For my first 3sk8 proto three years ago, I scavenged parts from a weird Chinese toy called the Speed-go that only had two wheels. It was nearly impossible to ride but an interesting idea. I have also seen you tube video that I can’t currently find of a two-wheel board made by a guy in Israel. It looked like it performed really well, but it was highly engineered. Not really my style.
You certainly can run two of these on 12s. They have a running current of 50-60A. BUT it isn’t considered best practice and will shorten the live of your entire electrical system. There are other wheels out there that would work wonderfully with a 12s system.
@Skunk It just does. Magical geometry makes it happen. If you could ride my boards, you would see what I mean. Everybody asks the same question. Then they ride and realize that it turns better than their 4-wheeler.
The AT board is a little different from my street board. It might take a few prototypes to get the geometry just right.
Yeah, the trucks and suspension would have to be full custom. There might be a better wheel for his application. Regardless, I love his instagram. Damn fine DIY.
So the spec list of this motor shows 11~ nm of torque, by gearing the normal Mountain Board Choice Outrunners like 6374’s you’d be comfortably over that.
I suppose the implication is that the single direct drive wheel/Hub is less parts to be concerned about, gears and belts and what not. Do we think that something like this would be capable of holding the traction and putting the torque down to pull that front end up?
We’ll see in about a month I think the specs on Alibaba might be a little goofy. My street motor is 48v 1000 watt, and they list it with the same torque rating. It climbs like a beast for a street board. The 60v 1600 watt motor should rip.
Also, your right about the simplicity of the system. One motor and one ESC. The back end is neat and tidy. Also, it’s very durable. Very.
Whats ironic is that this would take me about a month to fab up myself as well, assuming I had no other projects. Whats unfortunate is I really want to know how well this works because once I get the simple MBS Atom90 board done, its going to a buddy of mine and I want to start working on a personal build that can easily keep pace.
Suppose innovation takes time maybe ill wait for @shaman’s serious FOCer to come out before I look at a 60V motor.
@Davewesh If you need help with a board or motor mounts, give me a shout. I actually don’t bother with FOC on the three-wheelers. They’re already more efficient than four-wheelers and the big wheel doesn’t have the same start-up and stopping issues that small ones do. At the end of the day FOC just seemed kind of week to me. I might just need to play with it more. I could be wrong.
I dont actually know if I would or wouldn’t use FOC on the 3SK8
FOC or at least Hybrid mode for FOC-Low and BLDC-High would be ideal. The Serious FOCer is mostly called out due to my belief and support for Shaman’s work. That said, its also got several of the features one would want on something like this. 84V Max, and the amps to go with it, stronger DRV, etc, etc. The problem is that its going to require all new firmware from what I am seeing due to the use of a completely different DRV (not 8301/2) which means its likely not going to be out before it starts to snow in my area.
As for the motor mounts, based on what i can gather on the screenshots looks like you used a U shape motor mount for the rigidity and put some trusses/flanges on the ends to mate the axle to the mount.
This brings up a thought though. I wonder if one could make a Swing-Arm of sorts for something like this. And use a small loaded shock/spring to add some suspension travel. I would be concerned about several other things in that scenario - like height and board pitch from front to back… I might design that over the next few weeks and see what it looks like in fusion 360.
I’m excited to see your result. Keeping things simple might be best though
To mount the motor I made brackets using 1 1/2" by 1 1/2" angle-iron that can be found at any hardware store. The hitch is that you have to weld the axle washers to the bracket in stead of using the groove-lock method that was intended. If you don’t do that your axles will break free and rip the motor cable out. Ultimately fucking up a lot of expensive stuff in the process.
Imma check out this Serious FOCer. I love supporting the work of people on the forums. The 16s ESV by Team Tri-force looks like it might work really well for this. Hopefully, I’ll have it by the end of the month. It’s supposed to work pretty straight- forward with VESC firmware. I’m really excited about this board.
Here’s a quick update on the 3SK8 MTN board. I received the 16s 200A ESC form Team Triforce UK. It’s a sharp lookin’ esc. I’m excited to put it to work. The three XT90 battery plugs would be a bonus for anybody using RC lipos. It’s worth mentioning that even though this is a single motor build, the esc is a dual-esc. I’m doing a rebuild the deck using my new CNC router. The new version will be reinforced with heavier weight fiberglass cloth. This will stiffen it up a bit, because it was a little too rubbery.
I bought a spot-welder and decided that my first battery build will be for this thing. I’m going to make a 16s4p battery with some fancy 18650 cells. I haven’t decided which ones yet. Also, I had considered making a custom enclosure of some sort but then decided that a pelican case would work just fine.
And I included a sneak-peak of the 2.0 model of my Firefly/Feather smart remote build. The enclosure is CNC milled and the screen is upgraded form .96" to 1.3". I’ll be starting preorders for a batch within a month. If you’re interested, keep an eye out on the forum and my site www.3sk8esk8.com.
I think the specs on Alibaba might be a little goofy. My street motor is 48v 1000 watt, and they list it with the same torque rating. It climbs like a beast for a street board. The 60v 1600 watt motor should rip.
maybe ill wait for 