Who makes and what size is the smallest 4 stroke in current production?

Here are the smallest 4 stroke engine: http://modellmotoren.homepage.t-online.de/

Jens Eirik

Ok it's tiny alright, but it's diesel. I wanted glow, mass production.

The smallest are the OS FS 30, Saito 30 and other engine marks of .30 class in mass production.. Former smallest was OS FS 20 and later FS 26..

I have an OS 26 FS, gummed up with castor from sitting for years but otherwise appears to be in good shape. I would like to find another, for a twin project that is in the distant future.

Oh and many thanks for the info Motorboy !!

Check Mecoa. They are making the old HP21VT which is as small as it gets with glow engines.

The old HP21VT from Mecoa are not very powerful and heavier than OS FS 20 but very quiet.

Not sure in mass production at Mecoa.. mainly after order..

Jens Eirik

I can whole-heartedly recommend the Saito 30. Runs like a charm. Besides it's so cute :-)

Saito 30 and 40 are now discontinued. .40 is an awesome little engine but gonna be hard to find.

I woudl suggest you keep an eye on the RCU marketplace and ebay to get a match to what you have already.

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Don't forget the HP VT.21 four-stroke owned/manufactured/sold by MECOA/RJL.

I wonder how many of us would be interested in small FS glow engines say 30 and smaller. It sure would be nice if we could get Saito or OS to bring them back to the market, at least for me it would be nice.

He didn't ask about power, he asked about size and the HP is a 21 and the same size as the OS20. It is unique in that it has a rotory valve induction. They fine running little engines and mecoa sells them.

There was no demand for small four cycle engines. That's why they all dropped them from their line up.

One thing no one mentioned is that the HP .21 that is currently sold has more power than the original due to some breathing improvements made by MECOA.

I have an OS 26 FS that i got with a bunch of stuff from an auction . It looks like new and i was pleasantly surprised when i put it on my test stand and ran it . I was going to use it as an "art object" , but since it runs so well , i am now looking for an airplane to put it in . Does anyone have any suggestions as to what would be a good candidate for this little gem ?

I have one in an old Pilot QB25L and it flies it beautifully.

Forgive my ignorance , but i'm kind of new to the plane world . Who made that plane , and do you have a link ?

Pilot made it and those kits are no longer available in the US. They will fly just about any 25 sized airplane.

Yeah , thanks . I tried a search for the plane you have it in and came up empty . I wasn't sure if the .26 FS would have enough poop for a .25 size 2 stroke plane . Would i have to run micro radio gear , or would standard size be ok as far as fitment and weight goes ?

The plane I fly originally had an OS25 FSR ABC in it. The FS 26 flies it just as well. I'm using standard equipment. 10x6 Zinger prop, 10% fuel.

Pilot hasn't been imported for years. Dollar to yen rate made them too expensive. We sold them at Hobby Shack and I bought many Pilot kits when I worked there. Still have several I haven't built.

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I bought two brand new OS FS-30 four-strokes a while back. Still have'em. The last time that I looked, they were still for sale at Tower Hobbies.

I ran and flew an OS FS-20 for over a year back in the early nineties. What a great running little engine it was. It was old and out of production when I bought it and flew it. The newer versions of the same engines have a reputation for being just as good running, but with more power. My FS-20 used to fly a Global Caprice .15 (high wing model, four channels) with ease and authority.

I bought the two FS-30s to power the Twinstar ARF. Now that I have a C-160 ARF, I shall put them in that model. I doubt that there will be much difference in power output between the older .26 and the newer .30.

My idea exactly, build a twin in the 40 to 60 range and power it with two 30 or smaller FS engines. The twins I have seen, and that ain't many, were vastly over powered. (I like scale flight, I'm not a hot dogger)

I have a friend that has a 20 lb CL-415 adequately powered by two Irvine 53's. It got off the water nicely it's first flight.

Smaller engines is the way to go for twins.

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Just look for a model that is rated to be powered with a .15 two-stroke.

There are a couple of Extra/CAP type models (ARFs) available from our Chinese friends. Also, there is an ARF model of a Cub that would fly well with that engine. It too is advertised as being powered by a .15 two-stroke.

Seems as though Ed Cregger had mentioned that Caprice also. Got any pictures?

I seen a slow poke with a os 26 in it it flew the plane well ,this was a older model maybe a 48 inch span .it was so quiet I thought it was dead or electric very sweeet combo.