Used RIB Values

paulford · 15 March 2003, 16:32

How does one establish a realistic value for a used RIB? I assume that if both RIB and Engine are the same age, then it's simply a matter of costing the replacement new cost out and applying straight line depreciation over the age of the boat?

However things become more complex I suppose when the boat is 8 years old and the engine just 12 months.

I'm currently being threatened with a '95 Ribtec 5.85 fitted with a new Suzuki 140 4 stroke engine in May of 2002. Riding on a single axle Hallmark trailer and having a basic electronics setup.

Would probably cost c£19k all in today, possibly a dribble less.

Does £10k sound realistic? Judging by all the advertisements of boats for sale I've seen it sounds on the high side - but that Suzuki lump would have cost a few quid last year, and has only done about 25 hours.

Obviously any glaring faults or excessive wear will impact on the value to the cost of the repair.

Any real world views would be welcome.

Can't comment on boat condition as yet, although I'm hoping to go and see it tomorrow (Sunday 16th March).

Alan · 15 March 2003, 17:14

A rule of thumb (IMHO of course) is that the older a RIB gets the more the price / value of the engine becomes important. I would guess that a new Suzy 140 4 stroke has gotta be £6-7k ish? so £10k incl trailer sounds like a good deal. Providing of course the RIB itself is in good condition. My only caution would be that I imagine the 140 4 stroke is a heavy old engine for a relatively small RIB.

Alan

paulford · 15 March 2003, 17:57

Suzuki 140 4 Stroke is 186Kg, actually marginally lighter than say a Yam 115 4 stroke, but as you rightly say 20Kg heavier than a Yam 130 2 stroke.

Running costs don't worry me too much, but 2 strokes are, generally speaking thirstier than a 4 stroke of similar output aren't they? Unless of course we start talking about the high tec 2 strokes - Optimax and the like.

I may end up ordering a new boat if I don't find what I want used, and then I'd go for twin 60 or 70HP four strokes - Yamaha seem to be better on power to weight than Suzuki for that sort of output.

Paul

Pete7 · 15 March 2003, 18:32

Paul,

this is going to cause some interesting posts but what the hell lets go for it.

There is a belief that 4 strokes are more fuel efficient that the old two strokes. Indeed until recently I too believed the manufactures advertising. Until that is I had a chance to a simple test in the real world, eg out on the water.

Boat one: Standard Camel boat, eg Ribtec 6.5m with Honda 130 hp 4 stroke. Boat two, Ribtec 6.45 with Mariner 150 V6 two stroke.

So how much fuel do they use? The camel boat uses 45 lph at a good lick, 30+ knots. The Ribtec with the V6, 40 lph (I will conceed the need for two stroke oil as well). So is there a difference in the boats to explain this ? well yes the Camel does have a big frame which is neither light nor aero dianamic, but it was tested with one person in it. The Ribtec with the V6 had two full fuel tanks and had five divers plus there kit in it.

So what does this show, well there might be savings at certain speeds, say at tickover, but if its a saving of 30% when you are using 5 lph so what, the amount you would save over the course of a year is hardly worth shouting about unless you really are doing an awful lot of slow speed stuff.

The 4 strokes do have advantages, no two stroke oil, quiet (bit like Manos) and hopefully being modern, reliability, therefore there is a real value to using them, but they may not make the big fuel savings you hope for.

It would be interesting to see what a Camel with a 150 Optimax does per hour. Interestingly the best fuel figures I have ever had where when I used a 535 Rib with a single 70 hp two stroke Evinrude. That ran at 4 gph at 36 mph. You will be pushed to do better with a 4 stoke especially given the overall costs.

If you are looking to value a rib, try breaking the components down and see what they would cost individually, then add between 10 and 25% for the package assuming its all in working order.

Regards Pete

Manos · 15 March 2003, 19:09

Quote:

Originally posted by Pete7
.........The 4 strokes do have advantages, no two stroke oil, quiet (bit like Manos).........

ME QUITE!!!

I take this as an insult Sir!! LOLOL

paulford · 15 March 2003, 20:44

Now now gents! Let's tone this down a little shall we? Manos - those colours are, as used to be said in our industry, and particularly of Pimento Red Bentley Turbo 'R's 'a little sudden'!

So what you're really saying is that come what may I'm in for a hefty fuel bill! Sort of expected it really. Not too much of a problem as I'll struggle to get more than 20-30 hours a year or so.

If I end up ordering a new boat am I really better going for twins? I'll be using the boat principally as a dive platform, between 4 and 6 divers and a non-diving coxswain. Will also be used as a fun boat with the family.

Max offshore distance probably 3-4 miles.

Although, as I get braver I might fancy doing a trip between say Anglesey and Dublin.

Pal of mine on an RNLI crew says twins for safety every time. Crosses my mind (and wallet!) that a large single (Yam F115) plus a 10HP donkey engine of some sort would get me out of most situations, except perhaps main engine failure in a heavy sea.

Thoughts members please.

Paul

Manos · 15 March 2003, 21:21

It was a joke

No offence taken and none was intended

Manos · 15 March 2003, 21:32

Quote:

Originally posted by paulford
If I end up ordering a new boat am I really better going for twins? I'll be using the boat principally as a dive platform, between 4 and 6 divers and a non-diving coxswain. Will also be used as a fun boat with the family. Max offshore distance probably 3-4 miles.

I think that twins are better choise however, having said that if you go for twin engines you have double the expense on fuel, servicing etc and double the worry.

I have a 7mtr RIB and use it similarly to what you intend to use yours. I cruise long distances in the summer (over 100 miles at any one time with another 3 of us onboard, which is not that long compare to what others in this forum have done).
I have a 200VMax Yam and an 8bhp Mariner instead of 2x130 Yamahas.
I have used the Mariner once (in force 7 and rugh-..ish sea conditions) to test it and see how it would cope if the main engine broke down. The boat heaved and bumped but it was doing about 7 knots against waves and wind and we were never in any danger.

What I want to say is that your choise of 1 main engine/1 donkey engine is the choise most money consious and sensible people make.

Now probably evrybody will have a go at me LOLOL

jwalker · 15 March 2003, 22:21

Never mind the age, go for condition. A trailer boat, well looked after, (flushed after each outing, properly serviced, kept under cover etc, etc.) will be far better than a boat kept on water.
I agree that you need to look closely at fuel consumption figures. Often 2 stroke is not as bad as is made out. Folk will frequently justify (to themselves) engine purchases which are not really financially sound. If your hours are as low as you think they may be, then, overall, fuel burn is hardly worth considering.
Engines, One big lump + wing engine. Size of wing depends on size/weight of boat. You wouldn't want to be going backwards trying to fight a tide. Twins give you user problems. Balancing the throttles exactly is essential but very tedious. Unbalanced they can give you an almighty beat. If one of a pair of twins stops, the other is then very much over propped and the performance can be dire because the revs wont rise. Or, if they do, the prop has broken loose on the water, which is seriously undesirable.
Twins will give you less performance per HP than the equivalent single. One benefit of twins - if you put fins on the anti-ventilation plates, they give you tremendous lateral stability. One fin on the outer side of each plate works well too.
Hope this is food for thought.
JW.

paulford · 15 March 2003, 22:46

Quote:

Originally posted by jwalker
Twins give you user problems. Balancing the throttles exactly is essential but very tedious. Unbalanced they can give you an almighty beat. If one of a pair of twins stops, the other is then very much over propped and the performance can be dire because the revs wont rise. Or, if they do, the prop has broken loose on the water, which is seriously undesirable.

Understand performance per HP is not as goo on twins - all down to losses in gearboxes and prop performance etc.

Did my RYA Level II on a Cobra with Twin F70 Suzukis and never really had a problem with throttle balance when running both engines.

I don't understand why one engine may be over propped in the event of the other engine failing

? Surely this will be down to how the engines and props are specced from the outset? Advice on this issue from members may save me some serious heartache later.

jwalker · 16 March 2003, 00:59

Er, yes and no.
If the engines were under propped at the outset then this could be the case. But, if correctly propped there will be a problem using just one engine.
Laymans' type of explanation to follow: Imagine you have one 50hp engine driving a boat. If you add another 50hp engine the load on the prop of the first engine will be less because the second engine is helping to push the boat along. If the load on the prop is less, then the engine will find it easier to turn and the engine revs will rise. It would over rev at full throttle. This is, of course, the situation with the second engine too. The solution is to use props of a greater pitch and this also allows a higher top speed to be attained at full throttle.
If this was not the case and, say, the single engine reached max rpm with a 15" prop. The second engine would be the same. How would the boat go faster with twins? Both engines would be turning at the same speed as the single installation and both props have the same pitch. ( Accepting there would be a slight gain because there would be less prop slip.)

OK?

If you had no problems balancing the engines, well and good. As someone who has run twins and tripples for a while, there is a freedom and simplicity in driving a big single. If you get out into waves which are more than a bit bumpy, you'll be working the throttles all the time. You may then change your mind.
JW.

paulford · 16 March 2003, 06:22

Quote:

Originally posted by jwalker If you had no problems balancing the engines, well and good. As someone who has run twins and tripples for a while, there is a freedom and simplicity in driving a big single. If you get out into waves which are more than a bit bumpy, you'll be working the throttles all the time. You may then change your mind.
JW.

I can see that in a heavy sea there'd be more work to keeping the throttles balanced, but ease of so doing must be partly down to the set-up and fine adjustment of the twin engine installation. Whilst I can accept that no two engines will be alike, it can't be beyond the wit of man to get the throttle cables etc. adjusted such that the engines are reasonably balanced with the levers aligned at say 60% -70% throttle opening.

Pete7 · 16 March 2003, 07:59

Paul you are asuming that the throttles stay set once your on the move. Out on the water this just doesn't happen. To drive a rib at any speed you need to read the waves and constantly adjust the throttles, its fine with one, but two is a real pain espcially if they are stiff.

The debate over twins v singles could run on for ever, but for my money it has to be a single if only on the finanical aspects.

If you need to carry six divers with kit then you will need 6m plus to do it in comfort.

Pete

Jonny Fuller · 16 March 2003, 08:17

Ere, JW. It doesn't say on your profile what you do for a living! if that's coz your currently unemployed can I suggest you go into teaching!, that description of single/twin stuff was well cool, very articulate, you have a gift. even manos & CH might have understood that!
P.S. If I'm sounding sycophantic tell me to shut up

jwalker · 16 March 2003, 21:49

Crazyhorse maybe, Manos...Mmmm

Have a look at the joke thread. Yeh, really.
JW.

jwalker · 16 March 2003, 21:55

Paul, as Pete7 said, it's more complicated than that. You'll learn.
JW.

Oh yeh, I meant to mention this before but I had brain fade. You'll get that too if you are out at sea for a while. Then twin throttles will become even more difficult.
If, out on the water, one engine fails, what are you going to do with it? If you leave it down it'll cause almighty drag, If you lift it up you need to steer a motor which will fall from side to side and it will be very heavy. That is, if your steering arrangement will allow you still to steer with one engine lifted. Often it doesn't.

paulford · 17 March 2003, 08:54

I suppose if one lump fails whilst you're out at sea, you may be none too bothered about the drag from it - but more concerned about still having some power to get ashore.

Controlling double throttles in arduous conditions will, I admit, be more challenging than a single. That's all part of the fun isn't it?

Seriously thinking of a new or ex-demo boat now - been to see a few this weekend - some sellers views of condition appear to be at odds with mine - mind you my rose tinted specs are away at the opticians.

So will probably spec out with a Honda 130 or Suzuki 140 four stroke. Honda is a bit of a heavyweight though - nearly 40 kilos heavier than the Suzuki!