Bob, I am running an APC 15x6, OS F plug, and PowerMaster YS 20/20 fuel. The engine has the stock muffler and I am leaving the cowl on (with appropriate cut-outs, of course!). I am using the stock tank, mounted at the CG.

I had a *slight* problem when breaking-in the engine (which I did on the plane-- 20 minutes of running no more than 4K RPM). It would run fine and then start to surge. Turned "out" (richened) the regulator 1/4 turn and that fixed it! Needles are set at about what it recommends in the manual.

I hope that you get yours working. It really is a nice engine!

Let me ask you a question about the midrange/lo end adjusting screw. Someone told us that it functions like an airbleed? What is your information and what exactly does that adjustment do?

bob_nj,
You're right. The low end on YS91AC/FZ is an air bleed. To adjust the YS91, first adjust the high end like any 4-stroke engine, then bring it to a 2,000 rpm idle and see what it does. If it goes to idle, then speeds up and possibly dies, it is lean, turn the low end in 1/2 turn. If it goes to idle, slows down further and dies, it is rich, turn the adjuststment out 1/4 turn. When you've got idle somewhat set, got from WOT to idle, let it idle for 20 seconds, then roll on the throttle (not bang it on, 3 sec. from idle to WOT) and see what it does. If it backfires, throws the prop, and/or dies, it is lean, in 1/8 turn. If it hesitates, gurgles and takes a while to come up to rpm, it is rich, out 1/8 turn.
DKjens

DKjens, it sounds like you've done this before once or twice Thanks for the information! I'm still a YS newbie myself, but I really like what I've seen so far...

One question, should I wait to do this adjustment after I have a gallon or so through the engine, or is it ok to do now (have maybe 4 or 6 tanks through)? I am running the high-end about 500 - 600 RPM less than peak right now.

Good Stuff_bob

I've been flying mine for about 6 months as well. No problems at all with the landing gear because as you say the thing lands so light there is not much loading at all. But it only takes one hard landing to screw things up sometimes and maybe yourself and I are both lucky so far. I do have to laugh about those people that are doing harrier landings that rip on great planes because of the landing gear.

Has anyone experimented with light weight aftermarket gear for the bigger ucd? I haven't weighed my gear yet, but was wondering what's out there?
Does anyone know if the DuBro will fit, or what it weighs...
DuBro

RobertC,
Yes, wait until you've has 1-2 gallons through the engine to really mess with the bottom end. I would often taxi out with the igniter attached, run it up to 1/2 throttle, remove igniter, run it up to WOT, sestt idle a little high with the trim and fly. When landing you can turn the idle down with the trim or kill the engine over the numbers. I've rarely been able to get a sustained 2,000 rpm idle until well broken in.
DKjens

I have one that i "tricked" out. I cut the wing tips off, changed the color scheme, and added a saito 150 golden knight. power issue...I think Not!!

Question, are the 2/56 rods adaquate for this airplane?

thank you

John

NO WAY ! I built mine simultaneously with a friend. One of the few differences of opinion we had during construction was the rods. He stuck with the kit hardware; I changed mine to 4-40 stuff.

Several of his rods were bent after the first day up. His performance and stick response improved dramatically when he switched over to the 4-40 stuff......Right, Alain?

mt

jrjohn, I changed all the stock pushrods to 4-40 except for throttle. Many have found that they buckle too easily at 3D throws

4-40 it is! thanks. How about the plastic horns and hardware, di did you replace that too?

I kept the horns. Haven't had any trouble with 'em yet. Had to change the clevises out for the 4-40 rods.

mt

I used dubro 4-40 fastlinks on dubro HD servo arms, dubro 4-40 HD clevis and HD horns on the control surfaces, dubro adjustable horn on rudder. Don't mean to advertise for dubro here but just to let you know what I used

I used Dubro 4-40 swivel ball links , Dubro Safety-lock quick clip 4-40 clevises , Dubro or Great planes 4-40 steel pushrods, and super heavy duty control arms from servo city

I haven't had any issues. This setup seems strong enough to me.

I'll ask again before starting a seperate thread. Has anyone found lighter landing gear for the ucando yet? If I'm not mistaken, my stock gear weighs around 3.5oz. Thanks_bob

Here you go Bob

http://www.graphtechrc.com/Secure/ma...ngear.asp#misc

Just ordered mine

I looked up the landing gear, it's 24 bucks Not bad.... but $10.00 for shipping!!!! come on, give me a break. I'll find somebody else

Try talking to Mike(Graphtec) about the shipping terms. He could make some adjustments. I'll let you know how mine turns out.........

What's the weight on the aftermarket stuff?

Howdy all,

What has been the most popular choice of engine for this plane. I sure that this question has been covered in about 500 of the 1500 posts in this thread . I realize everyone has thier favorite (I do) and wanted to get down to the nitty gritty and and find out what are the top 2 or 3 popular choices of engines for this plane.

Sorry for re-hasshing a question that I'm sure has been answered at least 1 out of 10 posts...hehe

later, Ken

You are right. This certainly is rehash, but humor you anyway

From my experience the most popular engines for the UCD 60 are
[list=1][*]Saito 100[*]YS 90[*]OS Surpass 90[*]OS FX 90[*]Saito 90[/list=1]

Those 5 in my opinion are probably the most common. With that being said I've also seen people using Saito 120-180, YS 120, 2 stroke 60's, OS 1.08, and even RCS engines.

Now that the YS 110 is out I'd suspect you'll see a ton of people going with that engine. Give it a little more time and it will pass the Saito 100 as the most popular engine for the UCD.

Ya see that's useful information . hehe,...Thanks It's good to see them all in one place.

I have the 46 size and love it. So I'm thinking I'll have to have the 60 size too! That's rational thinking isn't it?

Thanks for taking the time....

Later, Ken

Look at the weight of the YS, and you'll see why the Saito 100 is the best choice. I have my UCD flying with a Saito 100, it has ricketship unlimited verticle. I just got done installing a Iron Bay regulator, I'll fly it tonight and report back

John