ESE's works engine tuner

[WilDun]

Sorry, I haven't digested all this stuff as yet, it's all very interesting.
However, I do remember way back when someone asked Doug Hele (Designer of Triumph's Trident etc.and a very rational guy) what he thought of that very same "straight line" mechanism now being proposed for the Pattakon, he said that it would not be viable because of the gearing necessary and the extra complication involved (words to that effect anyway).

I must say though, that I always found it very interesting but it still needs to be proven, so I will watch with interest to see it being turned into metal!

[wobbly]

" 132? That's houwge ", no its not in relation to the stroke used.
All Jap 250 MX singles now use a stroke of 72 and if you apply the usual ratio of 2:1 the rod should be in the 140 - 145 range.
None do, the 130 option rod for the one year of YZ250 is pretty much the longest.
The most common size for these engines is 125 C to C, and is really way too short.

[Dutch Fisher]

Absolutely typical failure of a W big end cage - this is exactly why they have changed to "proper " racing flat outer faces
with just slots to guide the needles.
In the W design only the very outside edge of the cage is supported ( and wearing ) on the inside of the rod bore, once the silver has gone
from this area then lubrication failure follows directly behind.
Simple copper coated washers and big ends are shit - a failure waiting to occur.
You run Meth - and of course you wash the engine thru with petroil after every startup ?
If you dont the Meth on the bearing surfaces absorbs moisture - it forms rust, then it goes bang.

The bearing size is non standard, none of the major factories list it, 25/32 is the norm.
25 mm solid pins are available in 60.5 and 64mm cheap as chips off the shelf.
EN36B is a better material, it remains more ductile in the core after case hardening,but the costs of grinding and heat treating a one of pin
are a waste of time.

Wob are you able to get PEEK coated cages ex-stock or do have to get copper/silver cages de-plated and sent to a specialist?

Contact names either way?

[J.A.W.]

AFAIR, KX 500 rod is ~145mm C-to-C,
but I'd suggest doing a search on the 'Hot Rods' site - for a suitable dimensional candidate..
Maybe there's a marine/snow craft application that would fit..

[tdc211]

if you are happy to share, please post pictures of your cylinder work.
I have bought an aftermarket 50mm bore Derbi cylinder kit, I'm shocked at how much porting work it requires. This cylinder will also require epoxy to both inner and outer transfer ducts.

here you go.
Epoxy has never come out.

[husaberg]

" 132? That's houwge ", no its not in relation to the stroke used.
All Jap 250 MX singles now use a stroke of 72 and if you apply the usual ratio of 2:1 the rod should be in the 140 - 145 range.
None do, the 130 option rod for the one year of YZ250 is pretty much the longest.
The most common size for these engines is 125 C to C, and is really way too short.

AFAIR, KX 500 rod is ~145mm C-to-C,
but I'd suggest doing a search on the 'Hot Rods' site - for a suitable dimensional candidate..
Maybe there's a marine/snow craft application that would fit..

Lucky enough there is the 500 rods that suit most of the 250's
I was pretty surprised at how long the Maico rods were but so were the 500's
MODEL LENGTH S E EYE WIDTH C/PIN DIA C/PIN LENGTH
MAICO 250 (EARLY) 125.00 18/22 16.00 25 58.50 93.7309
MAICO 250 (LATER MODELS) 132.00 18/22 17.00 25 57.00 93.7310
MAICO 400/440/490 137.00 18/22 17.00 25 64.00 93.7410
MAICO 490 (LATEMODEL) 137.00 18/22 20.00 25 67.00

I have found a few ultra long rods for the 250 sizes to follow.
Click on it 3 times

[manolis]

Hello WilDun.

The linear mechanism was proposed before 1900 (steam engines, internal combustion engines).

If you remove the inertia loads from the gear-wheels (they increase with revs square) you have a way more reliable mechanism.
How?
By introducing proper counterweights on the rotating / revolving shaft (that one with the small gearwheel), as in the drawings.

And if you use proper materials, width of gearwheels and surface hardening, the mechanism can be as reliable as necessary (by the way, the load capacity increases a lot when an internal gearwheel is meshed with an external gearwheel: think of the shape of the cooperating surfaces).

Thanks
Manolis Pattakos

[manolis]

Hello Husaberg.

You write:
“The rotary valve prototype is interesting not unlike the Coates and the Aussie (Deane) only done differently.
The prototype engine is fashioned/fabricated together in the manner of the Autounion f1 engines. Neat»

I don’t know what the Aussie (Deane) rotary valve is. If you mean the F1 Bishop / Cross rotary valve design, I know it. If you mean something else, please let me know.

The Coates spherical rotary valve and the Bishop rotary valve are substantially different than the PatRoVa.

There is no similarity with Coates, at all.


Quote from http://www.douglas-self.com/MUSEUM/P...aryValveIC.htm

For almost all its history, the preferred valve for the Internal Combustion engine has been the poppet type. (the etymology of the word "poppet" is an interesting study in itself, but a bit off-topic) There are good reasons for this; see the Appendix on the advantages of the poppet valve.

However, many inventors have been attracted by the apparent simplicity and the uniform motion of rotary valves of one kind or another. There is also the tempting prospect of being able to run on inferior fuels because there was no hot exhaust valve always present in the cylinder to trigger pre-ignition. However, as with both steam and IC rotary engines, the simplicity was more apparent than real, and the engineering problems were daunting.

The basic problem, is that the pressures in the cylinder of an internal combustion engine are high, due to both the compression stroke and the explosion of the fuel-air mixture. This produces large forces on the valve system, however it is contrived; the beauty of the poppet valve is that such forces simply push it harder against its seat, and have no effect at all on the valve-actuating mechanism.

However, the geometry of rotary valve systems is inherently different; in the Aspin concept below, the vertical valve cone is pushed up axially against the cylinder head, while the horizontal Cross valve is pressed up against the top half of the bearing surfaces. In both cases this can cause excessive friction and seizure, the root of the problem being that enormous forces are acting on the valve while it is moving.

End of quote


The abovementioned problem of the rotary valves is also a problem of the Coates



and of the Bishop



designs: the higher the pressure into the cylinder (imagine a heavily supercharged engine, or the rotary valve during a short knocking period), the more the valve is pressed up against the cylinder head.

Think:
Does the PatRoVa rotary valve solve this long existing problem?

I say yes.

If you just leave the PatRoVa rotary valve on the cylinder head without any support by bearings, the valve stays there – unsupported – no matter how much pressure you put into the cylinder:




There are other advantages, too:

For instance, the Coates design has a hot exhaust port on the cylinder head (sealed by the red hot exhaust spherical rotary valve) and a cold intake port (sealed by the intake spherical rotary valve). This limits the compression ratio.

For instance, any leakage of compressed gas from the Coates exhaust port, goes to the exhaust, while any leakage of the PatRoVa is recycled and burns during the next combustion.

For instance, you can easily lift the PatRoVa rotary valve a few mm to change the timing / overlap.


Thoughts?
Objections?

Thanks
Manolis Pattakos

[husaberg]

Hello Husaberg.

You write:
“The rotary valve prototype is interesting not unlike the Coates and the Aussie (Deane) only done differently.
The prototype engine is fashioned/fabricated together in the manner of the Autounion f1 engines. Neat»

I don’t know what the Aussie (Deane) rotary valve is. If you mean the F1 Bishop / Cross rotary valve design, I know it. If you mean something else, please let me know.

The Coates spherical rotary valve and the Bishop rotary valve are substantially different than the PatRoVa.

Quote from http://www.douglas-self.com/MUSEUM/P...aryValveIC.htm
For almost all its history, the preferred valve for the Internal Combustion engine has been the poppet type. (the etymology of the word "poppet" is an interesting study in itself, but a bit off-topic) There are good reasons for this; see the Appendix on the advantages of the poppet valve.
However, many inventors have been attracted by the apparent simplicity and the uniform motion of rotary valves of one kind or another. There is also the tempting prospect of being able to run on inferior fuels because there was no hot exhaust valve always present in the cylinder to trigger pre-ignition. However, as with both steam and IC rotary engines, the simplicity was more apparent than real, and the engineering problems were daunting.
The basic problem, is that the pressures in the cylinder of an internal combustion engine are high, due to both the compression stroke and the explosion of the fuel-air mixture. This produces large forces on the valve system, however it is contrived; the beauty of the poppet valve is that such forces simply push it harder against its seat, and have no effect at all on the valve-actuating mechanism.

However, the geometry of rotary valve systems is inherently different; in the Aspin concept below, the vertical valve cone is pushed up axially against the cylinder head, while the horizontal Cross valve is pressed up against the top half of the bearing surfaces. In both cases this can cause excessive friction and seizure, the root of the problem being that enormous forces are acting on the valve while it is moving.
End of quote


The abovementioned problem of the rotary valves is also a problem of the Coates


and of the Bishop


designs: the higher the pressure into the cylinder (imagine a heavily supercharged engine, or the rotary valve during ), the more the valve is pressed up against the cylinder head.

Think:
Does the PatRoVa rotary valve solve this long existing problem?

I say yes.

If you just leave the PatRoVa rotary valve on the cylinder head without any support by bearings, the valve stays there – unsupported – no matter how much pressure you put into the cylinder:



There are other advantages, too:

For instance, the Coates design has a hot exhaust port on the cylinder head (sealed by the red hot exhaust spherical rotary valve) and a cold intake port (sealed by the intake spherical rotary valve). This limits the compression ratio.

For instance, any leakage of compressed gas from the Coates exhaust port, goes to the exhaust, while any leakage of the PatRoVa is recycled and burns during the next combustion.

For instance, you can easily erase the PatRoVa rotary valve a few mm to change the timing / overlap.


Thoughts?
Objections?

Thanks
Manolis Pattakos

I might have to have another look but I was referring to it being similar in that it was a rotary valve EX.
The Deane Rotary Valve is here.
http://www.kiwibiker.co.nz/forums/sh...and-prototypes

FLETCHER TWO-STROKE

http://www.users.globalnet.co.uk/~pa...cc/arc0563.htm

Attachment 314340 Attachment 314342
Attachment 314341
The unusual components showing the cylinder head and static "piston",
the mobile ported sleeve and the cylinder barrel proper.

I like this one it might not work that well but it is odd.

Barr and Stroud this article was written in 1990
Attachment 314186 Attachment 314187
Remember click on them about 3 times.




The Coates design I first seen in the 1990's they had claimed to have the heat licked with ceramics, I am picking they didn't.
Funny enough it was the exact pic they still use

[WilDun]

Hello WilDun.

The linear mechanism was proposed before 1900 (steam engines, internal combustion engines).

If you remove the inertia loads from the gear-wheels (they increase with revs square) you have a way more reliable mechanism.
How?
By introducing proper counterweights on the rotating / revolving shaft (that one with the small gearwheel), as in the drawings.

And if you use proper materials, width of gearwheels and surface hardening, the mechanism can be as reliable as necessary (by the way, the load capacity increases a lot when an internal gearwheel is meshed with an external gearwheel: think of the shape of the cooperating surfaces).

Thanks
Manolis Pattakos

Manolis,
I must point out that Doug Hele at the time, was working for a company who were on the "slippery slope" and not prepared to put much (any) money into developing something new, so he could be forgiven for saying what he did say! - this was just a question which was fired at him by a reporter and didn't really have much significance at the time.
I was actually very interested and tried to figure out why he didn't consider it, but now I realise why, (no money).

The gearing does also remind me of the gearing as used in the Wankel engine and that never seems to give much trouble.

I'm sure that today you already realize just how difficult it would be to coax the 'powers that be' to abandon their deeply entrenched ideas and faith in the conventional four stroke engine! and even though you may have a superior product - it's not just an engineering problem, it's also a marketing problem, and psychology to win people over also comes into play here!

Really I'm just an interested bystander and no fantastic engineer, so I can't argue much with you on the subject but I must say that it does interest me a lot and I would be very keen indeed to see it work.

[J.A.W.]

Manolis has to get Mark Marquez into his flying machine..

Its about the money.. & the hype.. sadly..

As we all know.. 2-strokes are the inherently superior motorcycle race-mill..
..but for a personal flyer such as Manolis proposes, the 2T mill - its really indisputable..

[manolis]

Hello WilDun

You write:
“The gearing does also remind me of the gearing as used in the Wankel engine and that never seems to give much trouble.”

The two gearings (in the Harmonic engine and in the Wankel Rotary engine) are loaded in a substantially different way.

In the harmonic the meshed teeth of the ring gearwheel and of the revolving/rotating gearwheel finally receive the combustion force acting on the piston.

In the Wankel Rotary the combustion force loads directly the eccentric pin of the power-shaft. The gearwheels are there to synchronize the rotor with the power-shaft (crankshaft).

The gearing of the Wankel Rotary is heavily loaded only during a sudden change of the revs (suppose you brake with the engine: all the energy necessary to increase the angular velocity of the heavy rotor about its eccentric pin of the power-shaft comes from the gearing).


By the way, there are several projects in the http://www.pattakon.com web site.

I will be glad to explain everything.

For instance, and since the Wankel Rotary engine was mentioned, take a look at the PatRE project at http://www.pattakon.com/pattakonRotary.htm



It is a valve-less 4-stroke engine with freer breathing than the Wankel Rotary.
It has four combustions per rotation while the Wankel has one combustion per rotor per power-shaft rotation.

Thanks
Manolis Pattakos

[husaberg]

Hello WilDun

You write:
“The gearing does also remind me of the gearing as used in the Wankel engine and that never seems to give much trouble.”

The two gearings (in the Harmonic engine and in the Wankel Rotary engine) are loaded in a substantially different way.

In the harmonic the meshed teeth of the ring gearwheel and of the revolving/rotating gearwheel finally receive the combustion force acting on the piston.

In the Wankel Rotary the combustion force loads directly the eccentric pin of the power-shaft. The gearwheels are there to synchronize the rotor with the power-shaft (crankshaft).

The gearing of the Wankel Rotary is heavily loaded only during a sudden change of the revs (suppose you brake with the engine: all the energy necessary to increase the angular velocity of the heavy rotor about its eccentric pin of the power-shaft comes from the gearing).


By the way, there are several projects in the http://www.pattakon.com web site.



I will be glad to explain everything.

For instance, and since the Wankel Rotary engine was mentioned, take a look at the PatRE project at http://www.pattakon.com/pattakonRotary.htm



It is a valve-less 4-stroke engine with freer breathing than the Wankel Rotary.
It has four combustions per rotation while the Wankel has one combustion per rotor per power-shaft rotation.

Thanks
Manolis Pattakos

That one reminds me of the Prop/rotar set up of the fletner.

[manolis]

Hello Husaberg.

Yes, it seems like the Flettner design (and the Kaman design) but the PatRE needs no gearwheels (not one).

The synchronization is a "built in" affair.

Thanks
Manolis Pattakos

[WilDun]

It is a valve-less 4-stroke engine with freer breathing than the Wankel Rotary.
It has four combustions per rotation while the Wankel has one combustion per rotor per power-shaft rotation.

I think that engine must be inspired by the "cat and mouse" type engines many of which have been developed, but never made it. However, this was also the case with "wobble plate" axial engines and now Duke Engines here (In new Zealand) have developed a seemingly very successful engine using wobble plate principle, complete with sliding valve technology.
So (as with the Pattakon,) they have persevered with what appeared to be a failed idea, until they eventually came up with one that works very well!
- but as I said before, next big hurdle is to change a deeply entrenched mindset!