hybrid two stroke motor.

[Nightbiker07]

ok, since 2 strokes are no longer used n the good ol US of A, i have a thought.

how about a 2 stroke where oil and fuel are not mixed?
HOW you ask?

Seal off the crankcase from the top end and fill it with oil.
Since the crankcase is used to pull fuel and air into the cylinder and would now be cut off, we need a way to get fuel and air into the cylinder.
This would be where a FUEL injector comes into play. injecting the fuel into a cylinder that creates no vacuum for itself.

now, we still have the AIR to get into the cylinder, and the answer is simple. use a supercharger type compressor to blow the air into the cylinder.

obviously, testing and tuning would need to be done to get the amount of air movement correct,but theoretically, this could work. if i posessed the machining and other skills needed, i would build one myself and sell it to honda.......but,i dont.

[200x newby]

how you gonna supply the wrist pin and connecting rod with oil?

[MTS]

Theres more holes in that theory than my Sunday socks, im not even gona start.

[Nightbiker07]

how you gonna supply the wrist pin and connecting rod with oil?

same way a 4 stroke gets oil to wrist pin and rod.......oil in the case, as i mentioned above.


yes, i know its not perfect. but these are the basic things that must be overcome, correct?

by all means, punch this thing to the ground. i would like to know where it would fail, as it is interesting to me.

[Nightbiker07]

Theres more holes in that theory than my Sunday socks, im not even gona start.

so, yes, please start. i really want to know what is wrong with the theory. what else needs done, what needs addressed, etc. etc.

[cr480r]

what else needs done, what needs addressed, etc. etc.

the port layouts and timing would need to be designed... exhaust tuning would be a nightmare at best.... a custom built cylinder... a supercharger and drive system... a draw through carb set-up would be more simple than injection... Ring seal: how would you keep the intake charge from blowing below the rings? a custom piston would be a must... Image the crankcase oil consumption/contamination problems if you didnt have a dedicated oil ring below the intake windows(and probably even still)... lower-end oiling issues: it would probably be easiest to convert a 4-stroke bottom end... electric start would be a must... and even if you got it to start and run I bet the output would be very weak... It seems to me that the boost would over power the return wave of the pipe and blow the intake charge straight through the cylinder and out the exhaust... not good... Its a neat idea, but certainly nothing new... Detroit diesels run on a similar concept but use an exhaust valve to keep the charge in the cylinder...

[MTS]

ok, since 2 strokes are no longer used n the good ol US of A, i have a thought.

how about a 2 stroke where oil and fuel are not mixed?
HOW you ask?

Seal off the crankcase from the top end and fill it with oil.
Since the crankcase is used to pull fuel and air into the cylinder and would now be cut off, we need a way to get fuel and air into the cylinder.
This would be where a FUEL injector comes into play. injecting the fuel into a cylinder that creates no vacuum for itself.

now, we still have the AIR to get into the cylinder, and the answer is simple. use a supercharger type compressor to blow the air into the cylinder.

obviously, testing and tuning would need to be done to get the amount of air movement correct,but theoretically, this could work. if i posessed the machining and other skills needed, i would build one myself and sell it to honda.......but,i dont.

Look at a polairs DFI system and tell me, You dont learn anything by me telling you. ;)

[Bigbore]

ok, since 2 strokes are no longer used n the good ol US of A, i have a thought.

how about a 2 stroke where oil and fuel are not mixed?
HOW you ask?

Seal off the crankcase from the top end and fill it with oil.
Since the crankcase is used to pull fuel and air into the cylinder and would now be cut off, we need a way to get fuel and air into the cylinder.
This would be where a FUEL injector comes into play. injecting the fuel into a cylinder that creates no vacuum for itself.

now, we still have the AIR to get into the cylinder, and the answer is simple. use a supercharger type compressor to blow the air into the cylinder.

obviously, testing and tuning would need to be done to get the amount of air movement correct,but theoretically, this could work. if i posessed the machining and other skills needed, i would build one myself and sell it to honda.......but,i dont.


Detroit Diesel... 3-71, 4-71, 6-,71 and up.

The plumbing and drive system for the supercharger, not to mention where is the supercharger coming from, the cam timing the intake and exhaust both have to be open at the same time on the downward stoke and both close at the 25% of the way up on the compression stoke. Spark isn't that hard but the CDI will need to run 1 : 1 with the crank. Loud to boot!

[ccdhowell]

Evenrude marine outboard engines work as you have described. They have a cool simulation video on their website, check it out.

[motoman110]

two strokes are like beating a dead horse...

[camatv1]

simple direct injection.. none of that crazy oil stuff. they run cleaner than some 4 strokes with out a catylitic

[300rman]

well, most of the problems listed here in this thread are problems you would run into designing a motor from the ground up.......imagine how the first guy to make an internal combustion engine overcame all the problems.....even then, old motors sucked. over time, improvements would arise, making it better and better......till the epa banned gasoline engines.

[cr480r]

two strokes are like beating a dead horse...

Then what does that make a 4-stroke?

[WLL]

i think the reason behin this is because money, two strokes are to easy and user friendly. the main reason people r in biz is to increas prof,and because two's use much less parts & labor costs to maintain it gives the avrage joe the abillity to pinch profits from the corprit co's. as evinrude has shown us fuel inj 2's are much more pleasing to the consumer and the enviroment than the high cost inaffishant 4's. i hope the 2's remain and progress as time goes by,but it isnt lookin good thanx corprit greed for making the rich richer and the working work harder:(

[Aka_am]

So fuel injection is cleaner then most 4-strokes? someone needs to reasearch this and come up with a viable plan of attack

[RedRider_AK]

Then what does that make a 4-stroke?

A horse whose bones have not yet turned into dust...

[BigGreenMachine]

I think its totally possible to build. We just need to put James9r9r in charge of building it.

[300rman]

I think its totally possible to build. We just need to put James9r9r in charge of building it.

from what i understand, detroit diesels on trains work in this manner. only difference would be less compression, spark plug, and, of course, slightly SMALLER size.