Hi guys,
can someone help me to figure out whats the best solution?
I want to build a kajak boat with two motors and want to use 65162 motors. Which kv is best and why? There are 100, 120 and 195 kv available.
Thanks!
Usually a kajak will reach max speed with only a few horsepower engine, just curious, why would you need more than one 65162 motor for it?
want to tow a wakeboarder, therefore extra power
OK, what speed are you looking for?
if you want to tow a wakeboard then you need some more power… so motor like Jell Motor or 81… outrunner…
I dont know,
have to see whats possible
ordered 2x 65161 + 2x esc + remote
thanks,
can you please be more specific? what motor do you mean exactly?
Don’t know much about wake boarding, but on the videos look like they are towed rather fast, not sure a Kayak can move fast enough? Or is it a board on a foil?
just wakeboard, no foil
pulled on a kayak
tow speed around 20-30 kmh
Do you have a picture of the kayak, so many variants with very different properties and speed range?
Sure, its this one:
https://s.eticaretbox.com/1650/pictures/201535112635_07.bic_ouassou.jpg
Called Bic Ouassou
If needed, I can buy any other boat or kayak 
Might not be the most promising concept to tow a wakeboard with an electrical canoe. You need to move both the canoe with a pilot plus the wakeboard. The wakeboard has a lot of drag, especially for takoff, as it does not float much. With an unmanned tow buggy XL you could avoid the pilot of the canoe. Still needs lot of power. Easier to use a boat.
The challenge her is that you have to reach planning speed not only for they kayak but also for the wake board. With roughly 2 x 6000 w you also need pretty big battery adding weight. Looking at the hull shape of this Kayak, it look like it actually might reach planning speed(the opposite to most models), but is it optimal or would this still be possible to use as intended here, very difficult to say.
You need torque so would go for a low pitch propeller. You have much different requirement here than the for the foils, actually the Yamaha clone propeller with 5 pitch might work in this application, would start with uncut version. With 120KV and 48 V should end up in the required speed range, but as load is heavy, might be hard on motor and ESC.
A inflatable V bottom boat with 10-15 hp outboard would probably be the easiest way but too late now:)
Hm, maybe I remote control the kayak (so there is no added weight for a driver + more room for batteries) and just use a remote controller while wakeboarding. (have to add steering)
Dont know if this jet propeller 120mm is better?
https://de.aliexpress.com/item/4001293682586.html?spm=a2g0x.12010612.8148356.1.79ff1456yCGMEe
Bottom of kayak looks like this:
https://a0.amlimg.com/NTdlMDkzNjkyMTg4ZmNhOGUwOTIzZmMzYjljOTZhN2JxG5I1tjJAtvmer245pvI2aHR0cDovL21lZGlhLmFkc2ltZy5jb20vNTBmNjJjZWNmODUwNzEwOThiYTRlZTAxZWIzNjY3OGZmNzhhNWIyNWY4YzMwZTE3NTFlMTFhZDg4MjA3ODkyNS5qcGd8fHx8fHw3MDB4NTI1fGh0dHA6Ly93d3cuYWR2ZXJ0cy5pZS9zdGF0aWMvaS93YXRlcm1hcmsucG5nfHx8.jpg
Concerning the battery: I already have 16 of these (4 packs each 4):
https://de.aliexpress.com/item/1005001716510156.html?spm=a2g0s.9042311.0.0.27424c4dBmQ1To
which estimates around 51,2v 200Ah or 25,6v 400Ah
(~10kWh)
Use the 65161 inrunner and a prop instead and save cash and 2x efficiency. 120mm will need +10kw to work with high effiency and your fun will be over in 5mins with that battery size.
What do you mean with “over in 5 mins”? The battery is huge.
Look at it, its 16x 3,2v 200Ah, so 10kWh
That means, I can run on 10KW for a full hour. Thats massive. It can flatout run one hour at full throttle (assumed 100 % power equals 10KW)
Sure 10kwh low power density cells and 80kgs extra to carry into a kayak each time.
Trust me, larger jets are OK in jetskis. In these applications petrol engines are superior in range/price/weight.
I’ve had a Tesla for 6Y, if I had to take the battery out and carry it home after each ride it I would still be a petrolhead.
5min was maybe not meant literally, but the point was that in your application propellers work much more efficiency than jets. Only at higher speeds the gap is getting narrower.
On the flipsky 65161, is the stock wiring fully waterproofed where it enters the motor?
it should be because manufacturer says its
Waterproof level:IP68