ESE's works engine tuner

[jasonu]

Do blip, just cant hear it on the 2T, but I've got no excuse for the ugly over-rev going into 2nd gear
Glad to hear you've joined the dark side. Most fun bike ive ever ridden the NSR. If you want to know anything that we've done just ask, I can give you all the files for the billet heads and head inserts that I'm running if you're keen.



Got a good radiator now, sitting anywhere from 55-60 depending. Still haven't done any ducting though so it's not being very efficient with it's air flow. Good to know I have extra cooling up my sleeve for when we get into summer.

I thought they (rightly) separated motard style wide handle bars bikes from the rest of the rabble for safety reasons.

[Tunisti]

Greetings from Finland!

I´ve been reading this thread for couple of months, and decided to join the conversation for the first time.

Some Ryger speculations: One of my fellow tuners Pauli had this idea of cylinder extra (A) ducts, which would be positioned above the transfers and also partially above the exhaust port. Those ducts would lead down to the cylinder and end up as ports that could be opened and closed by the piston skirt. I thought that speculation bit further and decided, that there could be another (B) ducts coming from inlet duct (after the carburator, before the main reeds), which would involve reeds. Those ducts would join the first mentioned ducts near the lower ports.

There's some ultra HD pictures to give a glue of what I mean:
http://i893.photobucket.com/albums/a...pskgjaszxo.png
http://i893.photobucket.com/albums/a...psahkcwkni.png

And now the theory behind that mess (note new terms):

Step 1: Ryger ports open, and the purging exhaust gases force the fresh mixture inside Ryger ducts into the crankcase. Soon after that the piston skirt closes the lower end of the Ryger ports and the pressure and mass of the mixture in the crankcase has risen. The Ryger ducts are now somewhat full of exhaust gases.

Step 2:Exhaust port opens, and the high pressurised exhaust gases in the Ryger ports flow back into the cylinder, until the pressure in ducts is equal to cylinder pressure. Cylinder pressure drops as exhaust gases pass to the pipe.

Step 3 (option No.1): Transfer ports open, and the high pressurized mixture enters the cylinder. Soon after that the pipe starts to suck the cylinder, and the reeded B-ducts start to flow from the inlet duct. Exhaust gases in the Ryger ducts flow into the cylinder, and after the exhaust gases have been replaced by the fresh micture, the ryger ports act as "pulse transfer" which are purely powered by the suction of the pipe and the inertia of the mixture flowing throught the inlet duct. The cylinder is scavenced rapidly and efficienty, due to high crankcase compression and large total transfer area (conventional transfer + Ryger ports). In this option the pipe starts to suck at such a point, that the exhaust gases in the Ryger ports don't get mixed too much with the fresh mixture coming from the conventional transfers.

Step 3 (option No.2): Similar to option No.1, except that the exhaust sucktion pulse is delayed such amount, that the exhaust gases inside the Ryger port intentionally mix with the fresh mixture coming from the conventional transfers, causing the mixture to have good HCCI characteristics.

Step 3 (option No. 3, Pauli´s original idea): In this scenario, there are no B-ducts involved. The Ryger ports only pressurize the crankcase, and are mostly full with exhaust gases (in other words, exhaust gases are mixed with the fresh mixture inside the crankcase). The suction made by pipe would mix the exhaust gases in the Ryger ducts into the somewhat fresh charge in the cylinder, giving the needed HCCI characteristics. The Ryger ducts would be in a state of vacuum, when te pipe sucks the exhaust gases out of the ducts. Also there would be some flowback of fresh mixture from cylinder to the Ryger ducts (and crankcase in opt. 1&2), when the exhaust pulse arrives. Flowback could also occur at the moment of exhaust port being closed and Ryger ports being somewhat open. That could be a big issue in all of these structures.

Step 4: All the ports are closed, and depending on the Step 3 options, there would be more or less exhaust gases being mixed in the fresh charge. After that the best guess is that some kind of HCCI ignition would occur, maybe due to somewhat homogenous mixing of exhaust gases. (Maybe the trick is to heat the mixture with exhaust gases, without actually heating the incoming charge -> no "density losses" in induction/scavenging. Could there also be some "knocking dampening" characteristics with the "dirty mixture", allowing the combustion to be knocking-like without the aspects being able to destroy the engine...?)

Btw. Is it okay to introduce own achievements in this thread?

PS. Sorry for my bad English!

[MotleyCrue]

True, but there is more to it. The Ryger engine makes us face the fact that conventional combustion is anything but perfect. Trapping all the fuel in the cylinder is one part of the equation; getting it all to burn completely is part two.

It runs with a form of preignition (not HCCI) which 1) burns better and 2) keeps the parts from flying out the top at 30000 rpm. The better burn compensates for the added pressure towards end of compression. The exhaust dilution keeps the NOx emissions in check like it does for 4 stroke engines.

[Muciek]

Another 500 GP "replica"
http://www.morebikes.co.uk/scoop-sut...hp-two-stroke/

Video https://www.facebook.com/mediagarage...13073/?fref=nf

Dunno why they used BxS 56 x 58,5.

[TZ350]

Btw. Is it okay to introduce own achievements in this thread?

Own achievements is what this thread is mostly supposed to be about plus a bit of learning and sharing.

I would love to see a few pictures of what you have been doing and hear about what you have achieved. Anything is welcome that we can learn from.

[breezy]

Frits said..
"True, but there is more to it. The Ryger engine makes us face the fact that conventional combustion is anything but perfect. Trapping all the fuel in the cylinder is one part of the equation; getting it all to burn completely is part two."

so as this engine was developed to make a clean burning 2 stroke, Mr Ryger must have found out what percentage of the trapped fuel about to be combusted was actually combusted.. maybe the combusted fuel actually moves quicker out of the cylinder through the exhaust port and leaves the un used fuel trailing slower behind. this could be trapped/mixed and cooled with new fuel flow into the cylinder basically recycling unused fuel from previous cycle...:sherlock

[MotleyCrue]

It runs with a form of preignition (not HCCI) which 1) burns better and 2) keeps the parts from flying out the top at 30000 rpm. The better burn compensates for the added pressure towards end of compression. The exhaust dilution keeps the NOx emissions in check like it does for 4 stroke engines.

If the preignition is controllable no harm done. Regular engines cant control preignition.

[Tunisti]

Well, I think that me and my friend have the fastest moped in Finland. Actually it´s not a moped, still <80cm3. We´ve been building mopeds and two stroke parts with very small budgets in our garage. The top speed of the "record" moped is 134,6kph, 0-100kph is about 9,5s and 1/8mile goes just under 11 seconds. Pretty moderate specs I´d say... Motor is Suzuki EPO type air cooled 5-speed moped motor, stroke 37,8mm and bore bit over 50mm.

Here are some pictures of "Raisu":




Copyrights jokelaj.kuvat.fi

We have also done some experimental DIY cylinder castings, with zero budget and knowledge. One lostfoam casted prototype cylinder is in active usage, and two sand mould casted cylinders ended up as failures.

Lost foam casted cylinder:



And some failed sand castings:


We have also made DIY aluminium melting furnance, DIY inertia dynamometer, lots of special modifications to commercial cylinders and all the aerodynamic coverages of the "Raisu". Most of the components that we have used are from scrapyard or second hand markets.

Dyno results of Raisu, three differently modified cylinders and some exhaust pipes we´ve made, you can find a lot more in here (on the left, more pictures about castings): http://s893.photobucket.com/user/Tun...?sort=3&page=1



And here is our YouTube channel: ¨https://www.youtube.com/user/RKTeamFinland/videos

To pick something up, here´s some 1/8mile acceleration: https://youtu.be/pTgZ7B7fhh8?t=19s

Sorry if too many pictures!

[Flettner]

Good on you Finnish barstards, yes more casting stuff (pictures etc) would be nice. On this thread would be ok but there is also a Bucket Foundry thread as well, dedicated to casting and general making of things engine (and other). We would all love to see what you get up to, casting wise

[Flettner]

I've experimented with ceramic coating before, It has the ability to transfer heat slowly so you get a cool piston / combustion chamber with a hot skin promoting detonation as the engine starts working hard. For this reason I binned the idea but if you were to design a combustion chamber that could control when and where this detonation started AND control the distribution of the subsequent burn, be it a high speed burn.Might work? Perhaps a small annular groove around the inner edge of the squish area close to the combustion chamber?

[FastFred]

We´ve been building mopeds and two stroke parts with very small budgets in our garage.

We have also done some experimental DIY cylinder castings, with zero budget and knowledge. One lostfoam casted prototype cylinder is in active usage, and two sand mould casted cylinders ended up as failures.

This is great stuff, thanks for the photos.

[MotleyCrue]

I've experimented with ceramic coating before, It has the ability to transfer heat slowly so you get a cool piston / combustion chamber with a hot skin promoting detonation as the engine starts working hard. For this reason I binned the idea but if you were to design a combustion chamber that could control when and where this detonation started AND control the distribution of the subsequent burn, be it a high speed burn.Might work? Perhaps a small annular groove around the inner edge of the squish area close to the combustion chamber?

I dont think you would want detonation. I would think preignition like RC 2 stroke engines but maybe not initiated by the same mechanism.

[Flettner]

Frits, has HR-HCCI been tried with other fuels like ethanol or perhaps LPG?

[Frits Overmars]

Frits, has HR-HCCI been tried with other fuels like ethanol or perhaps LPG?

I couldn't say; what is HR-HCCI?

[2005bully]

Tunisti

You have a TON of time invested in what you have done there. The hydro-formed pipes you have pictured are my favorite. It takes a great deal of patience and skill to make one come out that good. If you have any more pictures of the details I'm sure many on here would like to see them. Kermit Buller