DA85 on pipe! Results please.

[Henna_Ojisan]

Shaun,
Congrats!! I flew again today and without touching the needles was getting 6480 on the Mej 28x10. I'm at about sea-level here and the temps were in the low 80's F. It's running great and the power is awesome compared to the weight. Interested in your install pics as well.

I have a 32oz. tank as well and the motor isn't as thirsty as I anticipated. I'll probably change to a 24oz. tank at some point here.

Glad to hear all went well!

[krayzc]

good deal Hana,

I also swapped out my tank while I had my motor in for the bearing replacement on the front hub and i still am coming in with 1/3 tank yeah baby power and not thirsty......

[sprice50]

I think I'll just leave my 32oz in. Plane flies great just the way it is

[Flatlandman]

Sprice50, forgive me if this has already been covered but how much work did you do to get the da85 with the pipe to balance?

[sprice50]

	Quote: Originally Posted by Flatlandman
	Spice50, forgive me if this has already been covered but how much work did you do to get the da85 with the pipe to balance?

Good point. No work at all - keft it the same as when the BME 110 on stock muffs was there. With the 2x5cell GP 2000 NiMH batteries in their stock location and one 4 cell pack in the motor box it balances perfectly.

Why did it work out so perfectly, well, I checked the pipe location and then holding the pipe with my thumb and middle finger I let the pipe pivot from that same point and placed a scale under the rear of the pipe to check the force at the rear of the pipe - it measured 100g on the scale. I then noted that the moment arm from the wing tube to the rear of the pipe was approximately equal to the moment arm from the wing tube to the prop. I weighed the Mej 28x10 and it was 100g heavier than the Vess 27B I had installed before... Perfect there should be no effect. I assembled it all and checked the CG. No problems there.

I'll post install pics and a write-up tomorrow.

[krayzc]

how did u like that 27B prop?

[Flatlandman]

So the sum of all torques equal zero hehe. Nice use of mech physics volume one in the explanation.

I didnt realize that the 110 would balance the AW E260 with the batts in the stock positions.

[sprice50]

	Quote: Originally Posted by krayzc
	how did u like that 27B prop?

"Also tried a Vess 27B and got 6350 which surprised me. Another surprise is that it was WAY nosier even though it was spinning 100rpm less."

Prop was good, but nosier and pullout was better on the 28x10. The Vess was easier for hovering and I attribute this mainly to reduced gyroscopic effect (less mass).

[sprice50]

	Quote: Originally Posted by Flatlandman
	I didnt realize that the 110 would balance the AW 260 with the batts in the stock positions.

when I spoke to Rocco at aeroworks he said they designed the motor around a 5lb engine to allow a range of 4-6lb setups with use of various spinners etc i.e. you could run a DA100 on stock muffs with CF spinner and wood prop and place the battery on a rear tray or run a lighter engine with Aluminum spinner, CF Prop. I also have a ply mount for my DA85 which adds about 1/2lb to the front (this was on the BME also). I use the stock tailwheel assembly.

[tbrum]

	Quote: Originally Posted by sprice50
	DA85 / KS1090 pipe / 25mm drop flex header Henna - my results were pretty much identical ! First run of the DA85. Engine not drawing fuel so removed the plug and blew through the vent line while spinnging the prop. Choke on. Popped on first flip, flipped once more per instructions. Choke off, flipped three times and she ran. Throttled up and it sounded rich, so reduced the low 1/4 turn. Started it up again and after 30 secs went full throttle. 6450rpm on a Mej 28x10 on first run on Castrol Super 2 non-synthetic 32:1. No midrange issues and smooth transition throughtout the throttle range. Field temp around 18C, altitude about 500ft. Flew 5 tanks through her - AW 35% 260 AUW approx 26lbs.. Consistently, 6400-6450 on the setup. I couldn't believe that a 32oz tank lasted over 17 mins at half throttle or higher. Climbout from hover is great and it is whisper quiet at 1/3 throttle or lower. Temped the engine imediately after landing: head 165F, 3 fins down head 185, header at engine 230F, rear pipe 120-130F. Ran clean and so I had no cleaning to do which was great. So that is now 3 confirmed 6450-6500 results on a 28x10 Mej with a DA85 on KS1090 pipe. (tbrum, sprice, henna_ojisan). All engines are still in break in! All of us used stock DA headers; mine was a 25mm drop flex header. Also tried a Vess 27B and got 6350 which surprised me. Another surprise is that it was WAY nosier even though it was spinning 100rpm less. So I'll be sticking to the Mej 28x10 on this one. Will post detailed pics of the install in the Aeroworks 260 later this week. Took about 12 hrs but I have very limited space in my house to build which slows things down! Was well worth the effort.

Hey Shaun... congrats on the maiden... I'm really happy you and Henna got the same performance numbers as I have.

I hope to maiden mine this coming weekend, provided the feild dries up enough!

I got 2 more tanks throught my engine again in the airframe (anchored to a post - therefore static run-in)... after about 10 - 24oz tanks of 32:1 Pennzoil Air Cooled mixture and playing with the needles, I'm now logging consistently 6680 rpm on a Mejzlik 28x10

To Henna's point.... it just keeps getting stronger!!

Cheers

Trev

[knifelander]

you guys have about sold me on trying the 85 on my carden 330, i guess you like the mej 28 10 the best . also i guess the ks 1090 is the way to go, i talked to da and they said they had a greaves pipe for but do you think it is to small . thanks leonard

[Henna_Ojisan]

Shaun-
How long do you think it is from the exhaust port on the head to the leading edge on the pipe? I have the 50mm drop header so I'm guessing my header is a tad bit longer. What is your spacing from the header to the pipe inside the coupler? I think I'm around 3/8" betweeen the two...

The other question I have for the pipe gurus - I envision that we need to avoid leaning the top end all the way because as the motor comes on the pipe, the ratio of air to fuel will change and the motor will lean out a little bit. Does this sound right? This is my first tuned pipe and I'm keeping an eye on temps just for that reason...