The wettest non-audio build thread

This project has stemmed from my fitness SUP project. I have two vehicles under development now. Being amphibious and while on land, there are Australian rules and vehicle standards to comply with. These will slot under the rules and regulations governing E-bikes. It's a different story and set of rules in the water. Both devices will slot under recreational devices and not require registration if they remain under the 2.9kw power for marine use. The limit for land use 250w. Both vehicles will feature dual power trains

FB is mainly a dry ride vehicle with the rider out of the water at all times. The basis for this is a SUP wearing a gokart type frame suitable for the marine environment. This is getting the cross trainer device that I came up with as well as a 250w motor in the PAS format for a pedelec and a secondary marine drive system attached to the x-trainer

NC is a wet ride with the rider sitting around hip level at rest. I am facing the challenge of applying foils to the FB to balance the wet and dry drive systems to only have the fins on the wheels dipping into the water while underway. The foil challenge for the NC is to acquire enough lift to bring the rider out of the water underway

I'll have some pictures coming up later today with the beginnings of the construction. I have still to sort out the axles for the FB
Be interesting to see the generalized plans or form factor.

Electrical usually assumes direct drive.
But a 2 or 3 speed transmission would help with 250 watt power limit.

3000 watts on a boat is a trolling motor.
Would have to reduce weight and higher speeds
would be a small jet prop
Yes I am considering a small jet or a ducted prop for the marine drive with a 2 to 3kw motor. Form factor for FB is a gokart frame with a smaller SUP body. NC is more like Citycoco E-scooter and mostly relies on the buoyancy from the wheels

A regular mountain bike seems fine on our beaches. I would like both crafts to be on par with the mountain bike on the sand when it comes to speed. Looking at the linked pulley to start off with to get some ideals on ratios!12000029597742279!rec!AU!3392394610!
There is quite a bit of drama regarding the gokart shape for beach use. It seems both Transport QLD and our local council is only comfortable with the bicycle, recumbent trike and personal mobility device form factors. There is quite a bit of resistance to the gokart form factor even if it technically ticks all the boxes for E-bike

I need to dial out more of the amphibious capabilities out of the FB project but the NC project remains unchanged as it actually fits under the personal device form factor. Today has been more redesign on the FB frame and axles including a whole new lot of bearings selections

A conundrum that I am facing regarding the bearings for the FB is a question of cheaper parts and more fabrication (CNC and welding) vs more expensive parts and less fabrication. This includes things like routing out bearing housings in plate ally against using pillow block bearings. More fabrication also has the added plus of being able to control material and weights which cannot be done with more featured parts. Again taking the bearing example, a narrower and thinner high strength bearing can be housed in a machined cavity with oil seals separating housing from axle. Less expensive and lighter than stainless bearings on a stainless pillow block

Tyres for the FB will be under ride on mower type sizing with 16x6.5x8 for the fronts and 22x11x8 for the rears. I will be making the tyres custom for this particular application. Today was also about acquiring the materials for the rims as well as the inner tubes for the custom tyres

Another things fall into place today, I managed to come up with a very workable design for a CV joint/shaft for the rear axle to enable steering on the rear axle as well as allowing things like camber, castor, toe on both axles
Easier to use a bicycle hub motor
and just use a large tire frame style.
and bolt right on

Basically all bolt on and the biggest battery back you can fit

350 watts is pretty normal basic hub motor.
Hilarious that they restrict to 250 watts.

Would just use a everyday 350 watt 36 volt hub motor
And put a big custom professional looking sticker
on the motor that says " 240 watt"
and enjoy life.

Or the motor rating is nonsense
since voltage can be reduced to 250 watt

Only real issue is top speed on public roads.
No cars on the beach
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