Help With Motor Timing and Poor Throttle Response (Gecko 120HV)

[gyro]

I will end up trying to fly it as soon as I get back from vaca. I really don't need to fly it to see that it just doesn't have the burst power as my mxs. Its just so obvious. Like I said, if I was to firewall the mxs and try to pull it back, it would take off like a rocket. The extra will move a few feet. I don't know of its the prop, I have a 16x8e falcon on the mxs, and the extra has the 20x8 XOAR

Are you on 12s with the 4330-215?

(Going off what you posted in first post)

What are your watts/amps? Should be going for about 2700-3000w on 12s. If not on 12s with that wind, that might be part of the problem.

Also, just for perspective, the power to weight of the 60" class planes is very hard to duplicate... So the lack of the jump into the air might also be a product of the plane literally being more than twice as heavy as the MXS.... Yet you're really only adding about 1000w.

4315 on MXS puts out 1600-1700w (or at least mine did) where as the 4330 is in the 2700+ range).

 

[3dNater]

Good insight... it will not feel as punchy. A video is worth a thousand words 30 times/second though

 

[AKfreak]

Yes I am in 12S. I need to get a new analyzer. I was told it would be around 3200 watts with my current setup. The motor power, motor, prop combo was chosen specifically to give me the same performance on the Extra as my MXS. I spoke to Ken extensively before I ordered anything. The purchase was for an 11lb 75" 3D monster with extreme burst power. My Extra is less than 11lbs. Here is exactly what Ken said before I bought anything, "The 216Kv on 12s with a 20x8 prop pulls about 3200 watts for instance and is what I would recommend if you want the same power to weight ratio as the 64. It can handle 3200 watts because the amps are only 72 max, but your average amp draw will probably be around 35 or 40. Ken Young"

I will just have to fly this thing and see. Don't get me wrong, this setup has unreal power.. Scary power in fact. It's just kind of lazy in getting there, there is a lag (sloppiness) that I am not used to in an electric plane. When I roll on the power slowly to full throttle, the horizontal stab presses extremely hard into my calf. More so that any other plane I own. Not sure how much force it's generating, but it is a ton. I just wish it was instantaneous when I hit the stick.

 

[3dNater]

:needpics:

 

[AKfreak]

Sorry but how do pics help this situation? Just sayin.

Humor me for a sec.. imagine you watched a video that shows you exactly what I am saying to be true. How does this help determine the problem?

I am off to make this video. See you in a bit.

 

[Enterprise]

A question on the, "Throttle Cut". I do not have that on any of my electric planes. Is that necessary, I assume that is a safety feature that I might need to reconsider. Besides safety, is there any other benefit to a throttle cut on an airplane?

If not, just do a throttle to throttle mix. This is what I do for a idle down on my gassers. I have not had a electric yet that needed the idle up deal, but whenever Tyler or Cody fly my planes they trim up the the throttle channel to do this.

I just got a Gecko 155A for my A60-6XS and I was going to look at what options the PC opened up. 28 pole motors have some different issues from the 14 pole Motrolfly's. I never had to do anything on them, but the biggest one I have had was a 4325-310.

 

[AKfreak]

So the PC does open up more programming options? Do you have a link for the ZTW software? I just know somthing is up.. I am uploading the video now. BTW, I didn't even come close to predicted 3200 watts which is a little disappointing. My packs were fully charged (50 volts) and I hit 2800 watts. You can see above that I was told that with a 20x8 I would see 3200 watts. 400 watts is a lot of power if you ask me.

In 4 mins the video below will be fully uploaded. I hope it helps you guys see what I am sealing with. Meanwhile I will try to find the ZTW software to see if I can make any real changes to the ESC setup (it really feels like a soft start up). But what the heck do I know, I am just a newb...

[video=youtube_share;rKthYmWHutE]http://youtu.be/rKthYmWHutE[/video]


Edit here is the ZTW software link

 

[gyro]

So the PC does open up more programming options? Do you have a link for the ZTW software? I just know somthing is up.. I am uploading the video now. BTW, I didn't even come close to predicted 3200 watts which is a little disappointing. My packs were fully charged (50 volts) and I hit 3800 watts. You can see above that I was told that with a 20x8 I would see 3200 watts. 400 watts is a lot of power if you ask me.

In 4 mins the video below will be fully uploaded. I hope it helps you guys see what I am sealing with. Meanwhile I will try to find the ZTW software to see if I can make any real changes to the ESC setup (it really feels like a soft start up). But what the heck do I know, I am just a newb...

[video=youtube_share;rKthYmWHutE]http://youtu.be/rKthYmWHutE[/video]

what your video showed me, is that everything is normal. Especially at 2:32, where you start pulsing it a little while it's spun up a some (similar to what you'll experience IN FLIGHT), and the response was aggressive and instantaneous, and again around the 2:49 mark. I think it's unrealistic to expect the throttle to spin up any more aggressively from ZERO power when you're only give it a quarter second pulse (earlier in the video).

I think your analysis of the throttle response is a little off.... especially since you haven't flown with it. Very hard to make a judgement about how it will perform in flight during static run-up bursts.

Also, I couldn't see what your amps went up to, and what voltage dropped to under load... the watt meter fell. The cells ability to maintain voltage under load will determine your power output. Are they new packs? How many C rating?

Sorry to disagree with you... please don't take it the wrong way!

 

[Enterprise]

At full throttle what is the voltage sagging to? You can plug that into the prop engine to see what it tells you for watts in. I know when I had a A60-5S, I was using weak batteries, and that was most of my issue with getting power out of it. In the castle I could change a setting to get better throttle response. Man, I wish I was home so I could play with my 155A to help you out. The program won't seem to let me into demo mode to play with the settings.

 

[AKfreak]

I just went through the PC set up menu, and there is noting different that what you can do with the little LCD programmer. Can the timing set to, "Auto" be the culprit of the slow throttle response?. I am gong to contact Ken to see what timing he recommends and see if using the exact timing makes a change to the response.

As to my packs, they are brand new (3-5 cycles max) and run the hell out of my MSX. The SAG at WOT is from 49.5 volts to 45.32 volts. That is a lot of sag? That definitely shows why I don't see 3200 watts. However, that sag shouldn't have much impact on the initial throttle response.

How much sag do you see at WOT on your packs? Also don't know how to use, "Prop Engine" so I guess I better learn.