Sd Models 35% Yak 54 (built)

[sandtrx]

Hi guys n girls, Here is my latest project winding down, an SD Models 35% Yak 54. I picked up the Airframe from Chief Aircraft (nice living close enough to pick it up and drool at the rest of the stuff they have) This one had minor wing damage (one broken rib in each wing). I picked it up for $450 instead of the usual $900, it took 2 pieces of balsa and about 5 minutes to fix it. I'm fairly impressed with SD's quality, I went over all of the joints and reglued them, 'glassed the motor box and went over the covering with an iron and a heat gun, reinforced the landing gear plate and epoxied it as well. The only trouble i had was with the wing tube not sliding in the wings very well. A couple of days of punishing my last few remaining brain cells and i came up with a solution. I picked up an engine cylinder hone and a 12 inch extension for a wood boring bit and honed out the fiberglass tubes in the wings and the fuse, it made really short work of a crappy sounding task. No bashing my pilot, I was informed that my pilot bust that i got for the plane looked like my boss, theres no way in hell my boss is flying in my bird, there would be thoughts of an intentional demise, so a little Snap On tools bear went in instead. I picked up a vinyl cutter last spring to complement my cnc plasma table, I cut all of the logo's for this plane myself, (had max's permission on the FG logos).

Heres a rundown of the installed equipment

DA-100 running on 112 race gas and Klotz benol at 50:1
Bolly and Mejzlik 27x10 props
Pete Model carbon spinner
Duralite 4800 Li-ions
Smart fly turbo-reg
Smart Fly Power expander eq-10
sullivan skywriter smoke pump
Futaba 9 channel PCM receiver
hitec digitals on choke and throttle (cant remember the number)
Jr 8611's on ailerons x4
SWB self adjusting 2 servo rudder tray
Jr 8611's on rudder
Hitec 5955tg on elevators

[yakattack]

youre gonna love it!

[sandtrx]

heres some pics

[sandtrx]

i'm sure i will, the only thing left is balancing

[bob_nj]

Does DA condone the 112?

Isn't benol castor based?
Have you run that in a gas motor before?
If so, how did you make out with it?

Thanks
Bob

[sandtrx]

I'm not sure about da condoning the 112, I have a Honda 250R with a 370 kit thats set up with very high compression so the 112 is mandatory to keep from detonating, yes the benol is castor based. I've been running that combination at 50:1 for several years now in the bike with zero problems. Every year i pull down the bottom end of the engine and replace crank seals and crank bearings, pretty much just for preventative maintanance though, i've never had a failure in this engine, but on a bike i had a few years ago i was having trouble with it leaning out and couldn't get it right until i figured out that a crank seal was bad and pulling air in through it. Every crank bearing i've ever pulled out of it didn't show any signs of galling and there has never been any signs of the castor oil gumming anything up, cylinder wear has always been negligible. anyways, i'm confident in this combination and i don't have any problem or concerns running it in any 2 stroke i own including my chain saws

[main_gears_bent]

Very nice looking Yak, I'm getting a 30% SD in the Orange and Checker scheme next week (if the shipping gods smile on me).
I ran Klotz at 50:1 in my DA50R for about 8 gallons, then it started giving me problems, taking 30 to 40 flips to start, idle was terrible. I had ran Klotz in several two stroke quads and never had a problem with it so I was very hesitant to think it was the oil. I sent the engine back to DA, they told me that I was running "cheap oil" that caused the engine to carbon up to such a point that it stuck a ring and lost compression, requiring a complete rebuild, and then they added "and your ignition module was so weak that it won't fire properly so we are sending you a new ignition" (paraphrased). In my opinion the ignition module was at fault, not the Klotz, never the less it cost $182 and some change to fix it. I went to Amsoil 100:1, not happy, going back to Klotz 50:1 and mid to high 90's octane.

Good luck with your Yak, you won't be let down. Keep us informed on the 112 fuel, and be sure to post video of the maiden!

[sandtrx]

	Quote: Originally Posted by main_gears_bent
	Very nice looking Yak, I'm getting a 30% SD in the Orange and Checker scheme next week (if the shipping gods smile on me). I ran Klotz at 50:1 in my DA50R for about 8 gallons, then it started giving me problems, taking 30 to 40 flips to start, idle was terrible. I had ran Klotz in several two stroke quads and never had a problem with it so I was very hesitant to think it was the oil. I sent the engine back to DA, they told me that I was running "cheap oil" that caused the engine to carbon up to such a point that it stuck a ring and lost compression, requiring a complete rebuild, and then they added "and your ignition module was so weak that it won't fire properly so we are sending you a new ignition" (paraphrased). In my opinion the ignition module was at fault, not the Klotz, never the less it cost $182 and some change to fix it. I went to Amsoil 100:1, not happy, going back to Klotz 50:1 and mid to high 90's octane. Good luck with your Yak, you won't be let down. Keep us informed on the 112 fuel, and be sure to post video of the maiden!

thats odd, if you stuck a ring, and caused it to lose enough compression to fire, you would be able to tell when you flipped it, imo as well it was the ignition, another thing that i've found in my experience with all out race engines were reed petal problems, i had several different types of reed valves on these engines and periodically i'd have to flip the petals because they would not seal tight againt the reed block, i would imagine that the da's have the same condition, the reeds flex so many times (once per intake) that they inherantly weaken, but all i ever did was take them off of the block and reverse them, then i bought a couple of the v-force delta valves with carbon fiber petals, they didn't weaken, but i did break a couple of petals and i can't imagine that broken carbon fiber going through crank bearings, rod bearings, wrist pin bearings and scuffing the cylinder walls could be any good for anything.

hopefully i can get all of the honey do's done shortly (taking apart my front deck and planing every board and restaining, if it wasn't redwood i'd replace it!) and get the yak balanced and in the air, i'll definately at least get pictures.

[main_gears_bent]

I have actually flipped my reeds twice since i have had the DA, the first time was before I ever started it, I pulled the reed block and one was about 8 to 10 thousandths from sealing. Good luck with the Yak (and the honey do list), and thanks for your input. Happy flying.

[cropduster48]

I am running a Da 50 on a 28% Edge 540. I have run lawnboy oil at 32 to 1 sense day one. Best running engin I have ever owened, and easeast to start. Never have had problem one.

[bgold]

I've been flying the same plane and similar set up since Dec and you'll love it. Bel-ray H1R @ 50-1 no carbon build up no problems. I did send the DA to Sala for mods before I ever flipped it over. Runs strong, smooth transition and gobs of power. It will pull the Yak straight up out of sight. Swinging a 28 X 10 Mejzlik and running regular gas from what ever station is near. Don't over think the engine.
Bill

PS I used lawnboy ashless @ 32-1 for the first 4 gallons.

[EDGE-540]

Do any One hav a set up Of 35% yak + smoke system ??