ESE's works engine tuner

[wobbly]

Must have missed something, but I am still searching high and low for a real dyno printout of a FST, or a Ryger for that matter.

[Pursang]

Pursang - you have it arse about face.

I get that a lot.

You don't want 2.5 psi at low rpm , less is better.

Low Pressure = Low Density / Low Temp > Slow SoS + Weaker pulse
High Pressure = High Density / High Temp > Faster SoS + Stronger Pulse

So the Low pressure & slower SoS is to make the pipe seem longer?
The waves travel faster than the gasses, I was thinking that a stronger return pulse might be useful at the the lower end of the band.

So a small stinger would need a blow off that dumped pressure at low rpm, then closed off to raise the pressure as speed went up.

If Bleed diameter is 'too small' at high speed, then mass flow through the engine will be restricted and so will peak power output.

Cheers, Daryl.

[TZ350]

What about an undersized stinger/nozzle and a blow-off valve regulating pipe bleed pressure to maintain (say)2.5 psi at all engine speeds?
Often thought about it, never found any reference, anywhere. More bottom end and over-rev without ignition retard. Cheers, Daryl.

I have tried it, an expansion chamber pressure bleed, see the posts below for pictures and dyno graph.

I have been having trouble with detonation in over rev and I hope to cure it by bleeding some of the pipe pressure off.

The mid chamber bleed. Tried it open and closed, Red open, Blue closed. The big surprise was how quiet it was when open, hardly any more noise at all, certainly wouldn't need any sort of muffler.

[jamathi]

Must have missed something, but I am still searching high and low for a real dyno printout of a FST, or a Ryger for that matter.

Yes Wobbly, and I think we will never see one.....

Did you already test the ceramic coated exhaust duct?

[Pursang]

I have tried it, an expansion chamber pressure bleed, see the posts below for pictures and dyno graph.

Thanks TZee & Wobbly,

So much good info buried in this thread.

I definitely need to adjust my thought process, but there is potential for broadening power bands with pressure bleed management.

Cheers, Daryl.

[TZ350]

.
Just had to give the Piezo thing another go before giving up and going down the ion sensing rout.



9mm Piezo disk glued to a plastic button with a really short connecting hose to absolutely minimize the dead space in the system.



And wouldn't you know, it worked. Gives an identifiable signal all the way to 12,000+ rpm.

Blipping it up in the shed. Motor a little rich in the mid range. But there is an identifiable signal all the way up to 12,000 rpm. And the signal drops off during over run as you would expect and comes back under acceleration again.

[Jannem]

I get that a lot.



Low Pressure = Low Density / Low Temp > Slow SoS + Weaker pulse
High Pressure = High Density / High Temp > Faster SoS + Stronger Pulse

So the Low pressure & slower SoS is to make the pipe seem longer?
The waves travel faster than the gasses, I was thinking that a stronger return pulse might be useful at the the lower end of the band.



If Bleed diameter is 'too small' at high speed, then mass flow through the engine will be restricted and so will peak power output.

Cheers, Daryl.

If I get this right, the smaller bleed could would work at the low rpm, if the pipe was tuned to that range. In practise, the pipe is tuned to high rpm, and bigger bleed helps low because it reduces the detrimental effect of the out of tune return wave.

[lucf]

Must have missed something, but I am still searching high and low for a real dyno printout of a FST, or a Ryger for that matter.

It's about what I have to tell about the FST system after 10 years and nothing else.
If you read it well, you will ask relevant questions, otherwise you have to read it over again and again, till you understand what I did write.
Only relevant question will be answered.


The reason to post this is:
1. That the whole story should be known and not only some details.
2. I did not work on the system for many years, but this doesn't mean that it stays that way.
3. I got hundreds of ideas from all over the world how to do, but I never saw one which was bright enough to try.

FST a new twostroke design
Foekema Symmetric Twostroke

Forword
The first FST text was published on 19 january 2008. 3 month later on 16 March 2008 at 20.00hr the first FST engine was started in my home and my wife Hetty did make the movie on YouTube. One day later Jan Thiel called me to congratulate me, that was close before he went to Thailand.

first start of the engine March 16, 2008 https://www.youtube.com/watch?v=jtTc7sk8WS8

Now, more than 10 years later it is still not successful, yes it runs, but not in the way it should do. Partly due to the speed defined by the mixing of fresh and burnt gases, the fresh gases thus go too far directly into the exhausts. Therefore the temperature of the exhaust stays to low and so the speed can not increase further. It is therefore far from optimal cylinder filling and so it can have no power. Yes this was directly be heard during the first start and it was with adjustment, what I initially thought, not to get out. The solution must be sought in the process. The scavenging is also expected as very critical and needs to be improved in some way. And may be some day it will run, with new idees it is not impossible, I'm still working on it.

What do we know at this moment
1. In the 20s of the last century there were already engines with this system,
2. In the 50s there were Russian coxmotortjes model for this system,
3. In 1986 a patent for granted in England, but without a sequel,
4. Rotax has tested it expanded in 1989, without success
5. Frits Overmars has published his idee more than a month after my FST, and still he only has a printed cylinders. While he wrote in his publication: " Luc it is all about who has the first running engine "
6. He called it FOS, but should have called it DOS, because he got the idea from Cees van Dongen in 1969, that's why it took 30 years like he wrote.
7. Ken Seeber 29 July, 2013 wrote he had the idea in 1984, but not 100% TA, read below

And what about those engines in the 20's. That answer is quit simple, those engines are not 100% TA and had no expansion exhaustpipes and therefore only runs in low engine speed with very low power. My prototype that runs after 3 months, had much more speed, but not enough, what it should be. Even without proper exhaust pipes like those Russian glowplug motors it can run for sure. However, in both cases, with much less port surface and therefore also with less engine speed and so very low power is available. What for me was the real reason to start this project.

What actions now?
Seen together it seems that it is never going to work. Does it still feel like there's still time to stabbing? From Frits I have not heard that he is going to stop it, much hurry he did not seem te have, after what is now known. Does it still make sense for me? No and Yes, No, because I do not have the impression that I could do it better than Rotax. Yes because I do have the engine, the cylinder and the exhaust pipes, so why not try something else? I am now 70 and still do not feel to be too old to learn. I'm looking for new idees to solve the current problems. Read below how it all started.


First publication of this new 2 stroke process
website: http://www.geocities.ws/lucfoekema/FSTsystemNL.html


Original text of January 19, 2008

FST a new twostroke scavenging system. About 2 years ago I got the idea to change the way of scavenging of the twostroke engine. The current way of scavenging exist almost from the beginnng of the 2-stroke history and never changed, unless the many other systems which had been founded. But thinking to get more power you automaticly come to new ideas. So to me it came about two years ago, and that is the Foekema Symmetric Twostroke (FST).

It was not my intention to announce this new idea before making and testing it, but I was supprised when reading the magazine of Kickstart of january this year. Frits Overmars also got a new idea, which he called the FOS system. When reading, I thought: "I'm not sure, but it could be the same". Lucky for me he didn't explain the system, otherwise he would be the first. May be it is different, than we will have 2 new systems at almost the same time. The idea is not very difficult, but realising ideas like this is not that easy, because it has to be made very precisely.
Many things in two-stroke tuning has been made since the beginning of the two stroke. That is why I thought that someone else already did the same in the past. Till sofare I didn't want to spend time for this because there are many more important things to do when you wanted to be the fastest 50cc sprinter in the world on the 150 meter and the 1/4 mile.

The only thing I did was an announcement on the Kreidler.nl site, but without an explenation. Also I did tell it to some friends. But because in the current circumstances, I can't wait to explain my new system. That's why I like to introduce you the "Foekema Symmetric Two-stroke" (FST)
Who would be the first realising the idea in a working prototype is another question. Althought this system should produce more power than the current way, it still is the question, if in practice this will be prooven.

FST scavenging
Symmetric is one part to explain the system, but most important is the 100% Time Area. The whole scavenging will proceed in a symmetric way. After burning the gasses, when the piston goes down, the 4 exhaustducts opens first at the same time and the burned gasses leaves the cylinder. These ducts are fully symmetric around in the cylinder, so the gasses can flow into the 4 exhaustpipes very fast. After that, all symmetric transfers opens also at the same time and fresh gasses flows from all directions right over the piston to the center of the cylinder. This result in a flow of the gasses in the direction of the chamber, while pressing the last burned gasses to the edge of the cylinder. In the chamber the fresh gasses will turn around in the direction of the four exhaust ducts, behind the burned gasses.
So two rows of fully symmetric and 100% Time Area ports. The upper 4 ports are exhausts, the lower row are transfers. Which results in much maximum Time Area capacity, which is 100%. There is no more room left for ducts.

Advantage of FST scavenging
The big advantage is that the whole scavenging will proceed much faster than in the current two-stroke way, because of the maximum TA capacity. That is why a much higher rpm is reacheable with the same or even a lower duration of exhausts and transfers.
Beside this there is another great advantage the symmetric scavenging keeps the temperature in the cylinder completely the same all arround. In the current way there are always risks that one side of the cylinder is more hot than the other side.

There is much more to read and to see if you follow the link, which is public, in Dutch and English
https://www.facebook.com/notes/luc-f.../4085704360035
or here website, which is not up to date, because I don't have access anymore: http://www.geocities.ws/lucfoekema/FSTsystemNL.html

.[/QUOTE]

[F5 Dave]

Oh Jebus, show us a sign.
Like a finger wavering nervously over a clutch lever.

[Pursang]

If I get this right, the smaller bleed could would work at the low rpm, if the pipe was tuned to that range. In practice, the pipe is tuned to high rpm, and bigger bleed helps low because it reduces the detrimental effect of the out of tune return wave.

This is a definite possibility, like everything in 2T there are compromises & multiple solutions. The basic thrust of the ESE thread is for peak power outputs for racing, confirmed by Sims & Dyno & Race Results. There are other applications.

Cheers, Daryl.

[Frits Overmars]

I tend to agree. This system must be looked at quite separately from the Ryger debacle. You've been very frank about what you've seen as the failings of this layout - and at this point I think it is probably a blind alley. But if someone does not at least shine a light up these alleys we'll never know if they're worth pursuing. From where I'm sitting it looks like both the Bradshaw/Ryger and the FOS type systems have basic faults with scavenging. Pressure pulse or enhanced velocity scavenging seems to clear the cylinder unevenly (Bradshaw's published results). The FOS system with it's multiple exhausts would seem to evacuate the cylinder too well, leading to probable charge loss. Neither system would seem to develop the rising column of fresh charge shaped to drive out the residual exhaust gases as has been pointed out by SwePatrick.

Grumph, you are entitled to your opinion, but it seems to me that it is based solely on Lucs allegations. I wasn't going to dignify his stories with a reaction, but I cannot allow him to put people on a false tract with his alternative facts. There are too many perversions of the facts, both historically and technically, to go into all of them.
I would have thought he already demonstrated his level of civilisation and credibility before on this forum. You don't need to take my word for it; you can check with respectable people like Jan Thiel, Wobbly Wayne Wright, Neil Hintz, Ken Seeber.

[lucf]

Grumph, you are entitled to your opinion, but it seems to me that it is based solely on Lucs allegations. I wasn't going to honour his stories with a reaction, but I cannot allow him to put people on a false tract either with his alternative facts. I would have thought he's already demonstrated his level of civilisation and credibility before on this forum and others. There are just too many perversions of the facts, both historically and technically, to go into all of them. You don't need to take my word for it; you can check with respectable people like Jan Thiel, Wobbly Wayne Wright, Neil Hintz and Ken Seeber.

We call it in Dutch: "al is de leugen nog zo snel de waarheid achterhaald hem wel"
https://www.kiwibiker.co.nz/forums/s...post1131082527

[SwePatrick]

Luc!

Why does your dynoprintout from Rygerengine have the same graphics layout as your simulation program? (just different colours)




Is it because the dynoprintout of the infamous Ryger is just a desktop/computer product?
Or is your dyno connected to your simulationprogram?

[lucf]

Luc!

Why does your dynoprintout from Rygerengine have the same graphics layout as your simulation program? (just different colours)

Because I take over the original registrated data to an Excel file, so no simulation at all.
The original data I used, are also published in the past, but it looks like nobody wanted to see this.
The only simulation program I use since 2001 is Mota and I know all disadvantages.
For real situations you still can use it, but for experimentations it's almost useless.
Real calculations I do since about 1998 in my own developped software, which is not for sale.
Ryger is impossible to simulate in Mota, I didn't even try it.

[Grumph]

Grumph, you are entitled to your opinion, but it seems to me that it is based solely on Lucs allegations. I wasn't going to honour his stories with a reaction, but I cannot allow him to put people on a false tract with his alternative facts. There are too many perversions of the facts, both historically and technically, to go into all of them.
I would have thought he already demonstrated his level of civilisation and credibility before on this forum. You don't need to take my word for it; you can check with respectable people like Jan Thiel, Wobbly Wayne Wright, Neil Hintz, Ken Seeber.

I've met Wobbly and Neil, Frits. I'm assuming that you've met Luc - proximity at least. Where someone is posting in a second language it's often difficult to establish intent from the content of a post. I looked at the FOS type system information and was prepared to give Luc the benefit of the doubt on that one.
Certainly he's been much more informative there than in any of the Ryger posts. I'm aware that there are a lot of unresolved issues, I can't do anything about them.
I'll shut up therefore on anything concerning Luc.