[cyrusb]

Ran into this on you tube. Very interesting. Watch the red marks, they stay motionless until the speeds get high. So it appears if you want to spin your valves, give it a good rev.  http://youtu.be/nsa6kq-qqIE

[SRL790]

Interesting, but I don't think my Enfield is going to reach 14,000 rpm.

Andy

[GreenMachine]

It was a good vid...I betcha my enfield could hold together  at 14k rpm  ...

[Bullet Whisperer]

When I worked as an engineer on the tugs, one vessel had a 3000 bhp 8 cyl Deutz engine, with enormous valves about 3 ft long and 6 inch diameter. These were fitted in their own sub assemblies, or 'cages', which could be removed without disturbing the massive cylinder heads. The bottom spring seats were a kind of large sandwich bearing, with a circle of ball bearings in a track which allowed the valves to rotate freely. This engine ran at about 400 rpm flat out from memory and you could watch the valves rotating from the top walkway around the engine as it ran. They all did their own thing, some spinning slowly one way, while others went the other way and some rotating back and forth. It helped keep the seatings and any wear even.
 That said, an old AEC diesel driving a generator on another vessel had 'Masked' inlet valves, a crescent shaped ridge about half way round the back of the valve head directing the incoming air around the valve stem and guide. These valves had a flat running up one side of the stem and a 'keeper' incorporated in the lower spring cup to prevent rotation of the valves. That engine racked up many thousands of hours without any trouble.
 B.W.

[The Garbone]

After working on my Enfields and reading your post I have determined I would have been happy working as a marine diesel mechanic.  Very cool.

[Bullet Whisperer]

After working on my Enfields and reading your post I have determined I would have been happy working as a marine diesel mechanic.  Very cool.

Thanks! My 'Swansong' was the rebuild of a V16 B&W Alpha 16V23L, which had run away at over 2,000 rpm [max speed 830 rpm usually], after someone messed with the governor. This 16 ton engine was one of a pair and had to be lifted by four large chain blocks and tipped through 90 degrees to remove the crankshaft, then a hole cut in the deck gave access to get it out and the new one in. This weighed 1.5 tons and cost £80,000 ! Damaged pistons, conrods and valves were changed and it took about four guys nearly two weeks to grind the 32 valves in alone !
 It was a big moment for me when we fired the rebuilt engine up - there were some people working in that company that must have been itching to see it go wrong, but apart from one slight blow on one head joint to sort, it was all ok. I remained as chief engineer on this vessel [Valiant Nader, 5,000 bhp] until the engine was run in and passed as fit for service and my neighsayers silenced, then turned my back on it all to work on classic bikes, which I still do today. I saw and worked with some very interesting machinery over ten or so years, though.
 B.W.

[Arizoni]

There are several different kinds of valve rotator systems that have been around for years.

One system allows the valve to be free of the valve spring retainer when the retainer and spring is compressed.  This allows the valve to rotate by forces induced into the valve by engine vibration.

Another system uses balls or rollers to support a lower end valve spring retainer and sometimes has another set of spring loaded balls in the upper valve spring retainer.
When compressed the upper retainer rotates the valve and the valve spring slightly.

Of course there are others like the one in the video.
I think that one may have been unintended although I don't know for sure.
It appears that at certain frequencies there is a brief moment where both ends of the spring may be unloaded as the springs starts to 'float'.  During this short time, engine vibration causes them to rotate one direction or the other depending on the frequency.

Then there's Royal Enfield who felt that in moving both axially and rotationally the valves might be confused and loose their sense of direction so they just stuck with the axial movement, this being the most important of the two.
Nothing beats old time engineering, I say. 

[Chasfield]

Thanks! My 'Swansong' was the rebuild of a V16 B&W Alpha 16V23L, which had run away at over 2,000 rpm [max speed 830 rpm usually], after someone messed with the governor. This 16 ton engine was one of a pair and had to be lifted by four large chain blocks and tipped through 90 degrees to remove the crankshaft, then a hole cut in the deck gave access to get it out and the new one in. This weighed 1.5 tons and cost £80,000 ! Damaged pistons, conrods and valves were changed and it took about four guys nearly two weeks to grind the 32 valves in alone !
 It was a big moment for me when we fired the rebuilt engine up - there were some people working in that company that must have been itching to see it go wrong, but apart from one slight blow on one head joint to sort, it was all ok. I remained as chief engineer on this vessel [Valiant Nader, 5,000 bhp] until the engine was run in and passed as fit for service and my neighsayers silenced, then turned my back on it all to work on classic bikes, which I still do today. I saw and worked with some very interesting machinery over ten or so years, though.
 B.W.

I hear those Boss Hoss folk are going to put one of those motors in their next bike. Watch out for plenty'o Youtube vids, of righteous bros showing there machine start up and idle/melt its 30ft back tyre.

 

[SRL790]

My first trip to sea was on a ship powered by a Sulzer 6RND90.  This was an inline six cylinder diesel with a 90 cm bore and ran 110 rpm flat out.  When we needed to remove the ridge left in the top of a cylinder instead of using a bore hone you just jumped inside with an angle grinder!  The crankshaft was direct coupled to the prop shaft and if you needed to go astern an elctric motor retimed the camshaft and you started the engine in reverse.

I now work in a gas tubine power generation plant.  We have two GE gas turbines rated at 220,000 hp each.  A turbine rotor (with 18 rows of compressor blades and three rows of turbine blades) weighs almost 50 tons.  Add on another 40 tons for the generator rotor thats one helluva lot of rotatating mass.

Don't think you could fit one in a motorcycle frame.

Andy

[Lwt Big Cheese]

Sounds like a challange!

[cyrusb]

Interesting, but I don't think my Enfield is going to reach 14,000 rpm.

Andy

Well, yes, but the cam is only doing 7,000.