ESE's works engine tuner

[2005bully]

If the timing of the transfer ports is not critical, that leads to the assumption that some method besides symmetrical piston port control is employed to time the transfer of mixture.. Naturally the first thought is control by demand. And since reed technology is what we are familiar with in this context that is our first assumption. But assumptions could also include the timing of the bulk flow of mixture transfer through re-timed pressure differentials. The advantage of such a design in regards to mixture transfer has been documented by Manuel Sevilla Sanz. In the 1980s he pursued an idea of the early DKW engineers to move the majority of the mixture transferred towards the end of the transfer port open period. His method was achieved with a secondary positive displacement piston pump phased to emulate non symmetrical transfer port timings. If a diaphragm type pump were located between the base of the Rygers cylinder and the crankshaft, it could be phased so when the piston uncovers early opening transfer ports the pressure differential above and below the piston is nearly equal. This would result in little initial upward flow through the transfers, but as the cycle continues the pumps phasing would increase the pressure differential and delay the period of time when the bulk of the mixture is transferred. The benefits would include more effective time for blow-down be delaying the time when the bulk of the mixture is transferred. Low pressure differentials at port opening would reduce mixture dilution. Additionally with the fresh mixture spending less time in the cylinder before ex port closing, short circuiting should be reduced.
As to the process the Ryger actually uses, this concept of is pure speculation. Hopefully someone can find it as food for thought... Kermit Buller

[peewee]

bully if it eliminates any fresh mixture from going into the pipe when the exh port opens then wouldnt it need some type of new pipe design because a traditional pipes designed to push mixture back to the cylinder i thought ?

[Lightbulb]

these 2 absolutly do not go together. reads build in 11 ports in a cylinder that looks as simple as a normal 2stroke cylinder can not be "simple".
If I had money to spare, I'd bet there are no reads in the transfers.

I do not believe it has 11 transfer ports. I believe it has 11 sets of reed valves, 6 for induction, and 5 for the 5 transfer ports. You can not think of this in the terms of the normal 2t engine layout with crank case compression. It will have only piston volume compression. So with that the dynamics will be very different indeed. I have not read anywhere that it has 11 transfer ports. 5 is more realistic and all that would be required. As far as reeds go, there are lots of design options for them as well. You have bike type reeds and then their are reeds like what is in a pulse jet and then their are the type that are in wind instruments, like an oboe or bag pipe. These are the things that test the grey matter in deed. Pulse jet reeds are very simple and allow for quite big time area's as well.
Neil

[TZ350]

I have not read anywhere that it has 11 transfer ports.

Hey guys,check this one!!

Sure it says 11 transfer ducts, so your right it does not say 11 transfer ports. And there could easily be just the usual 5 transfer ports.

[2005bully]

Previous post from pee wee.... bully if it eliminates any fresh mixture from going into the pipe when the exh port opens then wouldnt it need some type of new pipe design because a traditional pipes designed to push mixture back to the cylinder i thought ?

You may be correct. Remember this is all speculation...... Looking at the picture of the Ryger pipe, it does appears to be quite conventional..... My thought is that the mixture drawn by the pipe into the ex port would mainly be burnt gasses with perhaps a small amount of fresh mixture. This means there would be a larger volume of burnt ex gasses also pushed back into the cylinder. These burnt gases loaded with free radicals left from the previous combustion cycle would be available to inter mix with the fresh charge trapped in the cylinder for the next combustion cycle. This method without mechanical complications could well simulate the throttled the ex duct process as describe in Hondas exp2 motorcycle research. This research was effective in achieving ARC (ARC is Hondas acronym with the same meaning as the more common acronym HCCI). This might just allow the Ryger to be self compensating with the pipe to achieve Hcci over a broad rpm range. And do so without the power robing restriction of Hondas exhaust duct throttling..... If indeed the process were possible.... In my understanding the appearance of a hi primary compression would limit the volume of mixture that could be moved through the engine at peak BMEP. (limiting the torque peak) But because of greater effective blow down time periods and less loss of fresh mixture at high rpm's the process should greatly extend the engines ability to "overwind".
Its all a puzzle, just trying to take what information is available and match it to a process that fits the clues.

Here is a link to an over view of Hondas research.... http://www.motorcycle.com/manufactur...xp2-14293.html

Here is a link describing Hcci..... https://idea.library.drexel.edu/isla...tream/OBJ/view

Kermit Buller

[breezy]

i hope that vw had nothing to do with the emissions testing ...!!!!!

[wobbly]

The number of ports/ducts has been lost in translation I believe.
In the CIK homologation papers the quantity does refer to the number of holes in the cylinder.
This is set down in stone so that clever bastards don't rearrange the numbers to say turn a transfer port into an extra ex port for example.

[monkeyfumi]

Pictures on the twitter today showed Stan Stephens has built a 1200cc 2-stroke v6 (using Banshee cylinders) Only 3 carbs (in the vee, looks like pairs of cylinders from opposing banks share the inlet.)

Not sure what it's meant to go in, but should be interesting.

[wobbly]

For those of you that dont know ( coz you didnt give her any jumpstart cash ) Av is 2015 European Woman's Cup winner.
Stunning result - and just goes to show , dreams do come true - but you gotta have them first.

[TZ350]

Av is 2015 European Woman's Cup winner. Stunning result -

http://www.https://twitter.com/avgas...521028/photo/1

Av

[Muciek]

https://twitter.com/harleyholeshot/s...55318763560960



Should be around 200Hp?

[peewee]

wob figured you like to see the crank that showed up the other day. yes im using straight cut spur gears . picked up a extra roller bearing and had a groove cut in to use behind the front sprocket. you reckon it should hold together for a good long while ?

[TZ350]

I just love to see these posts and pictures about motors that people are building for themselves.....

[wobbly]

With the centre two bearings located in the case, why do you need to lock the outer bearing races in with clips as well.
There is no side load with straight cut gears.
I would take out the outer clips to let both sides of the crank float, and make sure it does by moving those outer races as far outwards as you can.
This will remove the huge friction setup when everything heats up and the axial clearance on the bearings starts to disappear.
Simply floating the crank ( 0.3mm ) in a 125 single is worth over a Hp.

[peewee]

i havent put a dial indicator on it yet but i will. even with all the bearings clipped it still has some end float. about .3-.5mm judging by feel. they must have set it up like that when it was assembled