Hankering back to boyhood, I was browsing a few sites for the latest in Model Aircraft Engines.

I came upon <A HREF="http://.www.rcvengines">http://.www.rcvengines</A>.

The "RCV" is for Rotary Cylinder Valve.
The cylinder comprises a rotary inner sleeve, geared to rotate at half crankshaft speed and containing the porting in the head. As the sleeve rotates, it uncovers the inlet port, on compression it uncovers the plug (glow plug in this case) then the ehaustt port. The engine operates on the four stroke cycle.
One design is of the conventional vertical cylinder configuration. There is an unusual design whereby the actual propeller drive is taken from the end of the horizontal rotating inner cylinder. This enables larger props to be driven at half engine speed, ideal for vintage scale models.
I was taken back to the days of the Barr and Stroud Sleeve Valve engine with a combination of the Cross and Aspin rotary valves.
I understand that the RCV Engine company has ventured into small motor cycle engines.
Now, with the benefit of modern materials and precision CNC machining, the old ideas are coming back as a reality.

i could never understand why the norton rotary engine disappeared up its own chuff, in a racing sense of course. all that power from that tiny little engine. these rotaries must be reliable enough now - mazda still make and market their rx range of sports cars, all use rotary engines.
ade!

I have never heard much mention of it but in the 1950s.Norton developed a Manx engine which eliminated the use of poppet valves by replacing with and inlet and exhaust rotating cylindrical sleeve.I believe sealing problems caused it to be abandoned.It would be interesting to know if the engine is still in existance.

Here's a link to some really interesting reading regarding engine development over the years.

Click Here

Does anyone remember Dr Joe Erlich and his ideas for different engine development ?

He was the one who brought the Rotax engine into the motorcycling world some 20+ years ago, with Chris Grose (a Manxie) being one of the development riders way back in the early 80's. ( A Link to Chris's experiences are below)

Didn't Con Law ride a bike with a derivitive of his engine in TT in the early 80's ?

I remember a few years ago, some kind of agreement with Brabham (I think), for a variable capacity engine that he was working on. Can't remember exactly how it worked, but with the flick of a lever, the engine capacity could be altered from 250cc to 300cc, or was it even higher ??

A brilliant mind and such a genius, that sadly is no longer with us.

Click Here

Arthur, the Norton engine's rotary ("Revolutionary") valve was the the Cross Valve.
The biggest problem at the time was the severe temperature gradient between inlet and ehaust ports on the rotary portion. It was wery difficult the ensure proper lubrication and sealing.
With modern technology and materials, I believe that Ceramics could be used to combat the temperature and expansion/sealing difficulties.
Currently, with any sort of rotary valve the nature of the relatively high speed rubbing syndrome tends to consume the lubricants and this leads to wear and unfriendly emmission problems.
The same applies to the Aspin rotary valve featured in Malcolm's link.
When you think of the high temperatures attainable with domestic non-stick frying pans and the modern use Nikasil cylinder bores, I still believe that there is a lot of scope for investment and development of the rotary valve AND the Wankle Potary Engine.

Perhaps you are refering to the e3 engine Ehrlich designed and with Jack's help introduced to the Mayflower company.

<A HREF="http://news.bbc.co.uk/1/hi/sci/tech/1573288.stm">http://news.bbc.co.uk/1/hi/sci/tech/1573288.stm</A>

Brabham is a great promoter of new technology, being an engineer himself.

He is also involved with the 6 stroke Beare cylinder head is explained on his website and is applicable to motorcycles.

It might give the authorities a bit of a Head ache though.

<A HREF="http://www.jack-brabham-engines.com/">http://www.jack-brabham-engines.com/</A>

I would love to have heard that Barr & Stroud sleeve valve twin in the Brough.

I know that Joe developed the "Split Single" two-stroke configuration as in the famous EMC. Does anyone know if he also did any work on the "Des Axe'" principal, whereby the cylinder centre line was offset forward (on normal forward rotating engines) to provide the power thrust forward of the crankshaft centre line. It seems that Mayflower have achieved this by other means. The offset cylinder axis for 2-stroke applications had a further beneficial effect in providing assymetric port timing, as did Joe's Split Singles.

It will require more research but I think Honda have been using the double axis approach for a while now.
On their Insight hybrid car the engine is only a small lightweight 3 cylinder, with a 14mm difference between the crank and cylinder axis
It is said to reduce side thrust just after TDC and thus reduce internal friction.
Someone said there seems to be an increase of bearing load at BDC due to increased acceleration at this point but improved materials
have possibly overcome this.