2t with 4t setup?


its quite simple actually. get some low octane gas, keep the intake valve. (or exhaust) keep a hole in the cylinder to serve as whatever valve you get rid of. specialize a camshaft. you still have the 2 stroke powerband. plus, you are being environmentally friendly (like i really care). that way, the 2 strokers will be left alone. so… i know there have to be holes all over this, but… what do you think?


With a question like that, who needs a computer virus? It’s just as good.


thank you for the “friendly” and “helpful” response.


what is this post about? Sounds like a reply to another post? “specialize a camshaft”


what do you think?
I think you have too much time on your hands! :wink:

Actually, I’m not sure what you’re trying to get at.


we can only be friendly and helpful when we know what you are talking about!


I’m with the others. I can’t make heads nor tails out of the post.

Can you be more clear?


Are you lost?




Well, since this is the same person who wanted to what would happen to his engine after it ingested Oxycontin (or as he referred to it, “Oxycotton”) pills, I don’t think that anyone should be too surprised.


Does oxycontin fix a bad head?

Sorry…couldn’t resist.


i was talking about a 2 stroke, with one valve, and regular gas. oil by the crank just like a 4 stroke, but with a 2t hole in the cylinder and with only 2 strokes.


It may have escaped your notice that two stroke engine design is somewhat different from four stroke engine design.
If the type of two stroke design with a cylinder port is what you are speculating about, then:-
Intake via a cylinder port requires feeding the fuel mixture into the crankcase. This is not a feasible conversion of the intake tract on any four stroke engine, and in any case would require an oil/fuel mixture for lubrication.
Outlet via a cylinder port requires a similarly unfeasible conversion of the exhaust routing.

You really don’t have any idea about two stroke engne design… Or four stroke engine design…

There is no ‘two stroke power band’. Like with a four stroke engine it is a function of many different factors in the design. A wider power band is achieved in many four stroke engines with multiple valves per cylinder, variable valve timing, etc.


I hate to tell you but this has already been invented. Detroit Diesel engines have exhaust valves in the head, intake ports at the bottom of the cylinders, and use a blower to do the scavenging.


you obviously did not read very carefully, i know exactly how a 2 and 4 stroke works, im just talking about making a 2 stroke with the whole 4 stroke setup. if there is a valve that lets the gas in, there is no need to fill the crankcase, which means that there in no required oil mixed with your gas, meaning that you fill your crankcase with oil just like a 4 stroke. meaning, that you will have something to blow out your cylinder port. an expansion chamber solves the problem of gas getting from the valve, and out the exhaust when the piston is at the bottom of its stroke. with no oil in the gas, and the same powerband as a 2 stroke (because it has only 1 valve and is able to have just 2 strokes). there you go, read carefully.


its quite simple actually.

No, its not.

get some low octane gas, keep the intake valve. (or exhaust) keep a hole in the cylinder to serve as whatever valve you get rid of.

You obviously don’t have any clue how much engineering goes into determining exhactly how large the ports should be in a 2 stroke engire, or where exactly they should be placed, nor do you have any idea about how the pistons and combustion chamber need to be designed for a two stroke application.

If you didn’t you wouldn’t think that it would be as simple as “putting a hole in the side of the engine block”

specialize a camshaft.

For what? Its a TWO STROKE.
TWO STROKE motors don’t use valves.

you still have the 2 stroke powerband.

No, you will have a 4 stroke motor with a hole in the side of the engine that doesn’t run.

plus, you are being environmentally friendly (like i really care).

In what way?
TWO Stroke engines spit raw unburned fuel and oil straight out into the atmosphere, polutting the air and the ground, lakes, rivers, water tables, and everything else.

that way, the 2 strokers will be left alone.

No one is bothering the 2 strokers.
They have already been limited to 50cc and smaller engine sizes, and for strict racing applications in motorcycles.
And chain saws.
No one really cares.

so… i know there have to be holes all over this, but… what do you think?

I think you need to go to the library, open up a couple of books that explain engine concepts and design for dummies, and start reading them.
Go to your local motorcycle shop and have them explain the items that don’t make sense to you (which, by the looks of it, is everything).

Go buy a couple of really cheap bikes that don’t run, and take apart the engines, and learn the differences first hand.



BTW a cylinder port is just another kind of valve…
SO you want just a cylinder port exhaust, and you think an ‘expansion chamber exhaust’ will take care of all scavenging issues. First off, an expansion chamber must be ‘tuned’ to a specific rev band. That’s why racing two strokes using expansion chambers have a VERY narrow power band, and LOTS of gear ratios… Secondly scavenging at the bottom of the cylinder requires forced induction to get the gas into the cylinder from the valve. That’s why induction via the crankcase is usually used, the piston compresses the fuel mixture in the crankcase on the down stroke (incidentally precipitating out the oil in the gas for lubrication).
Later racing two stroke design used two reed valves (‘two stroke’ has nothing to do with how many valves!), and a plenum to allow the fuel to self compress in the plenum for the required forced induction - at very high revs, using venturi effects, and resulting in a VERY narrow power band and only at high revs 10,000 to 12,000 RPM. Aso VERY poor fuel consumption.
You know almost nothing about how 2 or 4 stroke engines work, and ‘exactly’ in your claim is ridiculous.
You are right in one thing - there ARE holes all over your idea, and you obviously aren’t interested in what we think!


TJ i actually commend you for thinking outside the box. BUT… you need to get out of the small motorcycle engine mentality, and get some real gasoline engine theory. either by classroom work, or going to work at an automobile repair shop. (then go to school too)

sometimes what seems SO simple, upon further inspection is quite complicated. i guess this could apply to most anythign in life though. it is really RARE when someone stumbles upon something which is simple AND is practicle, and works. keep thinking, maybe one idea will hit. :slight_smile:


What could possibly be simpler than a two stroke engine? Well, try to make a better one and you quickly find out just how superficial that apparent simplicity is.
Hey! A violin is nothing but a wood box with four strings stretched across the top, so why are the good ones so expensive?


camshaft less stroke. exhaust valve does not keep but right. no 2 strokers can exhaust in intake. this is very simple. some holes are holes but nothing in.

Ok guys, I believe I just answered the question. It will be ok now.