So today we finally managed to do the maiden of our jet-driven eFoil.
Setup:
Fliteboard Pro
Gong V3 mast with our new V3 Gong <> Fliteboard adapter (more info soon)
Old Gong wing (forgot the size, will update later)
Flipsky 75200 VESC
Battery: 16S12P
Manta remote
JetWave motor (no data available, but from our calculations/measurements itâs a 270KV motor with 16 poles / 8 pairs)
JetWave jet (not like all the others! Itâs a real jet, not a ducted fan)
Since the JetWave batteries are 12S, we needed to set the ERPM lower. Itâs still way too high as the jet starts making foam about 1/2 way throttle
Itâs also way too powerful at the lower part of the RPM range, so weâll need to adjust some settings in the remote/VESC.
As it was getting late, we didnât have time to take any measurements.
Iâll update this thread as soon as we have more data.
One more thing. The plan is to get rid of the backpart of the fuselage, and connect the stab to the jet
Wow, as always very nice and very clean work @Kian! Did you just order the motor and jet directly from jet wave? Curious what the efficiency looks like.
@windego
During testing, we needed to run just the motor.
On 12S, not limited, it reached just under 12,000 RPM. Wow⊠what a sound!
It was almost scary, but in the water itâs nice and quiet.
Weâre now trying to find the correct eRPM for this setup (16S) and still need to do a lot of tuning!
And yes, lots of power, but due to too many RPMs and a very sensitive trigger, itâs too easy to overpower, causing the jet to start making foam (needs tuning)
@S_Roger
We live about half an hourâs drive from the European distributor, but unfortunately they donât want to sell to DIYâers. Maybe itâs because the motors/jets are hard to get (being a new company?).
We managed to get hold of a jet/motor by going a different route (through a dealer far away). Not sure if weâll be able to do that again.
Weâll definitely upload some videos once weâve got things dialed in!
Iâm sure you have likely already considered modifying throttle curve and other parameters on the Manta - there are a bunch of things on the new VX5 that might help.
Canât wait to see this in action - mount it on that monofoil and it will truly be Frank!
You are correct about the profile settings in the Manta, and we are staying away from the VX5 for now, as we already have enough remotes here (by the way, itâs not as good as you think it is!).
The jet generates so much power at the lower end that the mono wing might not be usable, since itâs more pitch sensitive than a wing with a stabilizer.
Maybe after some tuning it will become more controllable, and who knows, we might give the mono wing a try.
Awesome job @Kian . I still have no data for you regarding the amps from battery, personal circumstances are pretty harsh atm:( massive lack of time.
Beware you might experience some unexpected ânoiseâ while actually riding the board. A âscreechingâ or âhowlingâ sound may appear when playing with throttle or during turns/ changing altitude etc. Itâs intermittent and might not manifest at all in your case. I could reproduce this on 3 different masts of Jetwave. Of course Jetwave folks had never heard of the issue (wowâŠeven when not testing or beta testing something i seem to be a shitmagnet for ânewâ issues lol)âŠbut finally acknowledged that it is an issue and they claim itâs related to the nozzle. However i tried 4 different nozzles which was no cure. They shipped me 2 other nozzles to try which i only received today. Iâm sceptical how this will cure it although i hope it will.
I donât buy this, the motor is a 6kw motor so no different compared to the normal motor you see here. With the higher pole count it will just have similar torque to a Lift motor. But a prop is more efficient than any jet so this will always come second to a prop on the same motor.
We are still tinkering with the settings, and at the moment (without the throttle curve set correctly) the jet suddenly âbitesâ and generates a lot of power.
Adjusting the throttle expo settings will definitely fix this.
Yes, a prop is definitely more efficient and superior to a jet, but that is not the reason why we made this setup. Itâs for safety as the person who it is for would like to get his kids efoiling too.
And the âitâs not as goodâ comment was aimed at Foilguy (just teasing him). He tested a lot of the remotes here and really loves the Manta (and the FeRo), but since itâs way overpriced, he went for what he considers the second-best option, believing itâs much better than the Manta.
I did get the joke . However I have never used the Manta or any other remote other than the VX3 (original) and now the VX5 which imo is better than the VX3. I was thinking that the âgearâ function of the VX5 might be useful in smoothing out the startup issues.I also donât want to hyjack the thread with remote comparisons
It was around 38 km/h, but that was while lying down, not at WOT, and touching water all the time. (By the way, itâs quite hard to keep the board down on the water in that position.)
This weekend weâll try to do some proper testing with a few friends.
(by the way, itâs not as good as you think it is!).