the clean two-stroke thread

[WilDun]

Electronics are not the enemy, although mechanicly we can do better than the loop scavenge twostroke, in my opinion.
Combined, we may have something worthwhile.

Yep - it will need a lot of experiment which I really couldn't do in my present situation (perhaps never could!) - there may be a few failures on the way but each failure will be another lesson! - and if there's good electronic equipment and other parts lying around that we could scrounge, we'd be fools not to use it in those experiments! - nobody who invented (or discovered) anything, ever did things entirely ''textbook style" !

[ceci]

I'm sure that is possible - but here is an analogy :-
If you have a wife, go and tell her that she doesn't need a cellphone, a vacuum cleaner, a washing machine or drier and she can't have a car to go and indulge in a shopping spree! - Sure, it will work and she will still be able to survive without these things, but if she is pretty and talented, then she may want to do some more shopping elswhere!

Moral of the story don't cut off the frills entirely - although sensible, you'll lose your 'not so clever' buying public!

You have a PRETTY wife, but she doesn't know how to love, iron, cook, sew, keep the house clean.
What do you do, do you stay with her or change her for the ugly one
The useful is what really counts, the beautiful attracts more but is useless.
Tim trans analyzed all the systems he decided to create his and this one without electronics, why ?: Very simple, cheaper and that works for the whole planet

https://www.facebook.com/media/set/?...5824143&type=3

[Flettner]

You have a PRETTY wife, but she doesn't know how to love, iron, cook, sew, keep the house clean.
What do you do, do you stay with her or change her for the ugly one
The useful is what really counts, the beautiful attracts more but is useless.
Tim trans analyzed all the systems he decided to create his and this one without electronics, why ?: Very simple, cheaper and that works for the whole planet

https://www.facebook.com/media/set/?...5824143&type=3

But does it work? Has he built one? Some results?

[ceci]

But does it work? Has he built one? Some results?

I have no answers to these questions.
What is undeniable is Tim's will to solve the 2S contamination problem.

http://www.pit-lane.biz/t5235-2-stro...-by-tim-hickox

[husaberg]

All very interesting! - but I was going to say why did Honda let the patent lapse? but that was answered by someone - Husa? - it didn't suit their sales strategy at the time, also it was at a time when they were trying to promote change to the four stroke instead!

Still seems strange that they let it lapse - It would indicate that they were not worried about it being used by others as the four stroke had gained enough ground to keep it ahead and no one was willing to take a chance on it and lose their reputation, when they were already doing OK!!

Last century was when breakthroughs were in full swing, this century - refinements and electronic enhancement instead!

But as Frits would say - K.I.S.S!

Patents last 20 years only then its generic technology

[Frits Overmars]

https://www.facebook.com/media/set/?...5824143&type=3

This Facebook presentation was not exactly confidence inspiring:

[WilDun]

You have a PRETTY wife, but she doesn't know how to love, iron, cook, sew, keep the house clean.
What do you do, do you stay with her or change her for the ugly one ................................

No, I would just find her a job and send her off to work instead ....... and I would stay at home, tidying up the house etc. (takes the best part of an hour) then spend the rest of my day designing and building the perfect two stroke! - might even employ a housekeeper! .......... then maybe not - my age might not allow me to do that! - oh well!

[WilDun]

You have a PRETTY wife, but she doesn't know how to love, iron, cook, sew, keep the house clean.
What do you do, do you stay with her or change her for the ugly one ................................

Ceci
No, I would just find her a job and send her off to work instead ....... and I would stay at home, tidying up the house etc. (takes the best part of an hour) then spend the rest of my day designing and building the perfect two stroke! - might even employ a housekeeper! .......... then maybe not - my age might not allow me to do that! - oh well!

Norman
Thanks for that article - that was written just when I was starting to take an interest in motorcycles again after over 25 years off, so I hadn't read much about developments around then.
I found it very interesting indeed and agreed entirely with most of what he was saying , but I had always looked on a two stroke as a competition machine with Schneurle scavenging (as this guy obviously did.) ...... I think Uniflow now!

Since my life had changed dramatically through severe health problems, I could no longer ride bikes (to do so and risk falling off would have been the end for me!) - then I found computers and forums! and have never stopped talking since!

I am still learning and just as keen as I was over 50 years ago, but my ideas have changed and I am more concerned with the fate of the more mundane two stroke and how to make it as clean as these exotic competition machines, but still keep it inexpensive! ..... ie in the future when it might actually need to be the breadwinner (through huge sales in the commuter market etc).

Maybe Ceci is right about ditching electronics I dunno - but why? when it works fine and is actually well developed and relatively cheap!

Anyway thanks for sharing

[Frits Overmars]

Maybe Ceci is right about ditching electronics I dunno - but why? when it works fine and is actually well developed and relatively cheap!

Can we achieve our goal without electronics? If No: use electronics.
Do we need to resort to complicated workarounds in order to achieve our goal without electronics? If Yes: use electronics.
Can you agree with this, Ceci?

[ceci]

This Facebook presentation was not exactly confidence inspiring:

You know that the same method is used in Pierre Duret's IAPAC system, the use of a plenum.
I forgot that IAPAC uses electronic injectors and that will surely work.

Can we achieve our goal without electronics? If No: use electronics.
Do we need to resort to complicated workarounds in order to achieve our goal without electronics? If Yes: use electronics.
Can you agree with this, Ceci?

Perhaps I am the only one in this thread that defends that idea, but over time if we look at the literature we will see great researchers who defended this idea

[WilDun]

You know that the same method is used in Pierre Duret's IAPAC system, the use of a plenum.
I forgot that IAPAC uses electronic injectors and that will surely work.............................................. .
Perhaps I am the only one in this thread that defends that idea, but over time if we look at the literature we will see great researchers who defended this idea

That link you gave us will take (me at least) a while to digest properly and I've only just gone through it once quickly, (probably will need a little while and a couple of "read throughs" ..... same thing for the link Norman posted and then I need to understand the RYGER as well.

I didn't really pay much attention to the RYGER when it was such a controversy on the ESE Thread a few years ago! so finding some more info on that and how it (nearly) worked is on my list! (I'm sure katinas will help there!)

I knew that there was a concerted effort to keep the 4 stroke alive and the 2 stroke at bay (by "skullduggery and misinformation") but didn't actually realize the extent of it all!

However, all this is still only trying to address the "failings" of the Schnuerle type system and patch all those up - I do feel that a complete new design is necessary for the two stroke in general - the OP engine (and uniflow in general) being (to me anyway) a good candidate, despite having maybe a couple of (percieved) disadvantages!

I think there is room for electronics to be used to be an improvement over stark simplicity! especially if it's only being kept simple for the sake of being able to say "this engine is electronics free" we will end up with a smooth operating efficient machine, without a lot of extra cost!

Anyway it's good to see all that pent up passion is still there and beginning to resurface!

[Vannik]

You know that the same method is used in Pierre Duret's IAPAC system, the use of a plenum.
Perhaps I am the only one in this thread that defends that idea, but over time if we look at the literature we will see great researchers who defended this idea

Ceci, I bought that book when it was published, keep in mind it summarizes the research of the late 80's, more than 30 years ago!

Modern electronics, of the last 5 years or so has become a lot cheaper.

[Flettner]

Percived dissadvanges of the OP.
Height or width if you lay it sideways in a bike frame.
Joining the crankshafts.

It can be said two smaller crankshafts is no worse than a single bigger crank with a balance shaft. The two cranks also have the advantage of being simple in design as compared to if the engine was a parallel or vee twin.

Joining..... yes an issue. But if the engine is layed down across the frame with crankshafts pointng forward and aft, a gear set joining them ( four gears ) one being the clutch gear, two connected to the crankshafts and one extra as an idler (I'm sure I could find it a job also), gearbox behind that, CV joint, shaft down to a bevel gear at the rear wheel. Sort of a BMW ish. I've measured against my YZ 250, OP slighly narrower.
This gives lots of room above the engine for fuel and exhaust plumbing. Make an excellent 'adventure' bike.

Edit, I am in no way condoning BMW.

[Frits Overmars]

Percived dissadvanges of the OP.
Height or width if you lay it sideways in a bike frame.
Joining the crankshafts.
It can be said two smaller crankshafts is no worse than a single bigger crank with a balance shaft.
Joining..... yes an issue. But if the engine is layed down across the frame with crankshafts pointng forward and aft, a gear set joining them ( four gears ) one being the clutch gear, two connected to the crankshafts and one extra as an idler (I'm sure I could find it a job also), gearbox behind that, CV joint, shaft down to a bevel gear at the rear wheel. Sort of a BMW ish. I've measured against my YZ 250, OP slighly narrower..

How about this Neil?
Only one crankshaft, so no need for a gear train to join two of 'm.
It's a boxer, so no need for a balance shaft.
It will be easy to separate the crankcase from the volumes 'under' the pistons.
You can have your shaft drive without the need for a bevel drive at the gearbox.
It will be a lot narrower than a BMW. In fact you could drop it right into a BMW frame for testing. And with the cultivated behavior of a TPI two-stroke it would make a great touring bike.

[Flettner]

Frits, sshhh, 😎 you are spoiling the surprise.