The Roarer

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It existed in 1935 as a prototype, actually four were built. All have since disappeared. I don't see how calling it a replica is incorrect? I don't know what else you could call it that accurately conveys what Dan has built. It is a machine that is based on all the information that remains from those 1935aircooled AJS SOHC V4 prototypes..

Glen
 
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With another 30 years development, the water cooled 500cc AJS V four might have become a VFR400 ? It was the Japanese and the Germans getting ambitious which stopped the British motorcycle industry reaching it's full potential - nothing to do with lazy unionists or Maggie Thatcher.
 
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worntorn said:
It existed in 1935 as a prototype, actually four were built.
None of those were road bikes though ?

And if you examine it in detail, it is not really like the originals.
It is built as 4 separate top ends, where they were designed and built as an integrated V4.... ?
 
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Who said they were road bikes? Can replicas only be built from road bikes?
In any case they were "fully equipped road going versions, which did not make it into production" So the hang up for you must be production. Dan was particularly interested in replicating this bike because it did not go into production and also because none of the originals remain today. It represented more of a challenge to him than just measuring and copying a currently existing motorcycle. I recall that he spent about a year on drawings, which are quite beautiful. Once he had the drawings complete, the bike was already built in his mind, and a sharp mind it is.

The top end looks identical to the schematic from 1935, in fact that is what the engine is built from.

 "1935, at the Olympia Show, the Bert Collier designed air-cooled sohc AJS 50° V4 was first displayed. It was a fully equipped road going version, which did not make it into production. This first version used a common crankcase with four individual cast iron cylinders and separate alloy heads, with exposed hairpin valve springs, and a 180° crankshaft with forked conrods. There was a central carburettor for each pair of cylinders, and fore and aft exhausts. The single overhead camshafts were chain driven. It had chain primary drive in an oil bath primary chain-case, and a wet clutch. It was stated by AJS at the time that there would be the option of replacing the forward mounted chain driven dynamo with a supercharger. The AJS used a rigid frame with girder forks."
 
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I seem to recall some discussion, somewhere some time back, about the engine layout, cam chains and magneto positions on the 'replica' vis-a-vis on earlier 1930 editions - but of course can't find it......

Looking at Wiki where you got that quote, there was quite a few versions before they came up with watercooling - and something workable. !

Matchless had had the V4 Silver Hawk, a very classy gentlemans tourer, from the 1930 era.
http://www.motosolvang.com/images_new/l ... erhawk.jpg
It too didn't like hot days, or being pushed hard.
But too is highly sought after these days....

Still think the Roarer replica needs its heads turned around, if its going to be seriously used....
 
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Rohan said:
Still think the Roarer replica needs its heads turned around, if its going to be seriously used....
Then it wouldn't be a Roarer. It would be a funny old fashioned motorcycle with its heads on backwards.

cheers
wakeup
 
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Err, as built the heads ARE on backwards !!
One of the reasons they (the aircooled versions) were not a success, in racing anyway.

Gentle road use may be different.
But the Squaffer AND the Silver Hawk - engines also with less than ideal cooling arrangements - had chronic overheating problems in some circumstances, just in road use...
 
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Prior to WW2 fuels such as methanol/benzene were used. Would there really have been a cooling problem ?
 
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The Wiki entry for one of the types of aircooled AJS V4 says it was out within 2 laps of the IoM with overheating problems.

Rear facing exhaust ports don't all have a brilliant record in racing motorcycles.
Especially when they are supercharged.
Not all ideas are good ones....

And so why make an exact copy of something that was a failure.
If folks didn't think they could build a better mousetrap, we'd all still be riding penny farthings...
 
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Looking at the amount of fin area on the Roarer, it is hard to imagine cooling will be a problem.
Can't speak on the prototype aircooled v4s, but the Dan Smith version works very well, no overheating problems there even when flogged hard.

There was mention of the Matchless Silverhawk v4- Dan has an original Matchless Silverhawk which he ended up with because it needed new bevel gears. The previous owner had been unable to locate these after several years of trying and eventually sold the bike to Dan.
Of course Dan whipped up new stuff in no time and had the bike back on the road.
Though nice to look at, It is a very archaic and slow machine to ride. In fact it is such a feat to ride it in modern traffic that Dan presents each new Silverhawk rider with a certificate signed by him and stating that one has "Successfully ridden the Matchless Silverhawk on such and such date..."
By comparison the AJS V4 feels very modern and is extremely smooth, with decent brakes.

Glen
 
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That AJS V4 replica looks to have an all-alloy top end ?
So by not being a totally true-to-type replica, the cooling problems have been solved. ??
Modern metals, oils, fuels and clearances wouldn't hurt either.

Of course, there are owners of Sq4's that say they can't be made to overheat, either....

Matchless had been out of racing for decades when they made the V4 Silver Hawk,
and it was promoted as a 'gentlemans tourer'.
One of THE Classics of all time though...
 
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