Right what in the name of god am I doing wrong here?
I ran one of the FS 75100s on the bench with a different motor. It did this for quite a while too, but for some reason span perfectly fine during motor detection. Got nowhere with it for a while redoing motor detection and triple checking settings, then when I used the VESC tool 3.0 on windows and ran the setup input wizard (don’t think it should have done much because it’s a UART remote and there’s no calibration needed) it gave the message “Your VESC hws old firmware and needs to be updated. After that, the motor configuration has to be done again”. I didn’t update the firmware because of the weird FOC only custom thing, but it worked fine immediately after this point.
Now I have the two ESCs connected by CAN, making this horrible noise and never moving in forward, only slowly and after a few seconds of holding reverse
It’s showing lowish current <10A in the RT data and very low <1% duty cycle
Yeah I don’t think I’ve tried that high current with that low tooth count but sounds right. I might reword my original answer, 14 is more like bare bare minimum
There’s a little bit of a tradeoff; high Kv means you get lower motor pulley tooth count so you’re probably gonna skip a load. That’s unless you balance it with bigger wheel pulleys (but idk how much bigger you can go on 115mm wheels) or lower pack voltage. I use 140Kv motors because I also prefer torque and didn’t fully do my reading first, but it’s not the end of the world for me
It miiiight be passable with an idler but without, it’s just too small. I think my happy medium is 15T, I run that decently loose on my BN idler mounts and I’ve only had it skip if I didn’t have the idlers set appropriately
For a torque build, I’d maximize my wheel pulley, and then use 15T with 140kv
Technically 14T pulleys would wear out a lot faster too
But if your top speed is 30km/h can you really reach that point? Maybe I’m missing something but I can’t see how you’d manage to push 70A through a gearing like that in the first place, never mind sustaining it for long enough to hit a steady state above what it can handle
Well, is there any drawback to getting big motors right away? The battery can take it and pulleys can be changed rather easily later on, no?
you know - just in case I DO wanna go fast sometime in the future.
Also, I weigh almost twice as much as most skating companies consider as “normal”, so I really kinda DO need the power…
Yeah fair fair I was gonna say something similar. I’m a bit of a hypocrite because I’m using 140kv 6384s in a mostly flat city with 120mm wheels, I’ve no need for something that big either and bought for exactly the reason you’re saying. I’d rather be able to gear up for speed and have power in reserve, I’ll pay the efficiency hit. The only bit I’m regretting so far is that it’s physically heavy for portability and a hit harder to assemble unless you go for really big trucks and stuff
I’m fairly big as well (105kg) and it’s so funny feeling a board pull the feet out from under me
Okay, I have absolutely NO clue about pretty much anything you just said, sorry.
Everytime I think “right, I think I kinda got this” some dude like you comes along and shows me how little I actually know about all this
Thanks for helping me learn though, I really appreciate the help.
Yeah sorry that’s more a problem with my phrasing than you tbh
Basically, a motor has a limit to how fast it can spin at a given voltage. If you hit that speed, it can’t accelerate more, so the only way you can draw more current through it is by like going up a 100% incline and pulling heavy stuff. So my logic was that if your gearing is super low and you hit the top speed really early you’re rarely going to draw huge amounts of current and definitely not draw it so often that you’d overheat. I’m not 100% sure how correct that is though, I haven’t tested out a really high power low speed build so I was asking Shuttershock if he knew something I didn’t
Found it! I had the App Settings in the secondary CAN-connected ESC set to “UART and PPM” and when I switched that to off with just the main ESC set to UART it behaved itself
If it helps you decide on a motor option, here is a moderate pace ride from today on a 12s single 6374 190kv with 16/36 gearing and 85mm wheels, geared top speed of about 32mph/52kmh. Pretty good acceleration. VESC motor amps is set to 90A but the motor won’t seem to take more than about 88A so that’s probably it’s limit.
6374 190kv is a great performing motor, if I were to size up it would be a 6380 from Torqueboards if/when he gets it in stock.
I would avoid sealed motors, motors with a big end bearing, and low KV motors. 170kv min.
Quick boardnamics 6384 motor question: will this motor, 15mm wide belt/pulley setup, BN mounts with idle pulleys and BN270 hangers all play nice together?
yes, I’ve run this exact setup but with larger motors, works just fine. there’s not many esk8 motors that are too big for the gargantuan BN270 hangars.
if you get them pre-cut for gear drive the shaft will protrude 22mm from the can but if not it’ll stick out from your motor pulley a bit, it won’t change anything if you’re using belts besides the looks
