Hi Dave

A friend of mine is getting out of the hobby and has given me a NIB YS 61.S two stroke (rear exhaust) with a header and a tune pipe. I was wondering does the engine need to be sent over to Ys for servicing since it has been sitting in the box for god knows how long

also what kind of fuel am i suppose to use with this engine and in terms of power what engine is it comparable with.

Hi Dave

I was a bit wrong the engine reads 61 R Long stroke Two cycle.

Thanks Zain

About any 15 or 20 % nitro fuel will work. Pull the backplate off and check for rust. If none is present, go ahead and run it.

Hi Dave

Are parts still available for this engine, Also It turns at 18000rpm what kind of power are we talking about here. When did this engine stop being produced

Zain

18000? The engine was designed to run in the 10 to 12000 range. Prop accordingly or you will get to find out just how many parts we have.

Parts are still available.

Hi Dave

You are right, however i have a tuned pipe with it would that make any difference.

I also got the ys110 what a piece of craftsmen ship
in terms of power which one is more powerful.

zain

NO! The engine runs between 10 and 12000. Run it in that range.

Dave your help is much appreciated,

I have a pattern aircraft which recommends a 90 four stroke,or a 60 two stroke, several people have put the ys110 and are happy with this combo, would the 61r long 2 stroke be equally as powerful as the four stroke 110.

zain

No chance. The 110 will pull a 14x10 at 9500 rpm the 2 stroke 61 would have a tough time getting to 8000 with the same stick.

Hi Dave

I have the engine in my hand at this very moment. Another piece of beauty. There is no glow plug nor any prop size recommended. Any suggestions. Would you also know the BHP on this one.

Zain

About 1.7 hp, I guess. Try 12x9 or 11x10 APC prop. Shoot for a ground rpm of about 11000.

Thanks Dave

What glow plug should i be using.

Also would a ys63 fzs be over kill for a 5.5lbs pattern plane.
They recommend a 52size four stroke.

Zain

The 63 will be fine in your airplane. You can always throttle back

OS #8 should be good for your 61