Electric Jet Surf Board

[Pompel]

Hi
I have plans to create an Electric jet surfboard and need some advice from you experts.
I will be using this jet drive:

http://www.mhz-powerboats.com/Jet/Jet-62.html

It is the same used in these surfboards:

https://www.youtube.com/watch?v=d6G6XkyBAxY

The jet drive is working best around 16000rpm. Need tips and advice for selecting motor, esc and size of the battery pack.

[NativePaul]

I haven't used one, but I may be able to give you some idea with a little basic maths.

Assuming you want to keep it to 50V or 12S for safety the 12KW it suggests is 240A, I don't know if jets have as big peaks as props do but I would go 300A+ for an ESC.

At 240A most motors wont produce their stated KV, I would go for 380KV, which is around 19,000RPM unloaded, and should be around 16,000 under load.

If you want it for more than a quick burst to get you up on a wave you will need a lot of battery, at 240A a 1 min run will take a 5000mAh battery down to 20%, they say up to 40 mins runtime which I would suspect includes a lot of partial throttle use that is incalculable, but if you wanted 20 mins at full throttle for example, you would need 100Ah of LiPo battery (12s20p of the popular 5000mAh cells) Another way to go would be to use LiFePo4cells which have a lower voltage, but have a longer cyclic life so wont need replacing so often, the capacities needed will be the same, but you would need 14s to get up to the same 50V.

[RunningBeer]

Hiya, I have a swashdrive jet (56mm impellor also designed for about 16000RPM) running on a 10S system. The motor is a 480KV Neu22153Y. This gives me @17500 RPM unloaded. It draws a peak of about 90 amps when running, and runs pretty cool. I have a castle HV 240 amp controller. This boat is 10 years old and has never broken down. Dunno about the sea though, she's too precious for that kind of thing.haha.
Cheers RB