I'm gonna get a mojo but don;t know what engine or servos to get. Should I get a O.S. .55 AX, Saito .72, or Satio .82. What prop? And what futaba servos should i get. are standard digital or hi-torque.

thanks in advanced
da johnny boy

I would use the saito .82 with a 15X4 APC prop with digital servos. and a 6volt batt.

Is this your first 3D profile?

2-strokes are easier if you're learning to hover -- they torque less than a 4-stroke. They're also easier/cheaper to fix if/when the inevitable happens (don't ask how I know this) :-)

I've got profiles with TT46Pros in them and a couple with Saitos (82 and 100). Once you've mastered the basics, the 4-strokers provide a few benefits but also require a little more skill to take full advantage of -- they're quite sensitive to small throttle movements when hovering or harriering.

Another thing to consider is that the Mojo is a very light aircraft and some folks have had problems with vibration when running big 4-strokes, although I believe the 72 is somewhat less shakey than the 82 or 100 -- but the 82 puts out quite a bit more power (I'm told) so I wouldn't bother with its smaller brother.

You might also want to look at things like the cost of props. An 82 needs a 14x4W or 15x4W (depending on how much nitro you run) and they cost quite a bit more than the 12x4 you'd run on the 2-stroke. If you plan to bust a few props then you'll have to add that cost to your flying bill. I went through a lot of 12x4 props when I was learning to 3D but haven't broken one now for nearly a year.

As for servos -- on a 40-sized Mojo you can get away with standards (S300? or HS425/475) quite easily.

Faster, stronger servos are good -- but you probably won't notice the difference if you're just starting (although you will later). I fly HS5925s on my tail. These are digital, metal-geared and *fast*, real *fast*. On the wings I use Futaba S3010 servos, these are non-digital, nylon-geared and also reasonably fast and strong but I don't like them much because they're too sloppy. With the throws you'll be running for good 3D, even a half a degree of movement or 1/32" of bearing slop in a servo produces a *lot* of unwanted slop in the control surface.

Tell us more about your experience, abilities and budget so we can help more.

i probaly can't pay more that 50 per servo at the most, the cheeper the better. I have done some hovering on my ultra stick but nothing else. I probaly can learn 3d fast so i want a plane that could last through out learning and advanced 3d.

PM in your box about two NIB sets of new digitals to choose from .

what are the least expensive digital servos i can get that are resonably fast and strong.

I have a Mojo with std servos and an OS 50. I also have a Burrito , same servos, YS 63. I like YS63, Saito 82 , OS 50 or 55 in that order for these planes. Any of these will do the job.

da johnny boy,
If that is the case, the JR DS-811'S should work perfectly for you.

If you can only afford 1 strong servo put it on the rudder. Next priority is elevator. Consider using a 5 RX cell pack that gives more power and servo speed for a very small cost.

I fly a similar sized model and LOVE my West 50 T1 plus the matching throttle pipe turning an APC 13x4 wide. IMHO the BEST 50 size 3D 2stroke set up. However it is going to be expensive in the US.


If you go the Saito 82 route in a 40 size profile then you MUST reinforce the wing to fuz join with glasscloth and add braces to the tail. The vibration these engine produce is ferocious and will literally cause models to self destruct in the air. [How do I know ?]

You MUST glass the wing joint and brace the tail? I have 4 of these light profiles. A Mojo60, 5.2 lbs, 1000 sq inches, flying for 6 mos with a Saito 91 with no glass and no braces. My Mojo 40 tail didn't break when it crashed hard enough to break a wing. My Burrito tail survive a crash that powdered the wing. I have found no tendency for 4 stroke vibes hurting anything on a Mojo of any size. They may not be pretty to some folks but they are for sure tough.

I'm with Jack on that one.

I've got a couple of profiles with Saitos in them and they've stood up just fine to the rather incredible shaking they get.

The Mojo is so strong it'll withstand being lawn-darted straight in from over 200 feet -- yes, I've done it :-) All it needed was a little balsa and film where the battery came through the leading edge of the wing. absolutely zero other damage. Try that with a Katana 46 or Katana 70 :-)

If the poster's planes are breaking up then he's buynig/flying the wrong designs :-)