full size Dykes piston rings

Having had some very useful advice before and we have members in the full size racing engine scene maybe someone can tell me where to find the following.

I can find model engine and some 250cc twin engine sizes.

I require sizes of full size dykes piston rings around 75mm to 80plus mm and who can I get them from in the UK.

Some of the top dragsters cars use them.

Paul

Edited By Windy on 25/08/2015 15:36:29

TMUK, It seems Google throws up several suppliers in the UK and some suppliers in the USA.

Clive

Oh dear. He's serious about this supersonic steam bike...

I hope Paul's got double-strength bicycle clips.

Neil

There is another ring used on dragsters that I'm considering it utilizes holes in the piston top that use pressure on back of ring to push it on the cylinder might try that on the model.

Not normally used on petrol engines because of carbon that might block the holes.

Just had an invite by a past acquaintance from the bike days to his CNC machine shop to see what he is doing.

After seeing the quality of his work and his involvement with the following to be driven by James Toseland I'm drooling as an amateur machine knob twiddler..

Edited By Windy on 26/08/2015 15:37:51

If he's OK with it, write me a short 'workshop report' for the mag!

Neil

Windy-that looks rather like a record breaker from way past. Built like a space frame, VW flat four moter. It was very advanced for the time, stress gauges etc. The length and positioning of components and rider caculated to reduce tyre spin and front lift. Then he shortened it a lot so that it would fit in the van.

Windy,

Would you know of Graham Sykes [Sykes Engineering] up here in North Yorkshire at Scotch Corner? He is into serious speed racing on two wheels with serious power plant to hurl him down the track. A recent record holder of some kind I vaguely recall.

Nice man and a seriously good workshop where they do really fancy stuff

Brian

Edited By Windy on 26/08/2015 21:00:57

Windy-that's the one, no mention of the technical shortening to fit in the van!. Brings back memories, Alf Hagon, of damper fame and grass track, that was a serious machine- V twin Jap in a speedway frame. No clutch as I remember, just dropped the back wheel on the ground at the right revs.

Dykes rings are a really venerable design.

Modern materials and processes should make them perform even better than when they were first invented.

Before I retired nearly twelve years ago, it had been common practice to have compression rings narrower than the groove depth so that they were gas backed. We found that the ring gap had a big effect on blowby..

The secret was to have a cold fitted gap so small that, when hot (full load rated speed coditions) the ring ends did not butt together. If they did, you were certain to have bore damage and broken rings.

The blowby tended to improve as the engine bedded in, as the rings lapped themselves to the faces of the groove.

Quite a contrast to have a three ring pack that performed much better than the five ring packs of the sixties and seventies, in terms of both blow by and oil control. The better technology , based on experiences, made that possible.

Some "new" things actually ARE better, not just in the minds of the marketing men.

Howard

Paul Dykes was listed as a fellow of college when I matriculated in 1980. However, since he retired from the university engineering department, and as director of studies for engineering in college, in the early 1970s I never got to meet him. I've just re-read his obituary, having dug out the relevant college report. Apparently he started his piston ring research in 1947, sponsored by the motor industry.

Andrew