rhysdejager

any one seen this before??
whats it like??

twomanytoys

Its not in the states yet. Its just a prototype that was seen at a few shows.

JB COMP

yeah, I've seen picture before. but I heard it will not work.

I'm sure supertib will post something on it.

twomanytoys

And why would it not work? It would work just fine. Just like twin 2 strokes in atv's. No reason why it would not work. I know Supertib is a real smart guy when it comes to this stuff but he is wrong on this one.

jkdv8

My Feedback: (1)

shouldnt the carb be bigger. i mean you cant put a smaller carb on a big engine. i.e. a .15 carb on a .30, although that would be sweet if it does work.

JB COMP

I would have to go with what supertib said in a different thread about this engine.

twomanytoys

And what is that? Did you ever hear of a banshee? Same thing. Its a v twin 2 stroke that puts out massive power.

rckal

I believe the problem would be something to to with the exhaustports / and how it/they would affect a 2 stoke engine, and the mechanics of it all.

Well it goes something likt that

Generalx5

I dont think so, 2 ports cant affect engine performance, who ever said that would make the engine inoperable, I bet you that engine could run even without a muffler on. BTW, thats a kyosho engine right? Dam, 1 engine is hard enough to break in and now they doing2.....thats like 2 times harder to break in, no not really. Bottom line: whats the cost for one of those?

The Winner

it is not a kyosho engine! is a sirio engine(italian mill) while kyoshoe engines are chinese mills! just kyosho is distributor of sirio! i think now kyosho work with orion engines! but in the american site have the sirio engines! anyway i think that this crazy brand(sirio) will make this thing to fire up in the future! and the break in is the same in a single cylinder engine and at a single cylinder! kyosho gxr28 bmw3 this is not to engines so it need double break-in is the same engine but with two cylinders! the carb is ok! because this engine is 21! here the main distributor of kyosho ine greece said that he ask sirio and said that each cylinder is .10,5 cu in! so 2x10,5=21!

rhysdejager

thanks everyone
guess it will be a while before i have one of these in my car
oh well

cheers everyone

downunder

Very neat and it'll certainly work but not all that efficiently because it seems to be around a 60 degree V so the crankshaft port timing can't be ideal for both cylinders so it has to be a compromise, most likely timed as though there was a single cylinder set between the two. I'd suspect though that the port stays open much longer than usual. The transfer ports may have some unusal timing too because of the way two pistons are compressing the mixture in the crankcase at different rates. One small advantage though would be that now there are two pistons compressing into the crankcase with a volume not much larger than if it had a single cylinder.

pur3evil

The 2-stroke V-twins in the Banshees and snowmobiles, etc. all use two seperate carbs to feed the two cylinders (some are even fuel injected). The carbs feed directly into each cylinder. The crankcase is not used like it is in RC Nitro engines.



I don't know all of the physics behind it, but I'm with supertib on this one. I don't think the V-twin nitro will work, and if it does, it'll likely run quite poorly.

-Howard

NitroBobby

this is all speculation. are any of you guys mechanical engineers? any advanced degrees in any subject that would give you credibility with these answers?

you guys sound like the donkey from whinnie the pooh "it'll never work". screw that. if there is a will, there is a way. it may cost a bunch of money, and it might not be efficient at first, but i think that if you put enough effort into it you can get it to work. it's an engine. it's not anything new. humans have been messing with internal combustion engines for a century now and we've overcome many more difficult issues than this. i don't think that getting a v-twin diesel to work is that hard of a feat to overcome.

86waterpumper

It will work fine if the carb is the proper size. Banshees did come from the factory with two carbs, but the best invention for them ever is the dynoport 2 into 1 intake kit with a single lectron carb. There is no rule that says you have to have a certain number of carbs for every cylinder. The old xr dirtbikes had two carbs for one cylinder etc.

twomanytoys

Thats exactly my point because I used to have a Banshee with the single carb mod so thats why I am saying it will work and supertib is wrong on this.

downunder

There's no comparison between this Banshee engine and the Sirio car engine. The Banshee is a split crankcase so each cylinder has it's own compression volume like a single cylinder engine. The Sirio is a crankshaft induction like a normal single cylinder engine (exept one port is trying to serve two cylinders with different piston positions) while the Banshee has individual reed valve induction like the little Cox .049 engines.

hrdcoreglf

If it works or not doesn't matter, it would not fit in my buggy, and the extra weight would cost the race. Thats only an 1/8 scale buggies opinion.

SManMTB

It looks cool!

46u

My Feedback: (3)

Banshees are not a V twin but a side by side twin! All so I am sure the crankcase are separate from each other. We are talking about two TOTAL different designs!

donkey doctor

Hello; Downunder has it sussed; A two stroke relies on the underside of the piston to move the nixture from the crankcase to the combustion chamber. In this engine there are two pistons but only one crankcase. To time the induction of the mixture into the combustion chamber, the first cylinder gets the pressure and the bulk of the fuel charge leaving very little for the second cylinder. Those high performance v twin two strokes had separate crank throws for each cylinder, and the crankcase was sealed so that piston moving down would compress the mixture into the combustion chamber, the only way that would work.

An interesting discussion starter, but if it did work, someone would have done it years ago.

rccheech

the only way this engine would work, is if both cylinders were to fire at the same time, having such a small carb the volume of air/fuel mixture would starve the engine and probaly not rev consistantl and blow up, not to mention the mad vibrations caused by the cylinders firing at the same time... waste of time and engineering if u ask me.

SManMTB

I like all the armchair engineers in here.

supertib

this motor wont run and you don't need to be an engineer to see that..... having 2 differently timed pistons sharing a common crankcase would end up making a dam bomb.......... I have been running Snowmobiles for years and have blown many crank seals on my engines..multi cylinder 2 strokes don't






like sharing the crankcase.. they go bang very fast when a crank seal lets go.......

the only way this sirio could operate on the same crankcase volume is if both pistons hit TDC and BDC at the same time... they have rotary 5 cylinder 2 strokes for aircraft, but each piston has its own crankshaft working off a common central crank, and all 5 pistons fire at the exact same time... so even though it has 5 cylinders it fires as just a big single..........

the only way to make multi cylinder 2 strokes work is if you can isolate each cylinders crankcase, or if you fire each piston at the exact same time. there is no other way around this..........

This Sirio is just a model to attract attention, the model at the show only has 1 piston in it and the other side is wide open.... why on Earth would Sirio spend millions developing a motor that wont fit into any commercially available RC's...look how wide the block is and tell me where that would fit.... So really can you see Sirio developing a motor for a non existent market....or is this a nice little model for the toy show made to attract attention....


StManB why dont you load this into MODA and see if a multi cylinder 2 stroke can run like this..both piston sharing the same crankpin and crankcase volume...

SManMTB

No one here know how it looks inside, that's pretty much all I said.

I think it would run but probably not great, but I really don't know.