Efoil Vibe

[PonoBill]

Sure. As lithium batteries discharge the voltage drops, so the power available drops. It's not huge--depending on chemistry the voltage might be 4.2V at full charge and 3.9V at full discharge, but it's not constant. Multiply that by the series configuration and it's a bigger deal. For a 12s, nominal 48V battery that's 50.4V at full charge and 46.8V at discharge. From a power standpoint if that's at a constant 50 amp discharge (not likely) that's 2520 watts (3.4hp) at full charge and 2350 watts (3.1hp) at full discharge. Not huge, but it makes a difference, and the actual current discharge rate drops with the voltage droop so it's even bigger.

More sophisticated control systems compensate for it, but that's a lot to expect from V0.9 toys.

[surfcowboy]

Weight is def an issue. After having one to use for a couple of weeks I have to say that if I didn’t live inland or didn’t have a dock to keep the efoil on I probably wouldn’t want to own one long term.

Transport, setup, in and out of a beach break all contribute to this. There’s also the weird disconnect from being powered that is different from surfing and even winging. There’s something to the natural energy.

But they should replace all jet skis imho. And they are better than not being in the water. I’m interested to see how towing and distance work to make them more interesting and the social element (like motorcycles) is compelling. way more fun in a group. I’m sure it’ll grow on me as I get more comfortable as well.

Waydoo guys, have you felt them more prone to porpoise? I had an issue with that the one time I rode one. Wondering if it was small wing. Also might’ve been me. I’m no master foiler. Need to try that one again.

Evan, learn to tow your buddies. That’s super fun and makes more foilers.

[Califoilia]

Transport, setup, in and out of a beach break all contribute to this. There’s also the weird disconnect from being powered that is different from surfing and even winging. There’s something to the natural energy.

^^^ This ^^^

I've had my Waydoo for 3 weeks now, and all my buddies can't understand why it's still not got it wet. But the above is exactly why I've not been in any hurry to do so. I love surf foiling, and there's not been a day where it's been flat w/o any waves for me to jump on when I'm at the beach...and I don't see anytime in the near future that that'll change much at all.

Waydoo guys, have you felt them more prone to porpoise? I had an issue with that the one time I rode one. Wondering if it was small wing. Also might’ve been me. I’m no master foiler. Need to try that one again.

Think it might be you, because the one time I rode my buddy's Waydoo (w/ small wing) I didn't notice that at all. But I also outweigh you by probably 40+ lbs...so throw a 40 lb backpack on your next time out with it, and see if that helps.

[PonoBill]

I expect my ridiculously heavy efoil will wind up being 90 percent tow vehicle, but not with me on it--with me behind it. I set up a tow rope with a 4-foot section of PVC pipe attached to the efoil to allow the rider behind it to steer. I can actually turn it by just offsetting my arms. I tried it yesterday and it's very cool. All I had to do was take the foil off the mast and attach the PVC "tiller" and tow rope. the speed control for the takuma/avante actually has about a 50-yard range, so no issues there.

Most of the weight of this thing is in the board itself. the motor, mast, and foil are not very heavy, and the battery is not bad, though it's a good size and gives me about two hours of run time. More than I've actually used. I generally quit with 40 percent left. It's the board with the controller that's stupid heavy.

Pain in the ass as a foil, but super light as a tow vehicle and I don't need a buddy to pull me. Good thing, I'm not that sociable. I'm one of the rare folks that benefit from COVID actually making me seem kind of normal, I can avoid people without obviously being a dick.

[Admin]

That sounds super fun.  I want to try that.  Please make it a whipper inner.  Wear a little beacon that it can follow once you've dropped the rope.  That would be extra sweet.

[PonoBill]

That sounds super fun.  I want to try that.  Please make it a whipper inner.  Wear a little beacon that it can follow once you've dropped the rope.  That would be extra sweet.

Yeah, the tech is actually pretty easy. Cell phone in your pocket, ESP32, GPS and a little modified drone code in the sled. Probably won't be a reliable rig as-is in big surf--they're stable upside down.

[oldfartsuperdad]

On the battery losing power issue - I do notice some fall off in power as it gets low - but not that much.  The biggest drop I notice is operating it when the water temp is 42 deg F and the air temp about the same...Brrr...  Seems like the cold definitely effects the output.  On the porpusing - I'm still getting used to things so not expert enough to say - however, some of the more experienced folks over on the Waydoo users facebook page are already experimenting with shims under the stabilizer and reporting better results at reducing this.  There is a video i saw posted on the page of someone using the foil to tow him into small waves...drops the rope - surfs in - pumps back out to the board and repeats...it looks like hella fun.

[PonoBill]

Good observation, battery droop from discharge is about 10 percent maximum. From cold it can be about 30 percent. And good for you for going out to play in that temperature--I won't be joining you. Since I've lost weight most of my Orca suit is gone. It's 69 degrees in our rental house in SoCal this morning and I'm cold.

Shimming the stabilizer will certainly help porpoising. Just make sure you go the right way. Reducing the incidence angle by shimming the front screw will reduce initial lift but that's no a big issue with these things, you just need to go a little faster. Just like those balsa gliders we had as kids--if the glider porpoised (stalled and recovered, then stalled again) you moved the wing backward which reduced the leverage the fixed stabilizer (elevator) had. Move it too far back and it turns into a lawn dart, which is why I'm not a fan of ultra-short fuselages.

I haven't measured the incidence angle of the Waydo, but my Takuma/Avante benefitted from a little reduced incidence angle. Mine has a huge wing and a short mast which makes stability critical.

[tarquin]

Just had a friend come around to fix an efoil.
 He knows what he is doing. He just wanted to borrow some stuff.
 No wonder these things are heavy. Mostly glass with a very thin layer of cosmetic carbon. Didnt dig deep enough to see if there was foam but lots of glass. The hatch, everything was way over built. No battery or foil on it and it was pretty heavy.
 Water cooled. If you loose power in colder water maybe there is a way too slow or even stop the water cooling.
 Pono, when my brother and I were kids we would drive the dinghy with a PVC tiller attatched to the outboard so we could sit up the front and stop it flipping.
 Maybe just buy a RC boat and modify it.

[PonoBill]

I thought about building a hull until I realized I already had one. If I decide slinging myself into surf is sufficiently fun I'll probably build one to deal with the self-righting problem and to add steering so it can navigate back to me. If an efoil gets flipped before it comes to get you, you could be waiting a long time for it to show up. There are some simple ways to make one self-righting, but it might be easier to just build a hull, especially to include autopilot steering.

The PVC isn't to turn a tiller like your outboard example, it's to turn the whole thing. Slinging out to one side will turn it without a pipe, but with four feet of pipe out the back and the tow line fed through it, I can turn by just switching hands and holding the tow handle off to the side.

[tarquin]

Yes I understood that it just reminded me of those times.
 I am sure you could find a RC boat that you could modify easily.

[tarquin]

You can have 2 lines as well. One to each corner. Pull on the right one and it turns right,etc. Its an old idea but it works.

[PonoBill]

I thought about that but I'd need a fairly wide handle I think. I'll try it though. The PVC pipe method turns a bit slow.