H9 35% Extra 260 w/DA 85

[walkerk122]

I was flip-floping back and forth DA 100 vs DA 85 until I saw QQ's Python with the 85/Greeves this past week at the Nall...no shortage of power (understatement!!)and it spooled up so stink'n fast! To avoid flip-flopping any longer I marched over to the DA booth and bought an 85!!

Anyway, does anyone have any experience with the 85 on the H9 260's? I'm either going to go with a KS 95 (sitting in the shop) or a Greeves (backordered from DA until the end of the month). My only major concern is balance!

[Extra nuts]

WOW, your going for it. Cool. I cant wait to see reuslts from your first few flights. Will you post em here? I am curious to see if it will have the same performance as a DA-100 in the same plane. I run the DA-100 in my 35% H9 extra 260 and its so sweet. Now i hear there is a new and improved version of the da-100. Seen one in leseburgs 260. It seems to have much more power than the originals. But, i also have heard reports that the new 85 has the same power or can spin the same size prop as the 100. Wish you the best of luck. You will love that plane. It flys ultramega OK.

[walkerk122]

We have another H9 260 with DA 100 (Dizane) at our field for side by side comparison. Should be interesting!

[Extra nuts]

Oh man that should be good. It would be cool if you could get video of them both hovering side by side than going vertical like a drag race.

[bodywerks]

	Quote: Originally Posted by walkerk122
	I was flip-floping back and forth DA 100 vs DA 85 until I saw QQ's Python with the 85/Greeves this past week at the Nall...no shortage of power (understatement!!)and it spooled up so stink'n fast! To avoid flip-flopping any longer I marched over to the DA booth and bought an 85!! Anyway, does anyone have any experience with the 85 on the H9 260's? I'm either going to go with a KS 95 (sitting in the shop) or a Greeves (backordered from DA until the end of the month). My only major concern is balance!

your only major concern is properly mounting it! You cannot use standoffs on the DA-85 - it will void the warranty. With the H9 260, the engine is spaced out so dang far, too, so making a mounting block out of solid ply would add a lot of weight. I have had good luck with end-grain balsa blocks, capped with two sheets of 1/32" ply(compression-glued), on engines up to 150cc - it may be an option.
Given how far out this setup is, though, I would consider making a sort of pyramid with the top chopped off out of the end-grain balsa, cap the front as mentioned before, then glass the whole thing with 3/4oz glass (except the back part - you'll need to glue the assembly to the existing firewall). Weight gain would be minimal, strength would be phenominal.

[Mark Davis]

I had this combination and it flew very well... No need for a tuned pipe or can... Plenty of power with an in-cowl pitts-style muffler...
Balance was not an issue...

[Extra nuts]

How bout some pics or video. Do you have any of your plane. Also i got to say that this is one of if not possibly the best ARF ever made. It flys go perfect, its mezzmorizing.

[walkerk122]

[quote=bodywerks;458832] You cannot use standoffs on the DA-85


Missed that one in the instructions, thanks for pointing that out.


Bodywerks, what did you run for exhaust? All I could see was the header. Did you run the rudder servo push-pull in the tail?

[bodywerks]

Those pics are of my 85 in a 75cc Extra, and of my 150 in my 42% Extra. I have a 100 in my H9 260 on tuned pipes.
On the 85, I went with the KS95, which worked very well. I would suggest the same for your plane. The pitts mufflers are WAY, WAY too loud!
You should still be able to mount your single rudder servo in the tail and be able to achieve a good, if not at least flyable CG without adding dead weight. If you are not going to IMAC it, don't add the pilot. My batteries (3-2S A123's) are all located just behind the first fuse former to achieve a forward CG for IMAC.

[mflander]

Body: Did you notice that the ks95 made it real peaky around the midrange? I switched to a MTW110 and it was like a whole different motor, midrange was very smooth.

[Vic3D]

Go for the KS-1090 pipe. Plenty of videos around here of this set-up and it is insane.

[harv]

thats a good combo. but some people ahve been saying on a plane of that size, the 85 can out put the RPM of a DA 100 with the same prop, but not the same torque. EG. in a hover it doesnt punch out like a 100. Ive only seen this on one plane so i cant tell you not to. would be a really light combo though.

harv