Freya Evo notes ... U.S. version

This is not the instruction manual, just a collection of hints where they're needed.
Read your manual and this before you begin assembly.

Step 1  - Put the 2.6x8TS screws into the spacer/bearing assembly and press it in  until everything bottoms out before attempting to screw them in. If you don't, there  will be side play and binding in the assembly. The fit should be perfect and the arms should pivot freely.

Step 3  - Be sure to attach the body standoffs before putting the halves together.

Step 6  - Place the third bearing block in position (notch to the rear, bearing face up) in the upper frame assembly before joining the lower frame halves tightly. Once they're tight, it's much harder to get it in. I had 4 - M3 Lock nuts left over that would have gone had there not been a third bearing block.

Step 8  - Since the auto unit is assembled, I elected not to take it apart and check it. I wish I knew if it was properly lubricated at the factory. I'm assuming it was because Hirobo put it together and they do things right.
Once the main shaft is in place, about 1/2 inch should be sticking out below the 3rd bearing block. Or, if you don't have an eye for a half inch, 96.5 mm should be sticking out above the shaft collar.
Don't worry about the gear mesh on the second gear. Once you get all the bolts tight, it will be perfect.

Step 11 - Be sure to set the damper rubbers on both sides before installing any screws. Also, be sure to put the small bearing collars in before inserting the hub. It's best to put the red Loctite 262 in the threads of the hub instead of on the screw. I used a toothpick to do that.

Step 12  - It's a good idea to assemble the axle without grease or Loctite to see if you'll need any shims. I used all four and it ended up perfect. I screw a couple Q tips in the end of the blade axle to make sure no grease gets in the threads as I put the thrust bearings ( greased ) in. I used a toothpick to put some Loctite 243 inside the axle threads.

Step 15 - I decided to try some SAB 620 30 gram paddles. Not that there's anything wrong with the stock paddles. I just wanted to try them. They're very easy to adjust and to my surprise were threaded for the Hirobo flybar. They were suppose to be for 8-32 threads.

Step 16 - I discovered a little slop in the swashplate. Check your swashplate very carefully after you install the balls. If you have any slop, take a 19mm socket, put it over the center ring and give it a good rap with a hammer. You  might have to do this more than once, but when you're done, the swashplate will be slop free permanently. FYI, I used a dead blow hammer to do this, not a 16 pound sledge.

You will have two small bolts and a 4mm set screw left over. The radius block included in the kit doesn't match the plans. Nor is it mentioned in the addendum or parts list. It is a bonus. The part number is 404730. That's a little $30 gift from Jeff Green...thanks Jeff! Jeff says he's going to update the addendum sheet to include this.

Don't bother with adjusting the phasing at this point. Save it until after step 17 or later...but don't forget to do it! Now is a good time to go over all of your frame screws and make sure they're tight.

Step 17-19 - No comment other than "Why can't everyone make stuff that fits this well?"
Adjust the phasing now... See the note at the bottom.

Step 22 - The pitch slider comes assembled, but I found it had quite a bit of play. Adjust the nut on the end of the brass sleeve so there is no detectable end play, yet the control ring still turns freely.

Step 23 - The t/r pitch control didn't seem as free as it should, which is when I discovered the play mentioned above. After making the adjustment to the slider (almost a half turn) and applying a little oil to the t/r shaft, things were better, but still a little stiff. I pinched the links with some smooth jaw pliers and that took care of it. I would not use a link sizing tool on this link. The fit is very close to perfect as is, and if any material is removed, I think it would be bad for t/r performance.

Step 26 - Mix only enough 30 minute epoxy at one time to do one end of one boom support. If you're brave, mix enough for two, but do the same end on both rods. Trust me on this one. You probably won't be able to get everything lined up and screwed together if you try to do them all at once...then you have a real mess. Be sure to have some rubbing alcohol and paper towels handy You'll get a better bond if you sand the inserts and the end of the tubes with 80 grit sandpaper before gluing them.

Step 28 - Be sure to have a test indicator handy when mounting the clutch. Initially my fan hub had .005 run out, which way too much. It only took a couple minutes to get it to .0002 (yes, that's 2 ten thousandths), but without the indicator, I wouldn't have known. After you bolt the clutch to the hub, check the run out at the top of the shaft. Mine was .004, so I turned it 180 degrees and that made it .0015. Needless to say, this was worth the time it took to check it. A smooth engine/clutch will put out noticeably more power than one that is vibrating a lot.

This is the indicator I use. Not cheap and we don't sell them. A good place to get one is This one has been discontinued, but just search for test indicators. Good brands include Brown & Sharp, Fowler and Starrett.

I am going to the 404716 engine mount. The stock engine mounts weigh 66.5 grams. The optional mount weighs 35 grams. That's an over an ounce for $44. I'm doing this strictly for weight savings, and I have to's probably a big waste of money, but an ounce is an ounce. In addition to the mount, you also need some hard 4mm washers. I used 2506040 because they come 6 in a pack and fit the screw head perfectly.

The washers that come with the kit are still used, but now they go inside the frames as shown. I laid the model down on one side, slid the engine in, then installed the other washers by jamming them in. The frames are very strong, but they will go in if you start them at an angle. Once the bolts are in, these frames aren't going anywhere!

Step 30-37  The servo plates that are included in this bag are for the collective. I used Quick UK servo plates on all of the other servos.

Steps 30 - 37 - If you are using a tool like this, to get the center to center dimension, add 33.5 mm to the distance between the links.  Remember this is an approximate length and will probably have to be changed slightly. I use the Futaba Servo Jig to locate the holes in the proper place on the servo wheels. Then I tap them with a 2mm tap.

Collective Servo. If you use the inner holes, the rod going from the collective arm to the Tee lever has some interference . I used a 2525007 ball to move the rod out. Ryan Witchey, who brought this to my attention, simply put a nut under the ball. If you click on his name, it will open a link to his page. I used the inner holes and had +11 - 0 - -10, which is fine for the initial setup.


Set up - I get a little carried away with set up...sorry. Everything here is assuming your servos are centered with no subtrim, especially the collective.

Don't bother with adjusting the flybar paddles until you have your swashplate level...perfectly level. Read on...

The very first thing you want to do is make sure your swashplate is dead level. How can you tell if the swashplate is exactly level? Simple. If the pitch of the paddles doesn't change as you rotate the head, the swashplate is level. Take these readings with the flybar level and the pitch of the main blades at zero. You can do this with a pitch gauge and your eyeball. With a model like this one, I get a little fancier. I use an auto leveling laser level and a laser pointer in the blade grip. I'm taking readings that are up to 20 feet away. The further you are, the more accurate the reading. Adjust the aileron rod and the elevator subtrim if it's off. If it's  off too much, make a new servo wheel with the holes in the right spot. You want to keep the rods and arms as square as possible. A tiny bit of  subtrim won't hurt anything.

 I also adjust my pitch using the same tools. My pitch gauge is 8 feet long with a resolution of about 1/16th of a degree. Since this machine has practically no slop in the control system, I can depend on these readings to carry over to the actual flying. The only thing that would mess it up is a warped rotor blade and those are pretty rare nowdays. If you're interested in the details, drop me an email.

All that's left to do now is attach the landing gear, plumb the engine and go fly. I hope to have time this coming weekend. More to come...

Note about setting the phasing. If you want it perfect, stick a laser pointer in one of the blade grips and project it on a distant wall. Lock the flybar parallel with the boom and level. Turn on the radio. Move the aileron stick back and forth being very careful not to disturb the elevator. If the dot moves up and down, the phasing is off. If it doesn't move at all, you're phasing should be perfect.

The first flight was very nice. I decided a while back to go ahead and put a YS 91 in it.  It started up a lot easier than I thought it would, but it was way too rich at the startup needle settings. I had to turn the hover needle in about 1/4 turn just to get it to transition from idle to hover. In a hover it required one click of right aileron. I put it on the Futaba 14MZ so I have lots of tuning to do, but the initial flight was very impressive. For the first gallon or so, I'll be using 690 SAB blades and then I'll try some 710mm blades. I think it could use more blade than 690s,, even at these needle settings. It was overly responsive, but I think about 30% expo should fix that.  More to come...later. I'm packing for IRCHA.

I've been flying the Evo90 more lately. I put a JR receiver in it so I could use my 10X. The 14MZ is a fantastic radio, don't get me wrong, but carrying two different radio systems around just proved to be too much trouble. I think now that I've done that, I'll be flying it even more. The YS91 is running great, but it sure uses a lot of fuel. I'm thinking about putting a .70 in it...but not just yet. I don't have enough fuel through the YS to even consider it "broken in", so I'm going to leave it in there until at least then. It's starting to tell me that it wants a little leaner mixture and I'm going to give it what it wants.


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