ESE's works engine tuner

[ken seeber]

Hi,

One thing about Ryger engine, which might have been expected, and it has proved after first static test, it is very low mechanical noise.

In terms of low mechanical noise, this is pretty subjective in that it also depends when this observation is made. For example, a typical KZ piston might have a “drop” over its length (difference between the max dia at skirt to the top land) of 0.3. Add to that a typical cold fit clearance of 0.07. So, 0.07 at the base of the skirt and 0.37 at the top. Pretty sloppy in anyone’s language. And nothing really to stop the piston rocking from side to side, almost rolling about the skirt. It’s gotta be noisy and they are.
However in the Ryger situation, we have the main piston connected rigidly to the smaller/guiding piston. Apart from what I would expect a small clearance for the smaller piston, the main piston is fundamentally prevented from rocking. Perhaps taking up the cold clearance at most.
When an engine is at power operating temp, the ideal situation probably is that the bore is round and straight and the piston has expanded much more at the crown and is almost cylindrical, ie a constant clearance at all positions. Whether the engine is as mechanically noisy under these conditions is unknown to me as there are many other noise sources that would dominate, ie exh and inlet.
End of the bullshit, however I can’t help but agree that the Ryger might rattle less when cold, at least and that can only be a good thing.

[SwePatrick]

Without any proof or other evidence of that Ryger engine actually working as stated i get the feeling it´s only smoke and screens to get new investers spend money, to secure some guys income without actual work.
Very common actually, getting investors to spend money on highrisc projects.
Often, very often this is conned by old guys figured out how to rip money off those rich people.

And it stinks Gizmondo....(google: https://www.google.se/webhp?sourceid...tefan+eriksson)

[SwePatrick]

A little trip back in time regarding using concrete constructing dynorollers.
DO not!!!!!!!!! use concrete on the outside of the steeldrum
A friend of mine bought this little dyno, i warned him.
He spun the rollers almost 2000rpm,, BLAM!!!

Fortunatly no one got hurt.
And the 'megafortunatly' was that a guy stood directly behind the rollers when it went off.

Rgds
Patrick

[philou]

Dyno it is a product sold commercially as dyno ?

[katinas]

As Katinas wrote earlier, nor his engine, nor the Ryger has auxiliary exhaust ports because those would require a wider piston skirt, that would in turn hamper the flow into the transfers. Since I read it here, I can react without endangering my NDA (thank you Katinas). And what follows now, is purely my own guesswork since I never received any relevant information from Ryger.
From the Ryger homologation papers we can see that the exhaust timing is lower than the Aprilia RSA timing, so the Ryger's blowdown angle.area is tiny compared to the RSA's. And when taking the initially quoted maximum torque rpm of 17500 into account, the Ryger's blowdown time.area was almost non-existent. It nevertheless did not stop it from producing over 70 hp.
And before anybody says that they've never seen any proof of this amount of power in the form of a real dyno graph, let me say that neither have I, but I was lucky enough to get a seat-of-the-pants impression of the original Ryger prototype before problems with the production engines brought the operation to a halt, and my pants are not that easily fooled, having ridden motorcycles with several hundred hp.
By the way, what made me decide to step out of the project, was the lack of frankness. I would have loved to take part in the development of that engine, but it turned out that I was only recruited to generate publicity. I'm sure I could have prevented some of those technical problems if only there had been an exchange of thoughts, but all I ever got were promises. It's a pity....

OK, back to my theory. Seeing that the in-cylinder pressure of the RSA is about 12 bar at exhaust opening, and given that the Ryger is claimed to produce about 20 hp more than the RSA, and given that the Ryger's blowdown time.area is so much smaller, there must be a huge amount of spent gases that enter the Ryger's transfer ducts, raising the pressure in the sub-piston volume and the density of the mixture (well observed, Philou). The higher pressure may lead to a much faster transfer flow, with more mixture inertia. This inertia then ought to pull more fresh mixture through the reed inlet valve.
I only wonder how effective this inertia can function, as the Ryger's transfer ducts are very short and anything but flow-encouraging.

That was also my second impression after the staggering acceleration: the beautiful sound. When you would expect a regular 125 cc engine to reach the end of its power band, the Ryger started to sing; that's the best I can describe it. This lovely sound, in combination with the large amount of hot exhaust gas that enters the transfer ducts and is subsequently recycled into the cylinder, made me think in the direction of Homogeneous Charge Compression Ignition with its very fast, short combustion phase; maybe ten times as fast as regular spark-ignited combustion. HCCI would also account for low fuel consumption, comparatively clean exhaust gases, and the need for only a small cooler, although I could not verify these claims.

Could you persuade your software to take a look at these thoughts, Neels?

Thank you very much for this post. Now, I understand more clearly this "ryger story", and if I read some old posts again, I get the full completely different picture. I can't imagine that conspiracy is possible in such small team working together on so interesting project . Jan and you, four years ago began to reveal so much interesting information about RSA/RSW, that I think this is not just new information about 2 stroke, its new communication level.

Thank you for sharing your excellent knowledge.

[mr bucketracer]

Dyno it is a product sold commercially as dyno ?

looks like a break testing device for very slow rpm

[Haufen]

Like I said, I'm not that easily fooled.

HCCI is very dificult to control, there is no way this can be achieved with a 30mm carb, and it is typically used for lower load applications. What happened when you closed the throttle after a full load run? Was the engine responding with a delay? HCCI normally works with excess air, so even if you'd manage to get the required amount of air in, you'd still be better off, hp-wise, running on the rich side, e.g. AFR 12.

You might want to read what Flettner wrote about it.

Can you provide us with other information - besides your seat of the pants dyno - which would lead to the conclusion that there is actually something more inside this whole ryger story besides a lot of hot air and fairy tales?

And could you provide a link to what Flettner wrote? I don't think I have read what you are referring to. I have read what european and asian oem and some universities have published about the subject of HCCI though. And this is what led to my sentence in the quote above.

HCCI on Wikipedia is a quicker read and not so bad either.

in 2013 for example, a study found that:

5. Conclusion
CAI/HCCI engines still have not met the level of development and cost that would make a market introduction possible at the moment. The technical challenges facing both gasoline
and diesel HCCI combustion are their limited operational range and less optimized combustion phasing, owing to the lack of direct control over the start of ignition and the rate
of heat release. ...

source

And last but not least, F1 would not be running prechamber ignition if they had yet found a way to use full load HCCI.

[marsheng]

Hi Frits

We are modifying a 1970 Kawasaki disk valve 350 twin. I wanted to know if your generic 2s exhaust design is a good starting point or is it for more modern bike?

Alternatively is there a better starting point for a design ?

Thanks Wallace

[Frits Overmars]

Can you provide us with other information - besides your seat of the pants dyno - which would lead to the conclusion that there is actually something more inside this whole ryger story besides a lot of hot air and fairy tales?

No. Like I wrote, the lack of communication was the main reason that I quit the project. And I do not feel any obligation to defend Ryger's claims.

And could you provide a link to what Flettner wrote?

About here: https://www.kiwibiker.co.nz/forums/s...post1130931750

F1 would not be running prechamber ignition if they had yet found a way to use full load HCCI.

I'd love to hear your explanation why Flettner's engine is running full-throttle without a spark and revving like mad.

We are modifying a 1970 Kawasaki disk valve 350 twin. I wanted to know if your generic 2s exhaust design is a good starting point or is it for more modern bike? Alternatively is there a better starting point for a design ?

There are better ways Wallace, EngMod2T for example, but it would require about 50 times as much input values as the simple FOS concept that I wrote to help aspirant-twostroke tuners on their way.
My concept will provide a good starting point, provided that you enter a realistic max.power rpm-value, based on the small angle.areas of that 1970 Kawa.

[marsheng]

I'd love to hear your explanation why Flettner's engine is running full-throttle without a spark and revving like mad.

I had that on my Maico. Throttle closed, ignition off and it sat at around 5-6K. The plug was red hot. Only way to stop the motor was stall it with the clutch. The motor did this while it was being warming up on the Dyno. Throttle closed, ignition off and it sat at around 5-6K.

[jamathi]

Without any proof or other evidence of that Ryger engine actually working as stated i get the feeling it´s only smoke and screens to get new investers spend money, to secure some guys income without actual work.
Very common actually, getting investors to spend money on highrisc projects.
Often, very often this is conned by old guys figured out how to rip money off those rich people.

And it stinks Gizmondo....(google: https://www.google.se/webhp?sourceid...tefan+eriksson)

Exactly my idea too, 2 years of big talking without any proof!
Complete bullshit...
This project seems to be failing in a bad way.
No engines are being sold....although they are for sale now since a couple of month's
No one is believing these people anymore.
Now they will have to proof themselves on a real racing track!
And then there is still the reliability problem....
Spare pistons will not be cheap, after hundreds of them have been made without success.
And piston life will always be quite short, due to the very high lateral forces acting upon it.
Caused by the very short connecting rod.
Now a 50cc version is being made, with some very capable people working on it.
This may be the final proof I think.

[katinas]

I had that on my Maico. Throttle closed, ignition off and it sat at around 5-6K. The plug was red hot. Only way to stop the motor was stall it with the clutch. The motor did this while it was being warming up on the Dyno. Throttle closed, ignition off and it sat at around 5-6K.

It happened in 1991, I was testing motorcycle ( in photo ) with tuned outboard engine "Vihr-30" 488cc two cylinder with discs valve intake, like this ( https://www.youtube.com/watch?v=PQ2wOx2jgTE ). I can't remember whether it happen, on full open throttle or not, I just heard the blast from under seat pipes and then bike began accelerate. Close the throttle, ignition off, but it accelerate. I do not remember how managed to stop, with clutch or rear brake, but when I return to garage with trebling hands, my friend, who saw everything from side laughing told that saw flame from pipes and then bike disappeared.
It never happen again with my any other motorcycles. Maybe after explosion in the pipes, high pressure provoke something in this engine .

[wobbly]

Some may think I am like Luc, talking up shit to justify myself, but we must apologize to Hinson for thinking the clutch was slipping on the RS400.
In fact when it finally had two reed valves working, the 4 off M6 caps holding the cush drive together, sadly, gave up.
Now I have 4 off 8mm Titanium pieces doing the job, so hopefully its reliable again.

[katinas]

Hi Frits,

Maybe you know something about this "half moon" plates in this titanium YZR 500 headpipes. I can only guess.

Thanks

[Ocean1]

Some may think I am like Luc, talking up shit to justify myself, but we must apologize to Hinson for thinking the clutch was slipping on the RS400.
In fact when it finally had two reed valves working, the 4 off M6 caps holding the cush drive together, sadly, gave up.
Now I have 4 off 8mm Titanium pieces doing the job, so hopefully its reliable again.

What are the screws holding down Wob? Like how rigid is the retainer? Those rubbers are going to extrude laterally under load, making for potentially a lot of force just to one side of the screws...