This is a separate thread dedicated to 72 124 waterproof motor.
72 124 Motor specs:
Kv - 110
Continuous Current tested: 140A @ 16S (probably can go higher)
You can grab one from me for 250 EUR + Shipping of your choice.
Hi, Sounds really interesting! Do you have a Metr stat? What is the weight of this motor and where are you located?
I do not have a Metr. But I have this video from last weekend and I’ll make some VESC sweep’s and post some graph’s…
I’m thinking about increasing Kv to 110. Please post your thoughts on optimal Kv!
90x16/12= 120kv for most prop out there and 12s battery should be nice
The 63100 motor is really efficient and powerfull with 140kv. I would go for 140kv
The FR motor is 130kv so I’d say edge it out at 135-140
Why go above FR kv ? I don’t know many people using FR Motor full throttle , this means high top speed , high amp , high quality , or lower pitch 2 blades prop … no towing …
But I might be wrong …
I am intrested as you already know😉
Kv 110 or 120 if possible for me👌
Because it makes no sense to put out a motor that’s similar to everything else on the market already (100kv - 130kv). However it makes sense to improve upon it. I’ve used the FR motor full throttle a lot at 12S. It would be good to have a slightly faster alternative for 12S as most of the cheaper VESC’s can only go to 12S.
But this will increase current… no? Which VESC for example you will propose for 12s?
Kv is only a matter of torque at the end. If for exemple the FR motor has 130kv and a torque of X Nm he will have a prop slip of something predictable with a certain prop at a certain speed.
If you then come with a 100kv motor and higher torque say Y, you have a lower prop slip with the same prop, which means you might end up with higher shaft speed and you also can use bigger props which are more efficient.
It makes sense , higher nb poles , lower price than the 61151/2
It doesn’t make sense to have a higher kv motor with a lower torque ( power would go in amp and heat not Voltage:rpm )
my thought process is closer to @Alexandre, with one less turn we end up on 110 Kv so that’s what I’m going with. 12S with a slightly larger prop will be just fine. And 16S can use much smaller props for lower consumption.
Prop slip has absolutely nothing to do with motor torque.
You have to have prop slip in order to generate thrust and the slip will be proportional to the amount of thrust required to drive the foil. Therefore for foils there is a very low amount of slip. The more efficient your foil, the less slip you will see.
If it results in an actual 110Kv, then it will be pretty close to the 65161 120 kv motor that only spins in reality at 110KV. That would be a pretty interesting comparison though!
I never said you don’t need slip. Read me carefully. I said you will have a lower prop slip with higher torque. And what about following correlation ? :
Torque slip is completely different to prop slip.
I think what @Sliman_O means is rpm drop under load. A motor with X torque will drop less in rpm than a motor with < X torque. Lower rpm has the same effect as propslip if you look at top speed. But you are right, propslip and rpm drop is not the same and torque has nothing to do wth prop slip 
Yeah, ultimately there’s a tradeoff. Lower KV, more torque, but then you need a higher pitch prop to get to the same speed. A higher pitch prop in turn means more amps. So you ultimately end up in the same area.
The alternative…a higher speed motor with lower pitch prop…
Considering the best prop we have thus far (and probably for a while still) is the FR 6" pitch and we already have it working well with 100Kv, 120Kv and 130kv. The logical next step is to make a 140Kv and try it on that and see if it can do even better.
