wvarn1957

My Feedback: (3)

I just acquired a YS 61R that has never been run. No papers or instructions, but the only thing I lack at this point is the glow plug type and heat range. I'll probably run a 12 X 12 or 12 X 10 pattern prop on it using 20/20 fuel. Any plug recommendations would be appreciated.

Flyboy Dave

My Feedback: (21)

YS Engines .61R/AR

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Engine Type: 2-Stroke
Displacement: .610 cu. in.
Cylinders: 1
General Specs:
- 1 cylinder
- Displacement: .610 cubic inches
- Bore: .906 (in.)
- Stroke In: .945 (in.)
- Shaft: 8-1.5mm
- Low RPM: 2500
- High RPM: 18000
- Weight (no muffler): 19.93 oz.

Applications:
- Competition Airplanes
- Pattern/Aerobatics
- Competition

You can use any fuel/prop/plug combination you desire, but....

YS 20/20 fuel is really designed for the 4 strokes, it does not contain castor.
It won't turn much RPM with much over a 12-8 prop.
Any medium heat range plug will do, a K&B 1L, or a regular Fireball long would work fine.

FBD.

Enrique-F3A

I still have two of these engines. One is running fine on a Joker pattern plane (old pattern). I used OS # 8 glow plug. APC 14X6 prop , long header and Mac's tuned pipe, 15% nitro and 18% oil fuel. Regarding break-in remember that it is a two stroke ABC engine (ring less) so you must to break-in it at a rich setting but not too much as a ringed engine, it should not run cold, but a little hot to let the sleeve to expand in order to avoid excessive piston wear. Even after break-in, the AR should always run on the rich side. In order to save the bearings, try to run the engine for 30 seconds with no nitro fuel after each flying session.

Regards

wvarn1957

My Feedback: (3)

Thanks for the information, it is much appreciated. As far as the 20/20 fuel, I mix my own and use cool power oil with castor for all my glow engines.

Again, thanks for the information.

esamart

With 20% nitro you should decrease compression putting two head caskets or even three. I used APC 12x11 and 13x10 propellers which turned under 10000 RPM on ground with 10% nitro amd Hatpri 650 pipe. I dont remember lenght but had to use about 50mm extra tube between standard header. Exellent twostroke design with really fast spool up.

Regulator casket had too small holes and fibers frayed eventually which blocked fuel flow at least few first batches and then propeller and spinner departs dangerously without warning. Also remember reading from K-Factor that some had thick vaseline on rear bearing which took a lot of fuel to melt away until engine falsely seemed to be run-in.