I would like to find out which engine is more popular for a Great Planes Tracer.

Thanks, Flyer 202

I would go with the reliability of O.S...................[8D]

The reliabilty of the OS is undeniable but the YS , once set up correctly, is also fairly bulletproof and has gobs of power with a little less weight. I am not a YS guy as I have run the big OS 2 strokes the past 4 years in my larger planes. The one YS engine I have LOVED has been the 63 I have in my Oxalys50. Sweet combo!!!!!

I got the OS. It is strong, reliable and it has more power that it seems, I truly believe it is a lot more than a two.stroke 45.
But its HEAVY. You will probably have to move everything way back to get the proper CG. It is no longer in production, and the replacements are lot more expensive (56a = $299; 81a = $340).
So, I vote for the YS. It is lighter, cheaper and has more power.
Regards,

YS is best of these engines for aerobatics and 3D because of its highpressurised and regulated fuelsystem that allows you to locate fueltank near CG, no trim change during flight!
And YS has such throttle response those others cannot compete with

The YS looks like it is the most popular engine in this selection and it was the engine I was interested in before the thread started.
But now it is becoming clear that it is the lightest most powerful engine for the money.
Thanks,
Flyer 202

I had tracers with the Saito 72 and a 46 two stoke. Both had plenty of power. I find the Saito a lot easier to run and adjust than the YS.

Saito and OS are great sport engines. I own them, fly them with pleasure. The YS are competition engines, do everything the sport engines do, but with better power/weight. If you are thinking of getting into competition aerobatics, you really should check out the YS line.

I run an OS 160 2stroke in a 2x2 patternship no problems; VERY reliable but also HEAVY. I DO run my tank on the C of G - no problems.

I flew the Tracer with a Saito-72, and think it is the perfect engine for this plane. If you want a bit more power, go for the Saito-82! But IMHO, you don't need it for this plane.

Just make sure you have friends around who know how to adjust a YS if you get one. I have seem some very frustrated people looking at YS engines while I was flying my lines....!

I don't know about the Tracer but if I was going to pick one it would be one you didn't mention. I'd get the Saito .82. The YS is a good engine but to get all the power you need to run some high nitro fuel and the Saito .82 will give you what you want on 10% fuel.

I would strongly advise you use the 55AX, its absolutely reliable and a real torquer.

I'm with jeffk464. If you're not completely set on a 4-stroke then the AX .55 is a great choice. I have one in my Venus 40 and it is a great match (5lbs., 8.5ozs. less fuel). You can buy some nice servos or lots of fuel with the money saved. I'm running mine on Powermaster 5% and it runs great. So, you won't be needing to spend all that money on high nitro YS fuel. I mounted mine at about 10 o'clock to avoid dealing with inverted issues (which I seem to always have). It's not as streamlined, but it's simple to fuel, start and adjust.

David