Two motors? From X4

Which 2 batteries where you using?

Current setup is with the Tattu HV 25ah. 22lbs all in including batteries (excluding harness).

Okay. My thought was having a single mad M40 50kv motor (6 lbs), 47-51 inch prop (~1 lb), 24s 300a capable BMS (1 lb), battery container (~ 2lbs), a light weight 18s esc (sub 1 lb), and 12 ish lbs of samsung q30 or equivalent li-ion batteries in an 18s configuration.

The total weight without a harness or cage of any sort it would be about 23 pounds. The battery could hold up to about 1.35Kw or roughly 20% more power than 2x Tattu hv 25ah batteries. Also the M40 should be more efficient than an M30.

There’s also about 6-7lbs for the mounting system, CF tube, CF plate, wires, etc. You’re setup will likely be 30lbs when done. Also 47-51 inch prop is very big for a hang glider, too big for me. I cut my keel off for a 34in prop but for a 50" you’ll want limiting lines connecting harness to glider so you don’t hit wing. I have these on my LD Explorer. Not sure li-ion batteries can handle the current required I think the C rating may be too low but others can chime in on that, also what 24s 300amp ESC do you plan to use? I’m guessing that’s not cheap. With that setup you are sacrificing handling for efficiency and adding 8 more pounds which is noticeable in flight. My goal is to climb to a thermal; on a good day you could launch when i nice cloud is near then thermal out for a long flight.

Anyway if you build it please share results and cost. My setup is about $2,500.

That guy never gained one foot hight above his launch level
he only had enough thrust to keep level flight and may be he was also helped by rising hot air from desert

Wow great information! cwallen93117 and Bob27 thank you very much. I don’t have much experience with electric motors and my understanding is very basic. I would like to build a foot launch powered hang gliding unit with at least 50 kg of thrust for an easy take off. I would like to have maximum efficiency so I can have more cruise time under power. I am not worried about the torque. I flew a mosquito harness and the torque did not bother me. I am thinking of a scalable solution so I can fly with either 2 or 4 batteries.

The advantage of using M30 is that I do have 2 Bonka (7S) batteries and I experimented with this voltage on my X4 unit. The disadvantage is that I have to run a smaller prop (34-36") and loose efficiency. With M40 I can probably drive a 49" prop but I am worried about the high voltage (24S) and the risk of fire with 4 Bonka (6S) batteries in series.

cwallen93117 I didn’t know Amazon sells Mad motors. Thanks for the suggestion. It looks like even M40 is available on Amazon.

What do you think about this configuration?

I suggest you figure out what ESC you plan to use prior to buying the motor prop etc. MAD doesn’t have an ESC for their M30 or M40 ESC. The MGM might work but haven’t tested. Good luck and keep us posted.

Do you think I can use this ESC for my project?

I would be very careful with that ESC. The MFG site is here: I have twin ESC from APS which is just a rebranded Flier and I’ve had issues so stopped using. You are strapping this stuff to your back I would buy the best quality you can.

This may work: need to check ERPM. Or this:

I would disagree…

I personally have a mad 24s 200a esc. They also make a 18s 300a esc

JK. It’s actually a 22s 300a esc.

I have a bunch of extra esc from APD, they are a little more expensive but use really high quality components and will be good for longevity. But dont buy on ebay just pm me as there are way to many fees, but they are $650 a pc. They are $1100 if you buy anywhere, $650 is actual component cost not even labor cost for assembly or shipping or anything (i paid $730 for 50pc of them, and that was bulk pricing).

This is what i have, you can see specs here

We also did a custom case to pull the max power of of them. you can see that here


Ya MAD does have ESC that they brand (they dont actually manufacture them). We did test them like 4-5 months back and did tear down of them. They were ok quality, the components were not the best. And there was still some desink problems/software, and it was hard to fix because they arent the original manufacture there was very little flexibility. And the cost is like the same as APD offerings.

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But i have a bunch extra motors and esc that just didnt make the cut for the SP140. I dont have any use for them other then making and over powered ebike or some kind of electric tank, so if you guys are looking for stuff pm me and i can see if i have something that can work for your project. Stuff not cheap and adds up so im happy to give a deal on them, so i can try and recover some of the cost.

Or if you need battery making supply or cells, i got every thing you could need to make a pack of any size.

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I have the Cells, if you have a case, BMS, cell tabs and some heat shrink and a connector to build a pack for the SP140 Let me know how much, you can ship with the SP140 I have on order.

Q: max amp draw so I can size the pack accordingly. I might decide to build a slightly smaller pack to make it lighter.

hello, just a well-intentioned note: about mgm you posted a link to an rc esc. this is only approved for rc. for eppg there is the industry esc “hbc series”. the connections etc are larger then designed for the services provided by eppg as well as other components etc. & pro tool software.

That 300 amp ESC is mislabeled. Below is the email from MAD.

Hi Charles,

This 300A esc is labeled 300A by mistake, but actually its continous current is less than 200A. In your project, you can’t use it. I’m sorry about that.

Address:No. 319, Lianhexi 2nd Road, Xiaolan Ind. Zone, Nanchang City, Jiangxi Province, China
Wechat: 191 7912 0542

Many of the ESCs are only approved for RC except for the Chinese MFG’s who likely aren’t afraid of legal recourse. As a data point the hobbywing ESC on the x4 is for RC, not paramotors.