The 'What did you do in your workshop tonight?' thread

[Rusty 73]

Xpress

So have you flown a DA100 ?
Okay then I know your into the 3D stuff and hanging off the prop and over heating your engine, that's cool if that's what you like .
But just saying the 120 is as smooth as the 100 is like comparing the DA170 to be as smooth as the DA150 and is not .

You can say it's airframe and what ever other thing you think would be a good or valid excess but it's not .

Do you balance your props before running them , even thought the factory says its balanced . This makes a huge difference , I just balance a new Mezjlik 28x10 and 28x12 , they required a couple of grams to proper balancing to eliminate and vibration from the prop .

Yes the DA120 isn't as smooth as the DA100 , just phone DA Dave or ask anyone of the techs them yourself ,they will set you straight .

 

[dhal22]

I don't know about DA 100's but my 120 is a rocket launcher. With no 100 experience I haven't noticed excessive vibration on the 120. I would say my 3W-106 is smoother though.

 

[Rusty 73]

My 120 is very much a rocket performs even stronger when i fly near to sea level .
I'm just getting a smoother idle now after sixty ten minute flights.
Yes the 3W and ZdZ are smoother running and the ZdZ is still more powerful than either .

 

[Snoopy1]

Don't know what DA120's you've ran, but the 2 I've owned, and all the ones on my buddies airplanes, are just as sooth as any other 120cc class engine.

Airframe has a LOT to do with how smoothly the engine 'feels'. Even things like exhaust setup, or how the engine is mounted, or even the propeller can affect it. It's not as cut and dry as, 'Oh the DA120 is a rough engine'.

Welll my two cents on this let first state that I own a 100 and not 120. But when I was building my ViperST from Terry he made it very cleat not to put a 120 into it as the plan was not designed for it was to rough and if I would like to put a 120 into it I should buy a DLE. Therefore me being a DA fan I bought a DA100 for the plane. What I do agree is that a DA 170 and DA 150 is no comparison had both still have the 150 but sold the 170. The 150 is a much better engine runs smooth and I mean smooth just a great engine to live with starts easy and never needs to be retuned or fiddled with.

 

[WMcNabb]

Welll my two cents on this let first state that I own a 100 and not 120. But when I was building my ViperST from Terry he made it very cleat not to put a 120 into it as the plan was not designed for it was to rough and if I would like to put a 120 into it I should buy a DLE. Therefore me being a DA fan I bought a DA100 for the plane. What I do agree is that a DA 170 and DA 150 is no comparison had both still have the 150 but sold the 170. The 150 is a much better engine runs smooth and I mean smooth just a great engine to live with starts easy and never needs to be retuned or fiddled with.

Ok, now I’m officially jealous. Didn’t know you had a ViperST. Cool!!

 

[Xpress]

Xpress

So have you flown a DA100 ?
Okay then I know your into the 3D stuff and hanging off the prop and over heating your engine, that's cool if that's what you like .
But just saying the 120 is as smooth as the 100 is like comparing the DA170 to be as smooth as the DA150 and is not .

You can say it's airframe and what ever other thing you think would be a good or valid excess but it's not .

Do you balance your props before running them , even thought the factory says its balanced . This makes a huge difference , I just balance a new Mezjlik 28x10 and 28x12 , they required a couple of grams to proper balancing to eliminate and vibration from the prop .

Yes the DA120 isn't as smooth as the DA100 , just phone DA Dave or ask anyone of the techs them yourself ,they will set you straight .

Yes, I have flown a few DA100's actually, and there is no discernible difference between them and the DA120 as far as'roughness' goes, not to me.

My engines do not overheat, even in a full 8 minute hover- if that's the way you would like to have a conversation then we're done here.

By the way, Dave Johnson and Casey Johnson are personal friends, (Colton Clark as well for that matter, though he doesn't work at DA anymore). They haven't agreed with your assessment.

 

[Xpress]

Welll my two cents on this let first state that I own a 100 and not 120. But when I was building my ViperST from Terry he made it very cleat not to put a 120 into it as the plan was not designed for it was to rough and if I would like to put a 120 into it I should buy a DLE. Therefore me being a DA fan I bought a DA100 for the plane. What I do agree is that a DA 170 and DA 150 is no comparison had both still have the 150 but sold the 170. The 150 is a much better engine runs smooth and I mean smooth just a great engine to live with starts easy and never needs to be retuned or fiddled with.

He specifically designed the kit for the DA100, the DA120 won't fit without some heavy mods. If you're willing to change a lot of things to get the DA120 to fit, then there wouldn't be an issue with it.

 

[Terryscustom]

The Viper ST "KIT" version was designed for the DA100 and DLE100 / 120. The DA will not fit the cowl and the smaller wing span and lightness of the air frame make it very torquey when you start running DA120 props like the 28x10 and 29x9W It causes ill effects on flight performance. A DA120 does not vibrate any more or less than anything else. The very first batch that they made did but those are long gone unless you find a 6+ year old 120 that has never been updated which is not likely. Engines like the DA120, GP123, ZDZ112 and anything larger also run way more smoothly on canister exhaust.

 

[Luchnia]

The Viper ST "KIT" version was designed for the DA100 and DLE100 / 120. The DA will not fit the cowl and the smaller wing span and lightness of the air frame make it very torquey when you start running DA120 props like the 28x10 and 29x9W It causes ill effects on flight performance. A DA120 does not vibrate any more or less than anything else. The very first batch that they made did but those are long gone unless you find a 6+ year old 120 that has never been updated which is not likely. Engines like the DA120, GP123, ZDZ112 and anything larger also run way more smoothly on canister exhaust.

I think the perceived "roughness" is because the transition between the DA100 and the DA120 are different and of course the extra power comes into play as well as prop setups. If you take the extra power alone, that would do it.

My DA100 (not L) seems to be always silky sewing machine smooth, whereas my two DA120s have a roughness about them in comparison. I switched the DA100 out of a plane and put the DA120 in it and I could tell a slight difference in what one would call smoothness. Again, though this may be perceived because of the difference in power and transition. I recently took one of my DA 120s off of canisters and I can really tell a difference in the way the engine performs. There are quite a number of variables that come into play between engines that are 20cc different.

 

[Luchnia]

The Viper ST "KIT" version was designed for the DA100 and DLE100 / 120. The DA will not fit the cowl and the smaller wing span and lightness of the air frame make it very torquey when you start running DA120 props like the 28x10 and 29x9W It causes ill effects on flight performance. A DA120 does not vibrate any more or less than anything else. The very first batch that they made did but those are long gone unless you find a 6+ year old 120 that has never been updated which is not likely. Engines like the DA120, GP123, ZDZ112 and anything larger also run way more smoothly on canister exhaust.

I re-read your post and I think both of my DA 120s are well over 6 years old. I have not sent either one of mine back to DA, but was thinking maybe next winter I will do that.