Testing the towing capabilities of the electric water-jet surfboard. Running around 15kw electrical power from battery for this test.

Location: Botany Bay/Cronulla Beach, Sydney, Australia. Riding a 1998 SeaDoo XPL, powered by the Rotax 950cc 2 stroke, 2 cylinder engine. The engine in my ski is running SBT pistons at 1.0mm overbore and SBT carb parts.

A project I have been designing and improving for the last few months! Inspiration for performance requirements was taken from SeaDoo's 2 stroke Jet Ski's. An electrical power of 18000w or 24hp is drawn from the 4kWh/25kg of batteries. An estimated 13000w, or 17.5hp (horsepower) is mechanically delivered to the Water Jet Pump via the brushless electric motor that weighs in at under 5kg. The Jet Pump unit in the board is built from a combination of machined and laser cut aluminium. As well as PETG 3d printed components that are sanded smooth for better efficiency. The intake duct for the jet being the largest 3d printed component. All printed components were printed on a Creality CR-10 3d printer.

Custom designed electric water-jet pump on a fibreglass laminated foam core board.

Some VESC data in sync with 16S full speed run, good thing there wasn't more damage as a result of the crash.

Top speed run on the efoil with 16S! The VESC motor current limit was set at 255 amps. Prop was turning at roughly 4800rpm. - 16S11P samsung 25r 18650 battery pack, bypassed BMS so is only used for charging. - SSS56104 500KV motor - Neugart PLE040 5:1 gearbox - VESC 75/300ESC - Slingshot Infinity 76 surf foil - Custom board - Maytech remote - custom aluminium prop, no duct

Some efoil footage from late 2019 🤙

Pushing the 26 year old SeaDoo to its limit!!

Propulsion system statistics of the DIY efoil. At full throttle the motor is doing 20,000 rpm, that's 333 turns per second! Motor rpm is reduced with a planetary gearbox down to 4000rpm for the propeller, while the torque output is around 9.5nm at full speed. The prop torque can go up to 11.25n.m while rpm can go up to 5000 (25000 rpm, 2.25nm at motor) more speed is possible with a higher voltage battery!

Getting some airtime

This vid shows the top speed: https://www.youtube.com/watch?v=gzhQLi79nSc

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Improving and testing the prototype. *V2.0 will have a higher top speed: over 40Kph* *Current top speed is 33Kph - not fast enough* Music: |Scrape the sky - can't stop won't stop|

Testing the eFoil prototype! Get around it!

Testing DIY direct drive foil in the lake.

Cyclone 3000W Mid Drive motor with reinforced motor mount on 2010 giant glory 00 DH bike. 40a @ 75v

Insane DIY Mid Drive E-bike | 3000W | Cyclone Motor 2010 Giant glory 01.

Most powerful motors I have ever used, 2.5 min of hard flying max out of a 65c graphene 4s.