We hobiba declare new efoil motors options available to deversify the efoil future:
Shanghai Boat Show 2024 (Mar 26 to Mar 29), Hobiba launched 3 new products
Not only D65 and D70 for efoil, people deserve more motor solutions, like D57, D47, even D37, and even advanced motor tech, like the rim drive thruster from Hobiba
Can you share the motor specs for the different variants? Are any of them proven to work in an efoil drive, any test data is interesting!
Sorry, these models are under modification with business clients right now, thanks
And your back again with your confusing posts. 
Hey everybody on the primarily DIY forum - look at these cool new motors!!! BTW dont ask me any questions as I only provide other information to other business owners.
Hailin if you have a good solution for us in a jet drive or rim drive I think you could move some units here and get some good feedback.
I recently purchased a D70L165 (120kv) waterproof motor from them directly… so far I’m impressed and they do have specs on their website for the motors they sell… very detailed, more detail than most of the other main motor sellers direct from China. Here is a link to their home page if you want to see more specs: https://en.hobiba.cn One word of caution, they are getting in to the ESC market and are having some technical issues with those still while they finish development. But the D70L165 motor has been solid for me so far, amazing actually!
But you say limited to 100amps ??
I’m new to this forum. My apologies, if warranted, for reviving an old post.
I have a foiling catamaran project that drag testing and engineering studies indicate could be adequately, near optimally in fact, powered by the Hobiba DL70L165 kv=78 (2 of). I’ve not found anything similar with such a low speed constant. I’d like 60 or so - but 78 is pretty good.
You indicated, @FoilerJ, a couple of years ago that you were very happy with the motor. Could you update your experience? Any recommendations for any other low kv motors with continuous power rating >=3kW. What ESC are you using - is it worth considering Hobiba ESC yet?
Have you checked out Flipsky offerings?
@MoretonBayKiting I’m still using the motor and it works great! I ordered another motor from them a year or so later and they were able to customize it for me too so you might be able to reach out and get a motor at the exact KV you’re looking for. Since I’m just a hobbyist I haven’t used them since but hopefully they are still doing well and can help you. They were great to work with!
I will second Foilguy in that Flipsky also has some decent motors and if you get them on sale there can be some good value there (I have several of their 6384 motors, and a couple of the smaller 5080s). I think they can also make you a custom KV motor if you talk to them but anything custom usually takes time because they need to get it in que for a build.
As for ESCs I’ve used Maytech 300A, SeaKing 300A, and Flycolor. I’ve only lost one ESC and that was due to using lower quality batteries on a fairly powerful motor that had too much voltage sag / ripple and stressed the capacitors to the point of explosion (it was a fun experience ;). My only advice is to look at the continuous current ratting of any ESC, and subtract at least 20% from that and you should be fine. Also don’t skimp on the batteries… I started out with 6s 9000mah Zeee batteries and they worked okay for the DL70 (I used 8 total, 4 in series, then 4 parallel) but the internal resistance of these batteries is fairly high and unless you run conservative on the throttle, you’re stressing the caps, even with extra Cap Packs which I do use. When I moved up to my DL85 motor they just couldn’t handle the power (even though on paper it should have been no problem). Now I use SRD-V4 22.2V-6300mAh-250C Speedrun packs and they have very low internal resistance and I have not had the sag issue. I now run only 4 total (2 series sets) so my setup is lighter and no noticeable sag as the packs run down. I still get a 35-40 minute runtime but that is on foil, so less drag than your catamaran. You will probably also have more room to store batteries on your catamaran so weight will be less of an issue I’m sure.
My only other advice is to use QS-8 Anti-Spark connectors on everything except the final motor connection from the ESC. They are solid and built to handle a lot of current. I started out using EC5 (that was the largest connector I could get on Zeee packs at the time) but they are just not large enough to not cause resistance. They did work fine with the DL70, but it’s not worth the savings. QS-8 is probably overkill but on most these setup the battery is not necessary right next to the ESC so 6 Gauge high strand count wire and QS-8 allows for longer batter runs and minimal resistance / voltage drop.
Hopefully something here is useful and I wish you well on your project! I have since made 3 motorized fins for sups (smaller motors), along with several eFoil systems and all but the DL85 motor worked fine with a 300A ESC. Just make sure you can keep them cool. (I use a closed loop cooling system with external aluminum radiator blocks.)
Thanks very much FoilerJ and FoilGuy. I’ve had about 15 messages back and forth with Flipsky asking about winding to lower kv - all the replies recommended different stock options at 120kv or higher. Hobiba sent a complete and very useful reply with 3 options that all look close to what I need. Given your positive experience with Hobiba, @FoilerJ, I’ll try some of theirs.
The battery design is not well progressed - I expect I’ll run 2 quite separate systems, with integrated control, with perhaps 3kWh LFP @48v per motor. I’ll target current at <1C at cruising load. I hadn’t factored the extra 60kg or so into the thrust estimate. 200N per system is based on empirical drag testing. But that was with different foils that I think will transpire to be less efficient than the new ones - hopefully the new foils will compensate for the extra load (all up weight, including 2 crew & 60kg batteries, will be about 370kg).
Noted re connectors and cooling ESCs. Vessel trim will be OK with batteries at the stern and both crew forward. Cable run from battery to ESC should therefore be very short.
