diamondave

My Feedback: (29)

yeh that ef yak is huge no doubt, flies great too, i thought all the cf props were the same as far as construction, i may break down and get one, i think my super80 will be fine with it, i can try the one ihave but wont fit with backplate, holes are a tad off, so either run without spinner or backplate, or just go ahead an order and hope i turn it good enough, last check iwas getting 63-6400 with the mej 26-10, on my 100 i droped 2-300 i think from mej to biela, so that was my concern, mike with rcs(tbm) said to try and stay above 6k rpm on the ground, im thinking it should, plus being a different motor, longer stroke and all that jaz from the 100, it may not drop as much, tough to say...

diamondave

My Feedback: (29)

well i tried my black/yellow biela 26-10 from my other plane today, i liked it, it did drop some rpms from the mej, but flew just as good if not better, had more low end grunt like you said, pulled out quicker with the lower rpms, the mej was a tad faster in a straight line horizontally i think, but i usually dont fly fast anyway, so i will order the white/red now given how cool it looks....if anyone is interested i will list my mej on the marketplace soon, i have a 26-10 regular and a 26-10N, which they say is good if you want a tad less load and a tad more rpm, it performed very similar on this plane anyway, they are close in size until the last 3-4 inches from the tip, the narrow tapers off quicker at that point, anyway i will list both and keep which ever doenst sell as a spair i guess....

diamondave

My Feedback: (29)

bterry here is a short clip of the ef yak from yesterday, i know its not the thread but thought youd like to see it again, maybe it will swade you to get one...i have another vid on there of it as well, getting down and dirty in the other one...litterally, haha


http://www.youtube.com/watch?v=dsHauR64fmk

BTerry

My Feedback: (8)

Looks great Dave, thanks for posting!

That thing seems to fly great with the ZDZ-100. Maybe I will get one in a couple of years, it would be just about perfect on my BME 110.

For now I am content with my AM 33% Yak. Still working out a few bugs before I can fly it (need a rebuild kit for the carb and am fighting gremlins in the power connectors on my Smart-Fly EQ-10... I need to replace my power connectors and ~3' long power cords to see if that will fix it).

I can't wait to fly it. Judging by the way your ZDZ makes your big Yak climb as evident in that vid, my little 33% Yak will be downright scary on my BME!

MIXMASTER

My Feedback: (15)

Have 30 flights on my 33% TTOC Yak now, very nice plane, I like the difference with extra weight & size(have been flying 30%), although mine is 24lbs, pretty far off from the 19.5 in the ad. The 3W80 is about 1lb more than DA85(incl. mounts) but still more weight than expected. With 24X12 Xoar I get 6400R's and fair pullout, plenty of control in hovers & harriers, I needed this prop for more prop clearance, the 26" was in the grass. The plane came out slightly nose heavy but I like it this way, still floats on landings, inverted harriers are better. It flys much better than my 30% SD Yak, far less aileron needed to correct harriers and I have plenty of rudder for inverted harriers. It also does pretty fast TR's too, very easy to keep it straight up. The 3W throttle response lags my DA's, its nice to have instant power when needed, but I could keep on turning in the low needle & see how far it will go, it's already been turned in a bit. Over all, top notch plane-build & flying, it matches E.F. IMO.

diamondave

My Feedback: (29)

your 110 would fly the big ef yak well, in this 33% that would be nuts, mine is in the 23lb range with dual batts and stuff, i have a zdz super80, 26-10 prop, its a rocket pulling out imo, i just ordered a biela white/red, seems to work better for me than the mej for this plane, will try and get some pics and/or vid this coming weekend, i dont have any vids of this one yet, a few pics of me hovering a while back, but need some real life action looking stuff, haha.....

diamondave

My Feedback: (29)

ive had good luck with zdz's, i have had the original 80cc(discontinued), a 60cc, my 100cc, and now a super80, some of the guys around here give me hazing cause im in da country, they are right across town, but i like to be different, and ever since my 1st zdz i was hooked, service was great, pricing on new engines was discounted for being a repeat customer, the only time ive ever had to send one in was after a crash to be looked at, thats the only downside to not having a da, i have to ship mine out, but its acutally quicker for me to make it to the ups store than to get all the way down to da...and i get alot of compliments from spectators, even people that come out sometimes not in the hobby, they say my motors sound the "cleanest" , no spuddering and missing that we here from some of the da guys, i know tuning can help it, but there is many da's here and i hear mid-range gurgling on more than one, i know its no big deal really, but to untrained ears mine gets the compliments....

Patto

I've found that to be really common with the DA's. My 3W85xi weighs considerably more than the DA85, but it does not have that mid-range gurgle and the low-end torque is a lot better. It's all a trade off, and there are strengths and weaknesses in both designs. I would not hesitate to buy a DA if I had the money, but for now I'm all about the 3W's.

ZDZ's are nice too, but I'm not a fan of their rotary valve design. Again, it's all about personal preference.

diamondave

My Feedback: (29)

yeh some say thats a good thing some say not, ive been happy with all mine i got to say, im not saying i wouldnt be happy with a da either, my buddy just fired up his 85 in a new h9sukoi, motor is strong, too loud with his pitts muffler imo, but its a powerhouse for sure, so far my motor/airframe selection has worked out well, havent been totally unhappy with a zdz cause of lack of power in any of the planes, just had to try some different props to get it exactly where i wanted it, which is true for any motor i suppose, its all good

MIXMASTER

My Feedback: (15)

Its strange to me, after reading up on the tilotson carb, I thought maybe 3W engines would be better than DA w/ Walbro as far as transition anyway, but I like my DA's super clean and immediate response over the 3W, no problems with gurgling, running rich here. You do have to tune after break in and change from breakin prop to the best one for transition. I found out you do have to try several props before you get throttle response and high end peak. The Vess props are so different than most, you cant go by the standard pitch numbers and 8=A, B=10, C=12 doesnt really work either. Props can vary a lot in airfoil thickness, cord, and taper at the tips, huge differences.

Ih82crash

You could get kicked off some of the threads talking like that! I found the same thing to be true, but nobody cares to believe it. They all say the needles aren't adjusted or the prop is not balanced. I just bought a 3w85cs and am going to compare it with the da 85 and the 3w 85xi.

I ended up crashing my 33% yak. It was a dumb thumb unannounced landing. the good news is all I needed was some glue, covering, a new canopoy, a new prop and a new stab tube. She is ready to fly again this weekend.

diamondave

My Feedback: (29)

least you got her back together quick, thats always nice


vess props are interesting, for some reason ive had good luck with them on both my ef planes, the 88" yak loved a 23B, and my 110 loves a 27A, tried a 26b on this plane with my 80cc and didnt like it, spooled up nice but seemed to peak out and the motor wanted more, its hard to describe, but i like a regular 26-10 on this one, and i dont by that A=8, B=10, C=12 either, my 23B seemed to be very close to a 23-8, but the 26B was closer to a 26-10, and the 27A suprised me, seems to be just as fast as my 26B and gives me better pull out, i was concerned to buy it thinking it may be too flat for forward speed, worked out just perfect though, even though it tachs less on the ground, throttle responce is excellent, when you get the right combo with a vess they are hard to beat, reminds me of a torque converter, knows when to lock up and when to freewheel, i dont know, something like that

Patto

On the contrary, the 3W's are known for a slightly better transition than the DA's, possibly because of the Tillotson carb; whereas the DA's usually have a slightly better top-end. If your 3W is not transitioning correctly, and no amount of tuning is fixing the problem, you need to send it in to Aircraft International, (I never recommend Cactus Aviation, as a general rule). Chances are you have a cracked diaphragm, warped reed, carbon build-up, or one of a few other issues that are beyond simple tuning.

3W's are well-known as having excellent low-end torque compared to the DA's. DA's are known for being substantially lighter and developing more RPM's at the top-end. Like I said before, they are both great, and I would not hesitate to buy either, it just depends on what you are looking for. Then we can throw the ZDZ's into the mix, with the great consistency of the rotary valve, etc.

Regardless, your 3W has an issue and needs to be serviced.

diamondave

My Feedback: (29)

got my white and red biela prop today....i repainted the tips orange, i found some that matches the plane pretty good, the red looked good, but i wanted to waste time and frustrate myself by sanding the tips and trying to get a nice finish[:@]....it turned out okay eventually, should give it a whirl this weekend, not sure sat or sun, but one of them, i will bring the camera, get some pics and maybe a vid

BTerry

My Feedback: (8)

Meh, just balance it. It will look fine when it is running. Of course that means you will need to keep it running all the time

I am a bit late to the conversation, but I LOVE my ZDZ's. I love all of my engines, but the ZDZ's (40's and 80's) just work great for me. I have several different types and for me, nothing matches the precise transition and smooth power of the ZDZ's. My dad and brother have several DA's and they are fabulous, smooth, easy to use, powerful, etc., but the low midrange burble/popping makes me nervous sometimes.

FYI do NOT NOT NOT!!! run less than 40:1 oil ratio in a ZDZ.

diamondave

My Feedback: (29)

me too, yamalube R at 40-1, im amazed at the da's and 3w's even running at 100-1, i know its synthetic and all that, but that seems like not enough lube, anyway, got the prop balanced, needed a touch up on one side, looks good though, my orange is close to the red, its suttle, which is good the red was a nice primer...will take pics soon, maybe once its on before i get it to the field, i just figured with the wings on and being out in the sunlight will be the best pics

diamondave

My Feedback: (29)

well its thursday monring, getting ready for work, looking at the prop now im glad i painted it, looks freakin sweet i think....i will try and get it mounted later today if all goes well, now i have something to daydream about at work today

Richard D Bahmann aka/Wrongway

My Feedback: (42)

A CDL driver day dreaming.....scary thought.[:-]

BTerry

My Feedback: (8)

The reason for this is simply because the rotary drum requires this much oil to maintain its seal. Running even at 50:1 I have found I start chasing needle settings all over the place and running becomes inconsistent. I can't even imagine how it would run on an 80:1 ratio, and I have seen numerous pictures of destroyed engines running at low ratios (referring to oil content, not numerically) like that. My friend Dick Hanson runs them all (40cc to 200cc) at 32:1 on Honda or Redline (can't remember which) and they always run like a top and are as clean as brand new engines. Yamalube at 40:1 is great too.

DA's and my BME twin are reed valved engines. That fact combined with the metallurgy allows them to be run at the leaner ratios than ZDZ's like but it is easier to just run the same mix in everything.

Now that I think about it, my Dad runs his DA twins on the same ~40:1 Redline mix as the ZDZ's and they run great too. He gets a bit of black on the stabs and underside of the fuse, but a quick wipe with Simple Green degreaser cleans it right up.

Dave, can't wait to see your plane with the Biela. I think you will like the way it flies!

diamondave

My Feedback: (29)

got the prop on, looks great, had to cut the spinner some more cause its wider, i will wait until the weekend for pics, i think with the wings on out in the sun pics will do it more justice than in here with the lights on.....

diamondave

My Feedback: (29)

in my mind im flying all the time.....when i get off the highway down a ramp i pretend like im coming in for a landing, haha

diamondave

My Feedback: (29)

i was wondering if i could use the same fuel if i ever got a da, i know if i had 2 cans i bring the wrong one sometime[:@] , i think my buddies with da's are running regular grade too, im running 92-93 whatever the super is at the stations per mike, i think someone with a da told me its cause zdz has higher compression? not sure

BTerry

My Feedback: (8)

No problems at all, the DA's love it. They typically only need 87 octane, but 92-93 won't hurt a bit.

Steve

My Feedback: (54)

I've found that I actually get better power running 87 fuel over 93. Don't know why, but I do get better power in my BME's and DA's. I run 50 to 1 mix. I used Amsoil all last year and switched back to petrolium based oil this year. I have not noticed any differance in performance yet. I'm waiting to see if my DA 50 starts to get a little better compresion over time. Its always been the easiest to turn over on startup.

I think the BME 110 is tooooo much power for the TOC Yak. I have to adjust for thrust too often. I'm going to try and find a BME 102 to put in it next year, when I use the 110 for another project. It is a fun plane to fly though. Just not good for presision with that engine.

BTerry

My Feedback: (8)

The lower compression engines are capable of using the faster burn rate and explosion rate of the lower octane fuels. You are absolutely right, you will get more power out of a lower octane fuel (up to a point). Typically racers will use a HIGHER octane fuel specifically to decrease the tendency to preignite when they increase compression in the engine, run an intake boost (turbo or supercharging), etc. The Reno Racers run 130 octane gas, a couple of oxygenating liquids, and then fog water spray into the intake manifold to make the air more dense, then run extremely high manifold pressures and hope the 65 year old, half million-dollar engine holds together.

However if the octane rating is too low for the engine as a system it will cause preignition problems and could destroy the engine. The ZDZ will certainly blow up running gas with too low of and octane rating or too little oil, the forums are full of threads blaming the engine itself when one of those two problems are almost always the culprit.

Now that my ZDZ 80 is on a shelf and the BME 110 is in my Yak I will probably run 87 octane for my BME and Taurus 52. They run great on it. In the future when I put my BME in a larger plane and swap my ZDZ back into my Yak I will go back to the 92 octane. For oil, my non-ZDZ engines love Stihl Ultra @ 50:1, as long as I wipe off the carbon in the exhaust port every 100 hours or so. Redline at 40:1 works great for me too.

Steve,
I only put the BME in my engine because I saw it for a good price, noticed that you had installed one in your plane, and I was far too lazy to modify the fuse in my Yak to hold the canister for my ZDZ (it was 3 inches too long for the tunnel). Using my wife's logic, I bought the new engine because I didn't want to buy a Pitts muffler for my ZDZ. That's my story and I am sticking to it! It sounds from your experience that the 80cc single would be about perfect for the plane, so I guess I need to work hard to get a smooth throttle curve on my BME monster.