in back for more room. How much fuel did you use with the yammie? Thats the thing I like about the Honda- good fuel economy- but being a teenager, speed is more important than money

Thanks for the replies guys! We'll see what happens, but the Yammie sure sounds fun!

[Brian_Pal]

Originally Posted by Searider

With fuel as cheap as it is in the US who cares how much it uses?

It seems really expensive to us, I am where it's the 3rd highest in the nation right now, but I can't imagine paying what you guys over in Europe pay!!!

People complain constantly, and I always tell them that at least we don't live in Europe, or have to bike!

[Searider]

Originally Posted by Brian_Pal

Hey,

Your boat sounds almost identical to mine. The fuel hose is long enough to reach the bow area where I can put the 5.5 gallon tank when I've got it loaded with people for better weight distribution. when it's just me or two of us, I put it in back for more room. How much fuel did you use with the yammie? Thats the thing I like about the Honda- good fuel economy- but being a teenager, speed is more important than money

Thanks for the replies guys! We'll see what happens, but the Yammie sure sounds fun!

Can't remember how much my 50 used but it was bearable. It is often said that a four stroke will use 40% less but can't confirm this.

How much are you paying for fuel on the dockside there. I bought some this morning for 99p per litre. Ouch.

[Brian_Pal]

Ummm, not exactly sure what it is right now, around 2.79 US per gallon though. Startung to get up there. I rememeber paying 1.40 or so...

[Brian_Pal]

Well, we went and looked at the Yamaha today. It is about 4 or so years old, and is a 55 hp 2 stroke. It was winterized when taken off the boat about 2 years ago, and has been sitting covered since.

Does anyone know if this is the same transom weight as the yamaha 50? Would a 55 be too much for my 4 meter? 5 hp is a lawnmower, so I doubt it would be too insanely much more?

The guy wants between 1700 and 1900 American for it. Do you guys think this is a good deal? It is basically broken in, has 15 maybe 20 hours on it.

It does not have power trim or tilt that I can see, is this a big disadvantage?

Thanks!

Brian Pal

[Brian_Pal]

TTT, anyone?

[Brian_Pal]

One more time!