What's going to happen ? (Shaft v Outdrives)

Re: What\'s going to happen ? (Shaft v Outdrives)

What you have to factor in is................

It is the efficiency of the drive unit that makes the savings over shafts not the engines eg...........for shaft drive boats to get the same peformance of say a mid 40' sports cruiser on outdrives you need around 500hp per lump as oppossed to around twin 350hp on drives. I am no maths guru but twin 350's on drives burn around 75 litres an hour (both), twin 500's on shafts around 110 litres an hour (both) so if fuel tax goes on that is a whooping extra cost just to have shafts. Factor in also that drives are way cheaper to install than shafts... and because of lower labour cost to install and smaller engines you can talk about £40 - £50K difference in the retail price of 42' sports cruiser..... that buys you an awful lot of servicing over the years. As far as reliability is concerned the latest units from all the manufacturers are yonks ahead of those from even 10 years ago.

Add of course (for sports orientated boats anyway) drives are loads more fun to drive with much more responsive steering, all in all much more chuckable.

IPS is the way things are heading for bigger boats, nearly all the med yards have new boats on the drawing board for IPS, us Brits are way behind the race on this one. Nearly every major yard around the med will be launching new boats next season with IPS. Some are dropping or not even designing in the ability for shaft drive installation.

The savings as you start to move up the power range and size of boat fitted with IPS really do start to make shafts look very expensive to run indeed, at around 55' the fuel burn for IPS600 will be around 60% of similar shaft drive installation. When you are looking at burning 160 litres an hour that is bags fulls of cash.

You pays your money and takes your choice as they say but shafts won't be getting any of mine, its too blooming hard to earn without throwing it away as well.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

As stated above,outdrives may be more efficient on fast boats being used at high speeds,but at displacement and slow speeds suspect very little advantage at all to outweigh the delightful ability of those pesky legs to devour money and keep you glancing over the stern to find out exactly what that new funny noise/oil slick etc is coming from. /forums/images/graemlins/confused.gif
 
Re: What\'s going to happen ? (Shaft v Outdrives)

I didn't realise there were other countries that had to beg the EU for an extension, derogation, whatever they call it.

I still think if Gordon Brown has anything to do with it we are doomed. I'm sure he will only look at the potential loss of votes and decide rightly or wrongly that we are all rich tory arseholes who deserve whatever we get.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

I agree about the improved reliability. Maybe I've been very lucky but I've had no problems with my single outdrive. Having said that it doesn't have many hours.

But the engineering & reliability must be improving significantly. There is huge competition out there both to perform and be reliable.

In general I think significant hikes in diesel price can't help but make a difference to peoples choices.

If it goes up to 5quid / gallon I may get a row boat ! It's not just the money it's the principle. Either that or move new boat out of the UK !!
 
Re: What\'s going to happen ? (Shaft v Outdrives)

An increase in diesel costs won't make a jot of difference.

No serious boater would choose outdrives over straight shafts given a straight choice. It's not just the maintenance costs etc, a (twin) shaft drive boat is easier to handle, it is a more seamanlike robust simpler system, the boat will be better in a sea (due to weight of engine further forward) etc.

And the non serious boaters don't use their boat enough for it to matter.

But more than that, there are very few boats where you actually have a choice. Even the V42 which used to be available with V-drives or outdrives is now only available with outdrives I believe (cos so few people were willing to pay about £20,000 more for a boat that didn't go any faster). So ultimately the drive system will come down to choice of boat. Buy a sub 40ft sportscruiser or something like a Sealine F33 and you'll have outdrives. Buy a proper flybridge boat and you'll be on shafts. And I doubt people will go out and buy a boat they didn't want just to get a small fuel saving.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

Er, disagree on that one my friend, don't think many Botnia Targa owners would be pleased to hear you call their boats unseaman like nor would plod or Customs & Excise operators.

Have driven many a shaft drive boat that was a pig in weather and some outdrives that are a delight and vise versa. A well designed and put together outdrive boat is just as good and in some cases better than a shaft drive in bad weather, for a start it is more more responsive to the helm which is a real boon when driving down the weather, you also have loads of trim to play with which you don't on shafts.

Agree that shafts are easier to handle close quarters but if you have never driven anything but outdrives does'nt really factor into it you just learn how to do it. The big diference in handling is when you start to get moving, drives just run rings round shafts.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

Eh??? Drive efficiency is drive efficiency, why would "big waves" make a difference,if you are talking about extreme weather then that is hardly an argument against for the other 99% of the time (100% in most boats) - surely /forums/images/graemlins/confused.gif
 
Re: What\'s going to happen ? (Shaft v Outdrives)

Only trouble with outdrives, they are made of corrosion prone aluminuim have, to many seals, shafts, bearings, gears, dog clutches and universal joints. IMHO
 
Re: What\'s going to happen ? (Shaft v Outdrives)

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Have driven many a shaft drive boat that was a pig in weather and some outdrives that are a delight and vise versa. A well designed and put together outdrive boat is just as good and in some cases better than a shaft drive in bad weather,

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If an outdrive boat has a better hull than a particular shaft drive boat then like for like of course it will be better. But given the choice of configuration in an identical hull the shaft drive boat will be superior every time. Just one example, years ago they offered the Fairline Corniche with either conventional shafts or outdrives. The conventional shaft boat was far superior, as proven by it's higher resale value and greater desirability (assuming all else equal) despite being cheaper than the outdrive version when new.

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Agree that shafts are easier to handle close quarters but if you have never driven anything but outdrives does'nt really factor into it you just learn how to do it.

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And you've clearly never close quarters maneuvered a Fairline Targa 39 with no bow thruster in a brisk crosswind!! /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
 
Re: What\'s going to happen ? (Shaft v Outdrives)

I read recently about new Volvo plastic outdrives. They are in production I believe but very new & so far only in the USA.
In fact I've just found the article in MBM. They say "Could this be the beginning of the end for outdrive leg corrosion" ?
 
Re: What\'s going to happen ? (Shaft v Outdrives)

You'll still have the added complication of the fact it steers, tilts etc though, with all the associated hydraulics, rubber bellows etc.

I'm not anti outdrive by the way, in a small sportsboat they are the only real choice, just think (to answer the original question) that changes in fuel tax will not affect values of shaft drive boats cos they are different animals with their own plus points, and anyway there is very little crossover (ie boats offered with either option).
 
Re: What\'s going to happen ? (Shaft v Outdrives)

I agree there is not often the option of shafts or drives on a given boat but one could chose a similar boat.

By the way I don't want to disagree with you. I want to switch to a shaft boat myself but remain unconvinced that tripling diesel cost will have little impact say a couple of years down the road.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

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I want to switch to a shaft boat myself

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You've hit the nail on the head right there. Which the exception of sportsboats, where performance and "sporty" handling is the number one priority, most people would prefer shaft drive just like you. Back to the Corniche example of earlier, the shaft drive versions command a noticably higher value because it's what people want.

Boating is an expensive sport. I can't see many people compromising their number one choice just to save a couple of hundred quid.

And as I said earlier, in mosty cases you choose your boat, and then have no option as to drive configuration. Not many people wanting (say) a flybridge 40 footer are going to opt for a sports style instead just because it's on outdrives and that will save them a few quid. People don't buy 40 foot boats if they're on that much of a budget.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

I want the bigger boat so I can go further, with family. It just happens that the boat I prefer is a shaft drive only.
Trouble is if I go further (over the channel) the 'few quid' could turn into a few hundred quid.
And as I said earlier it's not just a matter of being able to afford the extra cost, which I can easily, it's the principle of coughing up extra money, ie tax. It may just spoil the pleasure bit.
Maybe I should just pay up and take pleasure in knowing that with every Nm I do I'm helping the treasury help people far less fortunate than myself. /forums/images/graemlins/mad.gif
 
Re: What\'s going to happen ? (Shaft v Outdrives)

The "shaft being superior to outdrive" debate has and will rage for years. However, I think that those of you who damn the outdrive package out of hand should remember, that without them, the many sportsboats up to around 40/42' would have very poor interior accomodation indeed. The only way to get anything like reasonable interior layout on these boats is to have the engines at the stern, and therefore, outdrives. Before you all shout, I know there are V drives which would also answer the outdrive "problem", but few are offered, and are by reputation are pretty inneffecient due to the drive being turned through 180 degrees.

I have had 6 different boats fitted with outdrives (all but one of them being Sealines), and have been perhaps lucky, but they have all been totally reliable. I've also had friends who have had problems with them, but in fairness, this has been usually brought about by netting/old lines being discarded by our fishermen friends (as happened to me recently - luckily, such damage is usually covered by insurance). This is also a situation where contra-rotating duo prop outdrives are at a disadvantage over single prop variants, which seem to be less affected. In both cases, the outdrives can be lifted whilst the boat is in the water, and the debris cleared without having to dive under the boat (not for the faint hearted!) In my view, with more and more rubbish appearing in our waters, this is a BIG plus.

On the other hand, I also know of two Brooms, one a 42 that sank at it's mooring, and another 52 that VERY nearly did (only a luckily timed visit by it's owner, and very quick action by the marina staff at 10.30 at night saved the day) due to shaft seals failing. All in all, I still cannot see that a tripling of diesel price will affect the prices of shaft driven boats. There are those that will have outdrives, and those that won't, those that want sportsboats, and those that prefer flybridges (few of which above 34' are offered with anything other that shafts.

One final point, I personally find that the ability to vector the thrust on an outdrive boat, albeit coupled with a bowthruster, gives tremendous control in windy conditions, though of course without the aid of a bow prop, their more inboard postiioning than shafts will render them more difficult than the latter in a blow.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

Not so sure,

There is no such thing as a multi fit hull, it is either designed for shafts or designed for drives, once you try crossing from one to the other in the same hull it rarely works as per your case in point for the Fairline. You put shafts into a Botina Targa and it will only be half the boat it was on drives.

The argument that shafts will always be the better system in heavy weather does'nt hold water, the boat as a package will either be good or bad, drive system is only a part factor. I would rather be out in a houlie in say a Nord West 390 on drives than many makes on shafts.

Hull design is a very complicated process as some yards have discovered with IPS, it is not a case of just dropping in a new drive system and hey presto its all going to be tickety boo.

Nearly all the big ribs up to 12 metres, are all mostly outdrive boats or jets and they go through some of the most horrible weather you can chuck at them.

If you are having trouble driving twin outdrives then just drive it like a single and try not to use the engines to swing the boat, again, bit if practice and you can put it anywhere in any conditions just about but it does take practice.

Nowadays we want it all push button and are in danger of loosing some of our skills, I often switch off the bow prop just to have a go on the engines alongside, first time usually cock it up but after another few goes it comes back to me and very rewarding it is too when you get it bob on.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

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I want the bigger boat so I can go further, with family. It just happens that the boat I prefer is a shaft drive only.

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Exactly. So it's down to choice of boat not choice of drive system, which is why change in diesel price will have no effect as there is (in 99% of cases) no alternatives.


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Trouble is if I go further (over the channel) the 'few quid' could turn into a few hundred quid.

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I can't see the difference between shaft and outdrive amounting to "a few hundred quid". You can only get diesel outdrives up to 350hp and therefore about 40ft ish. They just don't use enough fuel to amount to hundreds of pounds worth of difference. I reckon on your typical 35 footer outdrives wouild save you a gallon or two an hour at best, thats £5-10 an hour difference. If it's that critical better buy a yacht! /forums/images/graemlins/grin.gif

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And as I said earlier it's not just a matter of being able to afford the extra cost, which I can easily, it's the principle of coughing up extra money, ie tax. It may just spoil the pleasure bit.
Maybe I should just pay up and take pleasure in knowing that with every Nm I do I'm helping the treasury help people far less fortunate than myself. /forums/images/graemlins/mad.gif

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Or buy a yacht or buy a slightly smaller boat or go slightly slower, no ones forcing you across! /forums/images/graemlins/grin.gif
 
Re: What\'s going to happen ? (Shaft v Outdrives)

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The "shaft being superior to outdrive" debate has and will rage for years. However, I think that those of you who damn the outdrive package out of hand should remember, that without them, the many sportsboats up to around 40/42' would have very poor interior accomodation indeed. The only way to get anything like reasonable interior layout on these boats is to have the engines at the stern, and therefore, outdrives. Before you all shout, I know there are V drives which would also answer the outdrive "problem", but few are offered, and are by reputation are pretty inneffecient due to the drive being turned through 180 degrees.


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I couldn't agree more. Thats why the circa 1990 Princess 36 Riviera (which was nearly 40ft) had no more cabin space than the Targa 33.

What the Princess was however was a vastly better sea boat due to that shaft drive configuration.

But no one buys boats at boatshows based on seakeeping, they all want acres of space, hence (as you rightly say) manufacturers opting for the huge packaging advantages of outdrives for sportscruisers.

The other advantage to outdrives for manufacturers of course is way simpler and easier installation. Just cut a big hole in the back and screw the engine to one side and the outdrive to the other. Much easier than sourcing props, P brackets etc and having to align and balance it all up.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

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The argument that shafts will always be the better system in heavy weather does'nt hold water, the boat as a package will either be good or bad, drive system is only a part factor. I would rather be out in a houlie in say a Nord West 390 on drives than many makes on shafts.

Hull design is a very complicated process as some yards have discovered with IPS, it is not a case of just dropping in a new drive system and hey presto its all going to be tickety boo.


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Don't see many serious offshore lifeboats or pilot boats on outdrives though do you? Or Nelsons or Weymouths etc etc.

Botina Targas use them for better packaging and better performance (which suits users like the police), not the ultimate in seakeeping.

RIBs use them for the same reasons.
 
Re: What\'s going to happen ? (Shaft v Outdrives)

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Before you all shout, I know there are V drives which would also answer the outdrive "problem", but few are offered, and are by reputation are pretty inneffecient due to the drive being turned through 180 degrees.


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Agreed that there will be an efficiency loss due to having the V drive gearbox in the power train but IMHO this will be very small. Why do you say 'pretty inefficient'?

Also its not true to say that few are offered. Some Italian builders have used them for years and so have Sunseeker on some of their flybridge models. Sealine use them on their new T50. It could be that some builders are finally waking up to the packaging advantages that V drives offer although when larger IPS systems come on stream, V drives could disappear
 
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