Hello 2 stroke enthusiast,
Hereby I will inform you about my new 2 stroke system. About 2 years ago, I got the idea to change the way of scavenge of the cylinder. This idea is not very difficult, but realising ideas like this is not that easy, because it has to be made very precisely.
Till so fare I didn't want to spend time for it, because there are many more important things to do when you want to be the fastest 50cc sprinter in the world on the 150 meter and the 1/4 mile.
But I was very surprised when reading the magazine of Kickstart of january this year, that someone else also got also a new idea about that, he called it 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. May be there will come more new 2T systems at this moment, because I heard from good friends, that there are more young people in action with new systems!
That's why I don't want to wait any longer and introduce you the "Foekema Symmetric Two-stroke system" (FST system)
Read all about it on my website
http://uk.geocities.com/racing50cc/FSTsystem.htmlOr read the text below.
Kind regards,
Luc Foekema
Text of the website pageA new twostroke scavenging system the FST systemAbout 2 years ago I got the idea to change the way of scavenging of the twostroke engine. The current way of scavenging is almost from the beginnng of the 2-stroke history never changed. But thinking to get more power you automaticly come to new ideas. So to me it came about two years ago, and what the name already suggest that is a symmetric working scavenge system.
It was not my intention to announce this new idea before making and testing it, but I was supprised when I read the magazine of Kickstart of january this year. Frits Overmars also got a new idea, which he called the FOS system. When reading it, 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. That is why I thought that someone else already did the same in the past. Because many things in two-stroke tuning has been made since the beginning of the two stroke. 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 system" (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
Symmetric scavengingThe word only seems to be enough. The whole scavenge will proceed in a symmetric way. After burning the gases, the the piston goes down, the 4 exhaustports opens first at the same time and the burned gases leaves the cylinder. These ports are fully symmetric and around in the cylinder, so the gases can flow into the exhaustpipes very fast. After that, all symmetric transfers opens also at the same time and fresh gases flows from all directions right over the piston to the center of the cylinder. This result in a flow of the gases in the direction of the chamber, while pressing the burning gases to the edge of the cylinder. In the chamber the fresh gases will turn around in the direction of the four exhaust ducts, behind the burned gasses.
Symmetric system already exist for a kong time. But not full around the cilinder, with full 100% TA capacity. So two rows of fully symmetric ports, the upper 4 ports are exhausts, the lower row of ports are transfers. Which results in much more time area capacity.
Advantage of the symmetric scavengingThe big advantage is that the whole scavenging process will proceed much faster than the current two-stroke system because of the much higher 100% TA capacity. That is why a much higher rpm are 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.
Realising an operating Symmetric systemRealising this system is not that easy, because it has to be made very precisely, because otherwise the scavenging does not proceed symmetric. Each small deviation in transfers or exhausts has a negative influance in this process.
There are still some more details of which some very important to keep in mind. But that I will keep for me, till the system has been ready for operation later this year.
A pitty !!!Yes a pitty for me, because I did prefer to appear one day on an event unespected, with an engine operating with this symmetric system. Altought the news has gone, a well operated system will be the next challence to realise.
Several forums These subject is to find on next forums:
1.
www.kreidler.nl2.
www.scootertuning.net3.
www.2stroke-tuning.nl4.
www.RD350.nl5.
http://zundapp.messageboard.nl6.
www.apriliaforum.
On some of them there is also written about the FOS systeem, in which is clear that nothing of the system has been explained.