"1 Stroke" INNengine REX-B 1S-125cc

[Paul De Tourtoulon]

 

[Paul De Tourtoulon]

For some reason, once the link was in I couldn't put any text to it and that dammed publicity band came up, so that's why I have this second post !.

So who has heard of it ?, I watched a couple of videos, but I couldn't see the valve system.

 

Edited August 9, 2023 by Paul De Tourtoulon
ed picture

[Don Fry]

I think, the motor has 4 cylinders, RCV style ( sleeve valve ), with the cam track controlling the ins and outs of pistons and gases. I assume the square bit on the back is the carb. Very clever, or too clever by half. Sleeve valves have a chequered history. 

[J D 8]

I have seen the video, the term "one stroke" is a misleading to say the least. The engine is a wobble drive or more correctly a swashplate drive with pistons that lay along the side of the drive shaft.

        Nothing new here, this type of engine first appeared in the early 20th century.

         There is even a model version that was available at one time called the Aero 35.

[brokenenglish]

TBH, I'd rather have my ED Bees.

[J D 8]

               Just to add to the above a one stroke engine has a piston head each side of the swashplate so there is a firing each time the double headed piston moves.

  The only true one stroke engine is a gun.

[Paul De Tourtoulon]

The word 'one stroke' was chosen as most people associated 2 strokes as moto bike engines with an oil mix, it's in one of the videos.

 

Ps still getting lots of pop up publicity !.

Edited August 10, 2023 by Paul De Tourtoulon
unwanted publicity.

[J D 8]

      The system does make for a very compact unit and likely benefits from modern metals/materials in its construction which were often what let down early versions.

[Brian Cooper]

Is the carburettor made by Lego.... 

[Jon H]

I cant decide if i dislike the music track more or less than the sound of the engine. 

 

Interesting idea, but as has already been mentioned its an old concept and like the wankel rotary, its been done before and not ended up a massive success. 

[Nigel R]

I nominate Napier Deltic for having done the compact opposed piston thing, very successfully, a fair long time ago. Although that did not weigh 35kg.

[Jon H]

1 hour ago, Nigel R said:

I nominate Napier Deltic for having done the compact opposed piston thing, very successfully, a fair long time ago. Although that did not weigh 35kg.

 

I think a number of diesel engines use opposing pistons. If memory serves the cranks are slightly out of phase to give the required port timing. 

[Simon Chaddock]

No mention of exhaust emissions.

Oil in fuel 2 strokes, which is what it is, are noted for incomplete combustion and limited scavenging let alone any unburnt oil in the exhaust.

[kc]

The Deltic is a 2 stroke diesel with 36 pistons but only 18 cylinders with  ports in the cyl liners.   Configured as a triangle - somewhat like 3 Vee 12's fixed together head to head with the three crankcases geared together.  Or the smaller 18 cyl version like 3 Vee 6's.   Alloy cylinder blocks too.   Used in railway engines and in ships as generator engines.  See Wikipedia for an animated view of how this engine works.  Deltic was developed from a Jumo diesel aircraft engine.

 

I think the Deltic con rods were different lengths to produce a scavenging effect.   People in the Colchester factory could be heard talking about " exhaust con-rods" which seemed odd to someone who knew  a bit about ordinary engines but little about Deltics!

 

1960's Commer lorries also had opposed cyl engines which made a very distinctive 'knocking' noise.

 

None of these weird engine layouts seem to last -eventually everything reverts to an ordinary layout.

[kc]

Deltic info is here

Anyone interested in engines should try to visit the Internal Fire Museum of Power in west Wales between Cardigan and Aberaeron.   Allow lots of time & leave your wife on the nearby coast!

If you want to see inside a sleeve valve engine there is one cutaway at Old Warden.  

[Frank Skilbeck]

1 hour ago, Simon Chaddock said:

No mention of exhaust emissions.

Oil in fuel 2 strokes, which is what it is, are noted for incomplete combustion and limited scavenging let alone any unburnt oil in the exhaust.

Only if the crankcase is used to charge the cylinder, modern fuel injection also stops unburnt fuel escaping in the exhaust. These engines are usually fed by a supercharger/turbo so the crank is lubricated just like a 4 stroke.

[Simon Chaddock]

Surely if the crankcase is used to charge the cylinders then lubricating oil will pass into the cylinder.

In a 4 stroke the crankcase and cams are sealed from the combustion chamber so no oil, or virtually none, gets into the combustion process.

[Frank Skilbeck]

2 hours ago, Simon Chaddock said:

Surely if the crankcase is used to charge the cylinders then lubricating oil will pass into the cylinder.

In a 4 stroke the crankcase and cams are sealed from the combustion chamber so no oil, or virtually none, gets into the combustion process.

Yes, but these engines use an alternative charge method so no air/fuel passes through the crankcase. The one stroke state that exhaust velocity is such that in creates a partial vacuum in the cylinder which draws in fresh charge, theres a review of it Here

 

Back in the seventies, before Norton Villiers went bust they were working on a stepped piston twin cylinder two stroke, look up Wulf engine, with modern fuel injection it would have been very clean.Frank

 

At university one of our engine test bays had an opposed piston two stroke tank engine which used a combination of turbo and mechanical supercharger to feed the engine.

[Nigel R]

14 hours ago, kc said:

I think the Deltic con rods were different lengths to produce a scavenging effect. 

 

in each pair of pistons, one was slightly "ahead" of the other; one of the pistons controlled the exhaust valves, the other controlled the inlet. (I think).

 

at 4:21 in this video

 

 

[Nigel R]

15 hours ago, Simon Chaddock said:

No mention of exhaust emissions.

Oil in fuel 2 strokes, which is what it is, are noted for incomplete combustion and limited scavenging let alone any unburnt oil in the exhaust

 

Deltic was supercharged; inlet went straight to combustion chamber. I expect it is probably outclassed in terms of emissions by modern 4 stroke diesels of course, but the Deltic was from a time long before direct cylinder injection and the fine control that current ECUs provide, but there was no oil in the chambers.

[Outrunner]

43 minutes ago, Nigel R said:

 

Deltic was supercharged; inlet went straight to combustion chamber. I expect it is probably outclassed in terms of emissions by modern 4 stroke diesels of course, but the Deltic was from a time long before direct cylinder injection and the fine control that current ECUs provide, but there was no oil in the chambers.

I think the Deltic definitely would not pass any emission regulations, have you seen the clouds of smoke emitted by Deltic and other diesels of that generation when they start up!

Fantastic sound though!

[Simon Chaddock]

Deltic emissions? 😉

https://www.youtube.com/watch?v=hvG-d9RkFtk

Piston ring oil blow by was always a problem with the Deltic. The blue smoke did reduce as the rings bedded in but got worse again as the service overhaul approached.

[Nigel R]

Anyway.

 

Back to the OP.

 

This engine, it has 4 pistons, who cares if 2 or 4 stroke. I see nothing but convention going on with the business end of the piston. Whilst they're squashed into a tiny volume, they are regular pistons. Air cooling might be problematic with the low volume? Liquid cooled, I guess no real difference to a conventional layout.

 

The conrods have a 'device' to get linear motion translated into rotary motion. That part looks like a disaster waiting to happen... I'm guessing tolerance and wear will make operational lifespan of this unit really very low.

 

I just can't see the genuine advantage over (say) a regular radial or flat layout. Maybe I'm missing something. Or maybe not. After all, Mazda have been making Wankel rotaries for years and they haven't really caught on.

 

Also, I call shenanigans on their power output vs displacement claims. Their claim of "1 stroke" isn't precisely confidence inspiring when it comes to veracity of their media output.

Edited August 11, 2023 by Nigel R