I started out on the recommended CG and then moved it aft until when inverted it would fly hands off.

what is the cg range

thanks
38

Guys, are any of you running an onboard glow system on the inverted 2 strokes Is there a need for it?I've heard that they run better with than without. I would really like to run a 2 stroke mine, but not if I have to have the added wieght of an onboard glow system.

I used an MPI electronic on-board glow unit on my Matrix with an inverted 70 Surpass four stroke. This unit is pretty much fool-proof, and lightweight as well. But you have to "build" it and wire it. No big deal, just a bit tedious. If I ever have need for on-board glow again, I'll get another one of these.

However, unless you would rather not buy one, why not side-mount your engine and use a Pitts muffler? The ST cowl is perfect for this. A regular "can" muffler sticking out the lower side of the cowl would look funky, cause lateral balance issues, and probably need a very long cut in the cowl for clearance (or else the muffler would need a spacer). The ST cowl is boxy, and rather wide at the bottom.

A side-mount on this airplane (with a Pitts muffler) is very neat and clean. The cowl cheek covers much of the jug; just the head pokes out on my OS 1.08, and that's a good-sized engine.

Anyway, while this might be more info than you wanted, consider a side mount. There are two drawbacks to this; you'll have to knock out the firewall blind nuts, plug those holes, re-locate and drill new ones for the engine mount.

Second, you'll have to get creative with the throttle linkage if you choose to utilize the stock throttle servo location. I used a bell crank.

Yes, all of this is a bit of extra work; but well worth it, IMO.

Thanks Steve, I was worried about the head sticking way out the side. Sounds like this may be the way to go. I'm thinking about the O.S. 120 ax.

OK... after 7 month's in the box, I started working on the S.T...... But............
For those that have not noticed the elevator "whatever" problem... Have you done
anything different in your build??? Check and corrected incidence??
I've just hinged mine so far... So tips will be really great:-)....
I'll be useing YS-110/pitts and HS 5645"s on 6v's and tail servo for the rudder....

I built it by the manual with no elevator problems. You will like the YS 110 on this plane. I'm using a 2100 mah Lipo with MPI switch and regulator, the battery was mounted aft of the gear block. Rudder servo was a 5955TG and the rest were 5945MG.

Well I think I finally decided on the Saito 125 for the motor, but I have a few questions. Was any modification needed to mount the motor? I know it is larger than the 100, so was just curious on what, if anything, needed to be done to mount the motor. Also, what prop would ya'll recommend? Thanks for the help.

Does anyone know the formula to determine static thrust?

From looking at the advertisement photos, it would appear that the muffler, when mounted in the "Pitts position", is wider than the bottom of the cowl. Dunno for sure without a measurement; but I'd check that before I bought the engine.

I plan on maidening mine this evening if all goes as planned. Here’s my setup:

Saito 1.25
APC 16x6
Hitec 5625’s Elevator and Aileron
Hitec 5945 Rudder
Standard on throttle
TBM 2800 Li-Ion & reg.

I’m not sure of the weight but it feels light.. [:-] It balanced out perfectly with the rudder servo in the tail. I broke in the Saito last night and so far I’m very impressed. It was by far the easiest Saito break-in I’ve done. After about a half a gallon I’ve got a rock solid 1800RPM idle and it’s turning the APC 16x6 at 9000RPM on 15% Wildcat (still very rich). After I burn up this gallon I’ll move up to 30% nitro. I’m hoping to see the RPM’s in the mid to upper 9k range. We'll see!

finished my ST and it looks like new
i'm going to fky it sat and sun


38

I'll post up a more complete when I have more time. In the mean time, my initial impression: BAD *****!!!!!!!!! [sm=thumbup.gif][sm=biggrin.gif]

Parachutes, harriers, elevators and rolling harriers are incredible! It will do a wall to ceiling with absolutely no tendency to snap. In fact, I could not make it snap with too much elevator at any attitude or speed. It will, however, snap with too much rudder at the wrong time but only on my 'all-I-can-get-on-every-surface-rate'. It's the best glow-powered plane I've own or flown. I'm in love!

Anyone?

blk96gt...
The 100 and the 125 share the same bolt pattern so it will physically bolt up to the mount just fine. I think the 125 is 1/2" longer or so. You may have to adjust the cowl a bit. But, it will fit the Showtime just fine and you'll love the extra horsepower. The 125 is a much better fit performance wise than the 100. A APC 16x6 or 17x4W is the prop. Mine pulls the 17x4W a little bit better.

Thanks
Barry

Would any kind soul help me measure the box of the showtime? Because it is oversized item and the freight company for shipping charges by volumetric weight if it weighs more than the actual thing. I am interested to bring into Singapore(There's no H9 dealer here, so the only way is to ship it in)....
I dropped horizonhobby an email regarding this, but haven got a word from them since last week....

mathinstrument.... 54&1/2"x 19&1/4"x7&1/2"

Thanks raideron for the dimensions! I have calculated and the rate's still reasonable! Looks like my showtime will be on it's way!!!!

Excellent, just what I wanted to know. I can't wait to get this thing in the air.

Yeah dont be like me and measure out the engine distance from the intructions. The 125 is longer which caused all kinds of havoc when i used the intructions distance.

I use an Onboard glow system on my 2 stroke on my Showtime.. but I didn;t mount inverted.. I just put it upright like a trainer.. Honestly I like the look of the big cyclinder out the top of the cowl. Just my preference but the engine runs great upright.. even better withonboard glow.. never deadsticked it and it flies beautifully. Besides, it's not a scale plane... so no need for a scale engine right.

Hi guys,

I'm breaking in my YS-110 and hopefully the model will be maidened next weekend. I have a question on the CG location, since I use a lighter engine such as the 110 I decided to go for a push pull system. Despite that the model comes nose heavy at the recommended CG location, I also moved the LiIon pack as rear as possible but it's still nose heavy. Have you encountered a similar situation? People in this thread recommended to go for a push pull with lighter engines but from my experience this seems to be wrong.

I will probably fly it the way it is and if I don't like it I will install the servo at the tail.

Nick

This one strong airplane. I maidened yesterday, I was having so much fun that I forgot about the time and ran out of fuel. It struck a tree and fell about 25 feet to the ground. Expecting to find a pile of rubble, you can imagine my surprise and delight when I found it sitting on the ground on its feet with a smashed cowl and broken motor mount completely intact with just a couple of bumps and bruises.

your YS110 probably weighs about the same as my TT 120 2 Stroke about 32 Oz with muffler. I believe the YS110 is about the same at
about 29 Oz with muffler. I opted for the Push Pull system with Servo mounted in the Tail and have the battery.. 5 Cell NiMh at the the back of the compartment. Cg right on reccomended. Flies nice that way.. although most of the guys that fly 3d in the club say CG should be moved back beyond reccomended but I like it there so you should have no issues putting the servo in the tail.

I have the saito 125 in mine and I had to move the servo in the fuse for the pull pull. Probally didn't help because i moved the fuel tank as close as the wing tube as i could. The reciever and the 4/5C 5 cell battery is just behind the tube.