ESE's works engine tuner

[husaberg]

Ryger are using a standard bottom end so you will see the original transfers in the case. The plate seals all this off as there would be a large valve guide type thing in the middle that the crank is connected to, bottom end is now fourstroke type, plain bearing pressure fed bigend. So all the twostroke stuff goes on above the plate (and in the plate). Easy to imagine 11 transfers, could be one ring of ports on top of another? Because they are using reeds in the transfers and up close to the cylinder ( I think ) there is no need for a conventional reed in the induction as we are used to, this is a red herring. As wobbly points out, there is no reed block sandwiched in there. I don't know, just my observation.

Rod is 20mm shorter and the spacer is approx 25mm taller, add to that a shorter piston, everything seems to "stack" up.

I am with you Neil the cylinder is custom made Ryger. Yet they needed to keep the plate separate from the new cylinder for a reason.

[Grumph]

I am with you Neil the cylinder is custom made Ryger. Yet they needed to keep the plate separate from the new cylinder for a reason.

If - and at this stage it's still a BIG if - there is a guided rod, it still has to be assembled...Given some kind of "normal" small end sizing there's going to have to be some kind of built up bearing/seal assembly on the plate. Also cylinder manufacture is at least easier without a blind end...
Many reasons possible for the separate plate IMO.

[husaberg]

If - and at this stage it's still a BIG if - there is a guided rod, it still has to be assembled...Given some kind of "normal" small end sizing there's going to have to be some kind of built up bearing/seal assembly on the plate. Also cylinder manufacture is at least easier without a blind end...
Many reasons possible for the separate plate IMO.

Likely many, but how do they work when the rod is at least 20mm shorter than standard, yet the cylinder is at least 20mm taller with the added plate.

[Flettner]

Likely many, but how do they work when the rod is at least 20mm shorter than standard, yet the cylinder is at least 20mm taller with the added plate.

Luckily just the right numbers to fit it all in ( plate 25mm by the way )

[RAW]

Luckily just the right numbers to fit it all in ( plate 25mm by the way )

Can't find it at the moment but I'm sure the plate in question is 35mm thick. Anyone have confirmation of this ?

[husaberg]

Luckily just the right numbers to fit it all in ( plate 25mm by the way )

Can't find it at the moment but I'm sure the plate in question is 35mm thick. Anyone have confirmation of this ?

The plot thickens, have to get Ken in to stir it

[emess]

[QUOTE=Flettner;1130890182] Because they are using reeds in the transfers and up close to the cylinder ( I think ) there is no need for a conventional reed in the induction as we are used to, this is a red herring. As wobbly points out, there is no reed block sandwiched in there. I don't know, just my observation.
/QUOTE]

Mmmm then why go to the trouble of making a reed shaped housing ?

(the suspense generated here is better than a load of Hollywood movies)

Mick

[RAW]

Is this the suspect spacer

[ken seeber]

From the pics originally posted by Frits, I had initially estimated the spacer length to be around 25 mm.

Well today, prompted by that Husa, after scaling the VM homologation drawings, remembering that the Ryger cylinder is closely based on this (one can see this when putting the 2 pics side by side, the cylinder length is around 103 mm, from the top deck to the crankcase face. I say around as there is some slight perspective distortion. So, with the latest pics, using this 103 length, the spacer length scales at 20.1 mm. So, to me, I would say a nominal 20 mm, give or take a bee’s dick. In fact, if you look at the spacer and right next to is an M6 cap screw. The head of the cap screw is basically 50% of the thickness of the spacer. Knowing that a M6 screw's head is 10 mm, this supports the 20 mm estimation.

Taking this a bit further. Assuming the piston edge at TDC reaches the same point relative to the barrel and the rod is 20 mm shorter (than a VM) and the compression height of a piston of a generic KZ engine is 29 mm, then the compression height of a possible piston would be 29 + 20 + 20 = 69. Much longer and heavier.

Now, assuming the piston is conventional, in this case Ø54 mm along its full length, and the crankcase is sealed off, then the piston might have an oil scraper ring at the bottom of the skirt. The homologation application doccos indicate 2 rings. One wouldn’t want the oil scraper to uncover the ports at TDC, thereby allowing some communication of oil from the wet sump crankcase into the fresh mixture passages. So, the top of the oil scraper would be around 54 +2 or so, = 56 mm down from the top edge. Given a 2 mm scraper and another 2 mm of material below the ring, then the skirt length would be at least 60 mm. However, if the pin was 69 mm down, this would imply that the piston would need to be much longer to support the pin boss. It would also need to be a full skirt piston. Weight ? 30K?

However, all this could be crap as we don’t really know what is going on, and the above would assume that, as the crankcase delta V was not contributing to drawing any intake charge, there must be some other snazzy method of drawing in the mixture, seemingly way beyond the capacity of a tuned pipe.

Dunno about your spacer pic Rick, it looks too thick to me, but who knows.

Fletto and Husa have suggested all sorts of stepped pistons and they may be right.

Hollywood? haven't seen any women so far in the script, but Wobbly did make mention of Paris.

[AndreasL]

Is this the suspect spacer

The clamp in the background looks very small...or the "spacer" is really big if you ask me.

So I say no, not a Ryger.

[speedpro]

Spacer appears to be for a horizontally mounted cylinder - note the oil feed holes up the side of the transfer passage

[TerraRoot]

we must go back, but not as far back as some of the other guys have here, only to the 70's.. it's piston ported!

but seriously, well happy for ryger, really though this would be buried under and lost in patent rubbish for years. Can't wait to see more details!

[190mech]

Best Ryger theory Ive seen yet;

https://www.youtube.com/watch?v=gOAg...ature=youtu.be

https://www.youtube.com/watch?v=7UfM...ature=youtu.be

[husaberg]

Best Ryger theory Ive seen yet;

https://www.youtube.com/watch?v=gOAg...ature=youtu.be

https://www.youtube.com/watch?v=7UfM...ature=youtu.be

Yes and if you add another pumping chamber below the plate communicating with the upper chamber when the piston reaches TDC controlled between the two chambers by a simple flat reed ala Flat plate RG50.
Over 100% cylinder filling can be achieved, as the mixture will also be compressed twice.
This way an aditional intake will take place also while the piston is descending.
It should also cushion the change in velocity both at TDC and BDC.
The mixture intake flow should also be continuous between the two separate chambers rather than start stop. So a small carb will still work efficiently.
The compressed mixture should also take less time to enter the cylinder.
Pretty sure RicM has posted here before or was it Pitlane?

[Flettner]

What do you think Ken, close to the money, tight fitting pump for off pipe then tuned length of the pipe straight from the carb through the cylinder via direct ports for high revs.