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Identify these bikes! / Re: Barr and Stroud mystery bike
« Last post by 33d6 on April 13, 2018, 08:35:03 AM »
Having explored the innards of one of JFergs B&S engines in company with him I can't really see how one could say they were difficult to get the port timing right but I'd certainly agree that just because you know how a cam operates to push open an inlet or exhaust valve doesn't mean you totally and fully understand the sleeve valve at first glance. It does require some degree of thought and some people find thinking very tricky.
I also think you can't really compare a double sleeve valve engine like the Knight to a single sleeve valve engine like the B&S. In one move the single sleeve valve reduces engine complexity by half thus markedly reducing any tendency for the famed sleeve valve smoking and excessive oil use. You have to remember the great majority if not all smoking sleeve valve stories all relate to double sleeve valve engines.  B&S motorcycle engines have exactly the same total loss oiling system as every other motorcycle engine of their day and use no more nor no less oil than any other and smoke no more nor no less than any other.

And yes, R, two stroke oil is very good in sleeve valves as JFerg will confirm. His is well pleased with it.

It's a pity the sleeve valve engine didn't receive a fraction of the effort and development as the 'umble poppet valve but it didn't and we now have a fascinating side story of what could have happened but didn't. It keeps us entertained doesn't it.
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Identify these bikes! / Re: Barr and Stroud mystery bike
« Last post by JFerg on April 13, 2018, 08:21:34 AM »
There are sleeve valves and sleeve valves.

Knight and Minerva used two sleeves reciprocating with the piston in the middle.  The ports are small, like letterbox slots, and the wear is concentrated. 

B&S, Bristol, Napier and RR used single sleeves where the action is an elliptical path, with large ports, rapid openings, and good spread of lubricant which also spread the wear over a very large area.   The single sleeve aero engines were the most powerful spark ignition engines ever built, rendered obsolete by jet turbines.  Where poppet vale aero engines generally had a 500 hour service life, the single sleeve valve engines had a 1500 hour interval.  If single sleeve valves had anywhere near the gazillions of engineer-hours applied to them that poppet valves have had, there's be a lot more about.

I owe you an apology, Leon.  I've been severely tangled in life and other issues of late, and not had the chance to properly study the extracts you sent me.  I will get there, come May I will have shed a major workload.

Thank you for your Herald research.  As 33d6 suspects, I can postulate the engine number of this machine.  Norm Maplestone bought two B&S V twins.  He also reputedly had a shop in Kew, next to Mont Albert.  Tantalising.

That Czech bike is probably a "Kopra", too.

JFerg
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Identify these bikes! / Re: Barr and Stroud mystery bike
« Last post by R on April 13, 2018, 03:54:36 AM »
Not much B&S content here, but we've followed along behind a little Daimler Knight on a veterans rally, and it ran along very nicely and smokelessly. Chatting about it afterwards, he said he'd modified it, I think with something somehow related to a Suzuki (port timings ?) and used (smokeless) modern 2 stroke oil. We waz imprezzed !

No need to remind folks that there was some very big and powerful sleeve valve aero engines to come out of WW2. Its amazing how little mechanical noise there is with no valve gear thrashing about - which operationally gave some of them a considerable advantage.
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Identify these bikes! / Re: Barr and Stroud mystery bike
« Last post by john.k on April 13, 2018, 02:39:05 AM »
Ive heard said that B&S motors were very difficult to get the port timing right,and often refused to run after repair...years ago I had a Willys Knight 66 of 1930 vintage,because it had but one timing shaft,things were easy-ish.I "found" the car because I worked at Repco,and the owner had sent the motor in from the bush for overhaul,and was quoted a massive sum.......a year later the motor was still sitting in the shop,and so I found the owner and bought the car......I managed to get the reco done in stages for free....some was pretty out of the ordinary,the steel sleeves had to be flame sprayed with babbit,and ground to size....In those days Repco regularly remetalled vintage car (and diesel) big ends.....After the reco,the motor ran real well and was completely silent,but used bulk oil....like 5 gallons in a 200 mile rally.....It took a lot of miles for the motor to settle down.....I had been warned about this by the old timers at Repco.
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Identify these bikes! / Re: Barr and Stroud mystery bike
« Last post by cardan on April 13, 2018, 12:12:41 AM »

What a pity that thought didn't stand up to scrutiny - it would have been a classic story.

On the sleeve-valve-motors-in-Melbourne theme: If a Barr and Stroud and Minerva - with full length sleeves controlling the ports - was called a sleeve valve, what was the Peugeot effort - with  very short sleeve - called?

"Cuff valve"! The late Jack Nelson owned one, as a young man in Melbourne just after the war. Nice car.

Cheers

Leon
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Thank you
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Identify these bikes! / Re: Barr and Stroud mystery bike
« Last post by 33d6 on April 12, 2018, 10:39:38 AM »
The original 7 Zetland Rd house is long gone unfortunately. For a moment I was hoping it could be our house as Iíve been told our garage housed a Minerva during WWll and as a boy a local VVMCC member remembered the owner carefully cranking it over to keep the sleeves free. It wasnít much of a leap to hope he was the local sleeve valve nut and he started out building his own cycle car. No such luck though.
I have found out the Davies were the local estate agents. Iíll keep digging.
Cheers,
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Identify these bikes! / Re: Barr and Stroud mystery bike
« Last post by cardan on April 12, 2018, 01:32:36 AM »

Davies lived at 7 Zetland Road, Mont Albert. Maybe you can see if he's home? If not, check the crumbling shed at the bottom of the garden...
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British Bikes / Re: V2 Matchless
« Last post by john.k on April 12, 2018, 01:20:27 AM »
He definitely specified cam followers.......
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Identify these bikes! / Re: Barr and Stroud mystery bike
« Last post by cardan on April 12, 2018, 01:15:52 AM »

Hi 33d6,

Oh it's a cute thing! I do like a good cycle car.

JFerg and I recently discovered that quite a number of "Coventry B&S" motorcycles came in to Western Australia, complete with B&S engines, so in Australia we had both B&S bikes and loose engines.

I have method in my file names: yyyy-mm-dd-papername, so in this case 1928-08-20-herald-melbourne.jpg translates to the Herald, 20 August 1928. I don't usually use page numbers - I've found in the past that the Adelaide newspapers had several editions per day, and sometimes articles were moved.

Getting better photos is tough. In this case the Trove scan is pretty good, and a scan from the original newspaper wouldn't be too much better. At the State Library of South Australia, processing for Trove involved separating pages, and the papers were then properly packaged and put into "deep storage". I think I paid $60 to get a paper out last time I wanted a photo, but in that case the Trove scan was total rubbish. The staff at the library were amazed that I had been able to convince the powers that be to get the relevant paper out at all, and it was only because I convinced them that I was doing serious research, and the Trove scan was not fit for purpose.

Since the Herald is still around, I wonder if they still have an archive of photos that goes back to 1928? Now that would be interesting.

Cheers

Leon
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