Motorbike engine

I remember the CX500 they used a heat exchanger and sea water to cool to closed loop engine water cooling, it worked for a few jet drives without reduction I think, but it didn't catch on although it was a cheap way to get a 50hp jet at the time.
 
Tranona said:
Many attempts in the past using B&S and before that Villiers small aircooled engines for boats. All failed miserably. Noisy, difficult to keep cool, petrol driven, needed large reduction ratios to reduce shaft speed, but few gearboxes suitable.
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I recently sold an old but unused Vincent boat engine, which was a motorbike-derived industrial engine with an integral sterntube and ungeared propeller. It's gone to someone restoring an Amanda water scooter, which used the Vincent and was arguably the first ever PWC ... though with three horsepower on tap it can't have been terribly thrilling. I believe cooling was a bit of an issue with the engine.

Of course Honda still make air-cooled outboards, but I would never, ever trust Honda as they made the carb for our lawnmower obsolete a year after we bought it and about a week before it failed.
 
Sounds a bit like the Atco outboard. Aircooled power head with a fixed drive shaft and prop mounted on a gimball - similar in principle to the Thai motors.

Nobody seems to have followed the Honda example, and from memory think that it is only partly air cooled - just the barrel, and the exhaust is water cooled.

Our old club launches had aircooled Lister 2 cylinder engines with hand starts. Great once you got them going and nice hand warmers when doing rescue boat duties on winter Sunday mornings. The vibrations were good for keeping the blood circulating as well.
 
AngusMcDoon said:
Hot exhaust is a problem as well as engine cooling. There used to be an inboard 'outboard' made which I seem to remember was basically a Honda BF10 mounted in a bed that could be fitted to the hull of a boat like a saildrive. Not seen it for a long time though. Petrol inside was the problem I expect.
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I fitted one of those in our Trapper 300 in 1977, marketed as Volvo, it was a raw water cooled Honda outboard screwed to the top of a VP saildrive leg, certainly not air cooled. We had a lot of problems with exhaust water getting forced back in to the cylinders when it was on a bouncy mooring, the extreme solution was a bung in the exhaust outlet. Volvo Penta lost interest in it after a couple of years though a lot of Ruffian 23s. had fitted them. It was my first VP engine and taught me all I know about Volvo warranties. I do know of 'one' that lasted about 20 years by the owner buying up all the discarded ones and building a spare each winter.
 
How about a Ducati motor?! Surely that would cut a dash through the moorings, with that lovely V-twin throb?

Apparently not. Our boat was originally fitted with an air-cooled Ducati diesel of something like 7hp and presumably single cylinder. The original owner, who fitted out the boat and fitted the engine (early 1980s), said he got the Ducati because it was on some attractive, 'special offer' price, but the first time he started it up he knew it had been a mistake - terribly noisy. Fortunately it was replaced by a modern, water-cooled diesel (Beta) before we bought the boat.
 
Be far more sensible to install an electric motor and drive it from a genny. I wonder if there are any breakers yards with written off hybrids...
Ian
 
ianj99 said:
Be far more sensible to install an electric motor and drive it from a genny. I wonder if there are any breakers yards with written off hybrids...
Ian
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God, how reliable will that be when mixed with a home bodge fit out and salty environment?
 
Quandary said:
I fitted one of those in our Trapper 300 in 1977, marketed as Volvo, it was a raw water cooled Honda outboard screwed to the top of a VP saildrive leg, certainly not air cooled. We had a lot of problems with exhaust water getting forced back in to the cylinders when it was on a bouncy mooring, the extreme solution was a bung in the exhaust outlet. Volvo Penta lost interest in it after a couple of years though a lot of Ruffian 23s. had fitted them. It was my first VP engine and taught me all I know about Volvo warranties. I do know of 'one' that lasted about 20 years by the owner buying up all the discarded ones and building a spare each winter.
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Had one (Volvo MB2 50s 2 cylinder 7.5hp) in my old Pegasus 800, very good engine and ran well.
When I laid up each winter, just used to disconnect the fuel gear and throttle cables, then lift it out and carry it down the ladder on my shoulder to take home. You had to remove the engine from the boat though to change the impellor.

Didn't like having petrol inboard though.
 
TQA said:
Honda Goldwing is w/c and comes with a factory reverse albeit a bodge using the starter motor.
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Precisely why I wrote "bike engines with shaft drive and mechanical reverse". The BMW K1200LT also has a similar reverse 'gear' to the Wing. Not sure why you call it a bodge. It works well enough. More to the point, it works only so long as the button is pressed as opposed to being constantly engaged like a gear. If you've ever tried to ride a bike in reverse, you'd know why this is a good idea.

Oddly enough, about 30 years ago the US federal road safety board, concerned about motorcycle accidents, developed a prototype 'safe' bike. They decided that since a conventional bike's front wheel did lots of important stuff...braking, steering...it should be rear-wheel-steered. It was safe, all right: they never found anyone who could ride it.
 
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Habebty said:
Had one (Volvo MB2 50s 2 cylinder 7.5hp) in my old Pegasus 800, very good engine and ran well.
When I laid up each winter, just used to disconnect the fuel gear and throttle cables, then lift it out and carry it down the ladder on my shoulder to take home. You had to remove the engine from the boat though to change the impellor.
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Here it is...

http://www.cg-marine.dk/page.asp?pageID=75
 
Seem to remember that the Morini v twin from Italy, and much favoured by the Police, has an actual reverse gear.

Of course you can buy a sperate reverse gear mini-box for motorbike powered kit cars, like the Lotus 7 types.
 
rustybarge said:
Seem to remember that the Morini v twin from Italy, and much favoured by the Police, has an actual reverse gear.
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I suspect you're confusing the Morini with Italian tanks, which of course had heaps of reverse gears. The bikes had no such thing. The main unusual thing about them was their Heron heads.

Don't remember them being favoured by Plod, except by some Italian municipal police. Guzzis, on the other hand, even displaced Harleys from CHiPs. But then Harleys were profound rubbish at the time.

Sorry, all. Is this a boating forum...?:rolleyes:
 
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So a big gold wing engine would certainly shift my 26footer against he tide! How many HP and torques does ne of those have?
 
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