In my case, I changed the control horn hardwares, hinges, landing gear, and all three wheels; reinforce the landing gear mount, and wing center section. Otherwise, everything else are stock including the engine mount. I am using YS 110, so the fuel tank is placed at CG location. The servos are Hitec 9245's for all control surfaces, and HS55 for throttle.

Good luck,

Kevin

Hi Super D There are a ton of threads on this airframe. Tommy S. Has been most helpful as he has built and flown it with good success. All of those guys have been helpful in answering questions you may have.

The ARF comes with metal hinges that bind. I called Global and they sent me some Dubro's. I have not flown mine yet but April is the set date. I went with YS 110. The saito is a great choice. The instructions suggest going with a stronger mount if you are up in the 120 range. I went with a Dave Brown which seemed to be the same as the one given with the plane. I beefed up around the existing mounts behined the firewall as suggested with slow epoxy.

They suggest wood screws to hold the mount to approx. 3/8 hardwood beams. I went with T-nuts. There is ample room to get them in with needle nose pliers. The crimps for the pull-pull seem to be aluminum. I cut my own (larger) so that I could double back with the cable through the crimp tube and used heat shrink on all of them. I didn't like the control horns. I used them on the ruder and elevators but went with dubro 4-40s on the ailerons. When you read the threads you'll see a lot of info on the extended heavy duty dubro links used by a lot of guys to get the link center point over the hinge point.

The plane comes with very good instructions, the best I've seen in a long time. I don't fly 3-D but do fly pattern. The control throws given for normal pattern in the instructions are way too much according to about five guys who answered me when I asked about them.

These are just my observations and what mods I made when I built the plane..Good luck Pete P.

That's a good question and I'm sure there will be a lot of good suggestions.

I won't go into servos. As far as everything else, here's my $.02:

Toss the original gear and get some aftermarket gear. I have Graphtech gear on mine. Also, I would remove and rebuild the landing gear plate so you can get in and beef up that area. Unless you fly off a nice smooth surface you'll find a divot in an otherwise wonderful field and the gear will come off even if you reach in and put some triangle stock in to reinforce the LG plate (ask me how I know that). Mine now has a piece of 1/4" aircraft ply from the firewall to the former that the wing dowels go into. I know its overkill, but I won't be coming home with my gear in my field box unless the unthinkable happens.

I used standard CA hinges I had laying around but had to replace the hinges in the tail after a few months (and a lot of flights) so I would suggest just buying the Radio South hinges and be done with it.

I have a YS 1.20 FZ in mine because that's what I had on the shelf and am using the mount that came with the plane with only one issue and this is after a full season on the plane. The screws that hold the mount into the wood are not holding tight and I just replaced them with brass threaded inserts and machine screws. Other than that the mount is exhibiting no ill effects of the FZ being bolted to it.

After a couple months I put a Dubro tail wheel assembly on mine.

As I stated in an earlier post, I'd knock the counter-balances off the elevator and rudder unless you plan on doing 3d with it as well.

Those would be my suggetions.....

The airplane would probably be OK with the hardware that comes with it. Most of the changes
I made were just personal preferences from past experiences for things I like better. The
only modification you MUST do is the landing gear mount, it WILL fail if you do nothing. I first
put triangle braces in mine but later had to do additional bracing, so save yourself the future trouble
and time and do it while you are assembling it.

tommy s

O.k., I'll do you a solid...here are the notes I made for myself (taken from different replys in this thread...).
I chose to use the Chip Hyde aluminum anodized control horns(Central Hobbies). I chose to replace the pull-pull on the elevators in favor of the D.E.P.S system from Central Hobbies. I have the Icepoint canopy (looks good). I will also use the Hyde Type A mount. I am still debating on the Hatori #725 and 726 muffler/header combo (don't think its necessary but it sure looks cool). Oh, and lets not forget the ys110...

Progress report:

I flew last Thursday after getting the Iron Bay regular installed. This one did not leak, by the way, Archie sent me a replacement for the one I had that leaked slightly. This one is ok.

I mounted all, removed the tank and rechecked all internal plumbing, put it together and added an extra refuel tube with a 'dot'. I then put all back together and headed out to the field.

Disappointing day. I set the needle valve to about 2 turns and the engine started right up.. the regulator stopped the annoying excess fuel. It actually started on the third flip with the engine inverted (plane on the bench right side up). I ran it for a few seconds to warm it up and went to full throttle in gradual movements. Ok.

Next, I went to idle and tried fast transition to full. It tended to die. I got it to full throttle and did the fuel-line pinch test. The engine immediately died. To lean. So, I restarted and went to full. I opened up the needle valve about a half turn.. pinch test, almost died. Went to idle, added another half turn, went to full. This time, it went right to full throttle.. improvement, but when pinch test, it tried to die again. I went to idle, added another half turn..... well, this continued on for a while until I was about 6 or 7 full turns out from completely closed, and still no increase in RPM when the fuel supply was pinched. But, it did not die either.

I put it in the air to see how it would perform, knowing that it was running a tad lean. I did several orbits then tried a few maneuvers. When going vertical, though, the engine died. Dead stick landing.

I tried to play with the needle again, but no dice. I got it to the point where the needle just about fell in my hands, still to lean, not enough fuel pressure from the muffler to allow enough fuel to flow.

Here's where I believe I reached catch 22. I removed the regulator and reset the needle, tried to make things go but every time I got it running where I thought it would be ok, I walked it out to the flight line, walked back to the pilot stand, hit the throttle, the engine died, or it would die before I even got to the pilots stand. Same as before the regulator. I believe I need crankcase pressure, however, I also believe that the carb on that Evolution is crap. If I add pressure from the crankcase with the regulator, it's the same carb and it will behave as before without the regulator on muffler pressure... still die on take off or on the flight line, or during or just after vertical.

Solution: I ordered an OS 1.20 AX from Tower. It will be here tomorrow. This is the engine I should have used in the first place rather than all this frustration for the past few months trying to get the Evolution 100 to run. So, my recommendations is that the Evolution 100 is not for this type of flying. I must say that when it does run right, it has lots of reserve power, but it's getting it up there so I can use it is the problem.

One thing I like about the OS 1.20 AX is the RPM range. Peak power is at around 9,000 rpm and will turn a large prop. So, this should work out as a quiet powerhouse for my Excelleron. Now if the weather cooperates, and I can fly this weekend (does not look good for us up here in the Northeast, well, New Jersey that is), I will report on how satisfied I am with this engine plane combination (how's that for optimism!!)

The reasons I did not get the YS-110 are:
1. availability. LHS said several months wait for one.
2. Complex. I am a relatively newbe at Pattern and don't need the complexity of such an engine, although I understand they are quite the power house and reliable. But, tough to beat the reliability of the good old standard OS's.
3. as I said, adequate power at low RPM.
4. Cost. The difference was a lot so I opted for the OS over the YS-110 for cost reasons in addition to my other reasons. Hope that makes sense to you pro's. Tower had a pretty good sale deal going $20 bucks off and free shipping, so tough to beat.

DS.

I did not reinforce my LG mount. What I did was to brush in about an ounce of slow cure epoxy into the plate and mounting area. With everything actually glued together, it seems to be fine and is holding up well, even on less that perfect landings. I like this model.
Gordie

Gordie: Do you fly on grass or pavement?

Dick.

Hi,
I expect a report on the 120 AX, please.
Good Luck,
Dean Pappas

Hi Dean! haha.. yep.. will do. It seems that Bob S, Rick W, and I all are either waiting for one or have one and are foaming at the mouth to fly with it. I am so disgusted with the Evo 100 I could throw it somewhere. I was at Straw last Thursday and got so disgusted that I was going to remove the engine right there and toss it in the woods... but I didn't. Eventually, I will yank the carb off and get that one from Ron and make it work that-a-way. Just want to fly, ya know what I mean?

But, first, as everyone has said, a good healthy bench workout for the engine before putting it on the Excelleron.

Dick.

CGRetired, will you use a fuel pump in your 120AX and if yes, which one ?
Also, the 120AX from Tower has a remote needle or it is the model with the needle on the carb?
I also want to buy an Excelleron kit and thinking to use the 120AX although I have a YS110 available. That is because of the fuel cost and complexity of the YS.

As of now, I am not planning on using a pump. A friend just ran one in yesterday (meaning he spent some time on the bench running it for a few tanks) and it had no problems with fuel flow. My fuel tank is right behind the firewall so I don't have a lot of distance for fuel to flow, so muffler pressure ought to be satisfactory.

Regarding the engine of choice, if you had been reading previous notes in this thread, I had been having serious problems with the Evolution 100 I was planning on using on the Excelleron. Well, I am in the process of using the OS 1.20 AX and will have more info as I move forward with this installation and operation.

From what I read, though, you can't go wrong with the YS-110. I sort of wish I had decided to get that instead of paying the money out for the Evo and now again for the OS. I could have bought a YS-110 for what I've spent on the other two. But, we will see how the OS 1.20 AX performs.. and very soon if the weather gives me a break.

DS.

Thank you for your prompt answer CGRetired.
Waiting to see your report of the 120 AX.
I also want to salute Dean.
Is there a way of getting a copy of your Excelleron review in the MA magazine ?

Oh man.. I accidentally threw away my copy of that edition of MA. I don't have the review and certainly wish I did.

DS.

Ok, I just wanted to make sure that the purchase of the Excelleron kit is well justified because I am very dissapointed from the quality of my Swallow. This is the reason that I substited the YS110 on that plane with an old OS60 Hanno and now my YS needs a home.

I think you will like the Excelleron 90. Even though I have had a lot of engine problems, I have flown it and love it. Most in this thread will say the same thing. Excellent choice. You will love it.

DS.

I hope I don't bore some of you with the following, however, I am so overjoyed I can hardly type. So, if you don't want to read it, just pass it by. I am a happy camper right now!!!

Here goes.

The OS 1.20 AX arrived today without fanfare. It was in an box at my doorstep. After the Evo issues I've put up with for the past four months, I sort of expected some kind of band playing somethiing, however, well, anyway... ha..

I removed the Evo yesterday evening in anticipation of the arrival of the new engine. So, when It showed up today, as expected, I was rather excited. I headed over to my LHS and picked up two props.. one 15-10 and one 16-8. I should be set for props.. at least for now.

I removed the engine from the box and took a good close look at it. I then grabbed my allen hex screw-drivers and checked all of the head bolts. All were very tight and seemed equal. However, one of the back plate bolts was just about finger tight. The other three were tight. So, I removed the back plate.. Bob, it's an O-Ring back there not a gasket. Anyway, I took a look around inside and saw nothing of consequence so I put it back together making sure that the flat part of the back plate was on top for piston clearance. After I put it together, I rotated the shaft to make sure I did it right. All was ok.

Next.. I took a look at the prop shaft. It is two sized.. 5/16 x 24 for the bolt and slightly larger for the unthreaded prop shaft. I have a reamer that takes that into consideration and so I test reamed an old broken prop (I knew I saved those old things for a reason) and mounted it on the engine. Nice and snug.

Next, I looked at the spinner backplate because I had it on the Evo 100. It has a spacer inside the prop shaft hole but the spacer was to small for the shaft and I don't know if I have one of the correct size or not. I must somewhere around here, however, I don't intend to use a True-Turn spinner so I really don't need that back plate. As a matter of fact, when I did slide the engine in place, there was good prop clearance and the large shaft spacer.. not sure of what the name of that is, has a groove in it that exactly matched the center line of th cowl.

Next, I said.. Ok.. let's see how it goes into the plane. I assembled the shock-mount parts from the ARF (used them with the Evo 100) and put them on the engine mount flats. It looked ok so I carefully lowered the engine into the engine compartment. I was absolutely shocked.. the bolt holes matched up perfectly!!! That engine and with that mount were the perfect match for the old installation. The throttle ball-socket matches right up with the throttle arm on the carb and the prop has good clearance from the cowl, and the engine looked square. What more can I ask for!!

Ok guys.. I'm anxious to test this engine and fly with it. Naturally, the weather forecast for this weekend sucks. Ok.. be patient, I know.. I know.

DS

I fly off a grass runway about 400x60 ft. Excelleron is a piece of cake to get in and out. The YS110 with 15x10 prop slows down nicely and is very predictable all the way to touchdown. I also have the longer ICEPOINT landing gear for a bit more ground clearance. So far, so good.
Gordie

CG, no boredem at all. I'm also anxious to see how the os AX performs. I've heard the engine is awesome. I have a YS 120 but it's pretty tired, so I may go with the OS also. Thanks for telling us all about it.

Also thanks for all the help/suggestions for my future Excelleron. My main purpose is to get better at presicion flight. Sure I can 3D several of my planes but from what I have noticed, all the top pilots were precision before 3D'ers. Perfecting point rolls, loops, etc may not look as cool as hovering but is more challenging to me. I have a heli when I want to hover. Is this a turning point in my piloting abilities?

Yup, its called progress

I ran the OS 1.20 AX yesterday for the first time.. ran three full tanks of fuel through it. Ran like a charm. Very nice engine.. plenty of power. I used the 15-10 I had for break in. I have a 16-8 that I may put on when I start to fly it, but only after I burn a few more tanks of fuel through it with the 15-10 (as suggested by just about everyone here). With that prop, I was turning about 9400 rpm at full throttle, but not leaned out for optimum performance.. running it very VERY rich, almost at the brink of switching over to "four stroke" from being so rich. But that's what everyone said to do.. how to run it in.

I am going to get several other props and keep them around and switch over until I find the one that the engine runs the best with and sitck with that one. Your suggestions are right on the money for what I intend to get, though, and expect that the plane will like them.

I didn't fly it yesterday. There was a nasty gusty cross wind and the engine was still not set right for idle. I will wait until I get everything ironed out and get a reliable run at idle before I get to serious with that kind of wind.

By the way, the engine has a needle valve adjust on the carb, however, it is angled rearward and the engine comes with a wire extenson that, once installed, puts the adjustment screw back a couple inches, definitely away from the prop. It was quite stiff originally, however, it had not had fuel through it to 'lube' the o'ring. Once I ran fuel into it, it became much easier to adjust but turns stiff (which is good.. it remains where it is set).

I started the engine with 2 1/2 turns out on the needle and it started right up. From there, I went to full throttle after a few moments of warm up and dialed in more fuel to richen it to operate a very wet 'four stroke' as I mentioned above which was about 5 turns. I alternated between very rich and slightly lean through the first tank. The second tank was set at just on the rich side of lean and ran the full tank through it at full throttle. The third tank was pretty much like the second except a tad leaner, but still wet. It ran just fine, transitions from idle to full were a bit hesitant at first, did about two 1/8 turns on the idle needle and that helped a lot... however, I am gonna wait for the pro's to work with me so I get the right combination of low end and high end for that reliable idle and good transition.

But.. all in all, I was VERY impressed with the engine, which is probably an understatement after all I went through with that Evo 100.

DS.

I am thinking about converting this plane to electric something like 8S. I've read all this thread but I haven't seen a photo that shows whether there would be room for the lipo pack. I'd be interested in any comments as to how easy this model would be to convert to electric.

Hi DS; Sounds like you had good luck with your break-in- I ran my new YS 110 in the Excelleron on Wednesday. Except for a little High needle adjustment It ran fine . I didn't have to touch the low end at all. The transition was great. Was running a 13.5X12.5 APC on 15% powermaster Very rich!!!. No signs of overheating at all. This 110 is a great engine. I'm running the stock muffler for now . I have several other props that I want to try ( 14-10 and 14-11) (15-10 and 15-11) I want to make sure that the plane slows up enough for final--We fly off a turf farm and the grass is a little high. Ground clearance becomes an issue at times.
Hope to maiden this weekend. Good luck with yours---Pete P.

Hi Pete.

Thanks for the update. I have been flying the Excelleron now for past several days with the new OS 1.20 AX and it has been a dream. The engine has all the power I need and then some.

One minor incident today, though. It was crazy. I was going through the Sportsman seqence, about half way though when all of a sudden the engine sound about doubled as though the muffler came off. Well, I immediately landed and saw that I had half of a muffler attached. It came apart at the center where the two halves join. The center bolt was missing. I thought it just came loose but I had checked all that stuff before flying so I was not sure what happened.

We said, "Well, lets go look for the other half, chances are about 1% of finding it in the area we fly in. Well,we walked over to the area over which I had been flying and sitting there, on the sand, was the other half of my muffler. The center bolt had broken. Not sure why. So, I had the two halves of my muffler but no bolt.

I will head over to the local hardware store and pick up a piece of either 8-32 or 10-32 all thread rod and replace it.

Other than that, this is a great combination..excelleron 90 and the OS 1.20 AZ.

DS.

DS- Is that the muffler with the long bolt through the center?? If so, the 8-32 rod sounds like a good idea with lock nuts on each end. Your lucky to have found it. What type of mount are you using?