with 8s 800kv 11/72 150mm wheel. the good harden steel gears were a fairly rapid wear part. at 10/72 it was worse.
I switched to 8s 540kv so I run 14T pinions which have really lasted.
so if you’ve got lower kv, and taller wheels. you’re likely really pushing the pinions hard and should expect low runtime.
when people ran non hardened steel. pinions would vanish in a day.
exactly what I am seeing. The wheel spurs look like they didn’t even take much if any wear, and those are just 1/4" lasercut chromoly from sendcutsend, even the teeth is lasercut. And not hardened.
Yeah that’s what I figured. I’d ideally have wider spurs and maybe even mod2. I just hope my 2 sets of wheel spurs will survive until I am ready for inrunners financially.
I do hope quality hardened gears will get me some usable ride time though. If I have to change pinions once every two months I can totally live with that. As is though, weirdly I am not really seeing a difference in torque between different pinions. So maybe I should run more teeth… I don’t know. Really need to figure this anomaly out. But doing drag times before I am fully swapped over to G300s is not gonna happen now.
Reckon one side still works?
I was just thinking about encoders I’m trying to figure that out so I can get more amps without the overcurrent spike breaking stuff.
MakerX needs to make a D100P or something that uses the same mosfets etc (they’re pretty solid like 100v and 1.4 miliohms resistance iirc) just built out like a spintend with 2 separate pcbs for the voltage spikes and emf or whatever coming from the 400A phase, copper rails and all the mosfets on one side for better cooling when using an additional heatsink.
Don’t know if it still works as is, the previous one that blew up was way beyond repair for both sides.
This one looks way less bad, and the other end of the board looks fairly intact - maybe one side is salvageable with some work put in, but I don’t have the time to diagnose it deeper within the next couple of weeks. But even if I manage to salvage it, I wouldn’t want to put it back into this board.
They actually have a ton of gate charge, so I imagine switching losses are pretty high. But yeah for 1.5$ each the fets are great value for sure and also going towards more switching losses is probably a good thing for high power if the cost of the fets need to stay reasonable. Separating the powerstage and the logic stage sounds like a good move.
I think the #1 thing that it needs is good shoot through protection though. I think that’s what’s really happening on most of these that are the blowing up - it essentially shorts out the battery by messing up the switching for whatever reason. And then acts as a fuse.
You must be new to VESC 
I don’t know man if my buddy can build an ESC with shoot through protection why Vedder and MakerX can’t properly implement one with a way higher R&D budget
More powerful fets always seem to have a higher gate charge, does it make a noticeable amount of heat at high erpm or is it an issue to gate drivers and how VESCs have been blowing up quite a bit and in unique ways?
Also could the long motor wires with 200A be messing with sensor readings so shielding or mounting the VESCs at the end with long battery leads could help?
So Prague updates. This event didn’t go smooth for me.
It started by blowing up an ESC the day before starting to drive to Prague. At Prague, on the Thursday Kartplanet session I didn’t ride at all, I was just working on my board the whole time. Swapped in a D100S, huge shoutout to @TZDKB for bringing it as my replacement part, after getting to the point where the only thing left was to do vesc config, I went to turn it on and nothing happened. From the quick measurements we took with a basic multimeter next to track, seems like the internal buck converter is blown, which should be fixable. So, in goes the other D100S that Tilo happened to have with him - by the time I managed to fully install this, change pinions, and run vesc detection, it was Saturday 3am.
So Friday I was running my mountainboard JumpBro on this board’s battery and 9x3.5 knobbies on Kartplanet. My times were, as you’d imagine, pretty darn slow. But I at least had something to ride.
Fast forward to Saturday, I went on the track with the newly repaired raceboard on lubricated fresh gears and even some HFI configured, although on FW 5.3 as per MakerX’s recommendation for stability. The torque actually felt great, which I guess would be due to lubrication.
I did manage to at least take a cool video using the above mentioned camera mounting setup.
Before my fall, my qualification time was 1st and the lineup was crazy strong. Qualification here is just your best lap in freeride - so with more laps I am sure I could’ve gotten an even better time. After my crash though, I dropped to 4th starting position. I skipped the whole race though.
I managed to record a video about how the wobble took me out.
Helmet took a pretty big hit, people were telling me afterwards that the sound of the helmet hitting the ground was scary loud. Helmet got cracked internally. Board decided to go crazy after the fall, remote is definitely messed up, have to do more diagnosis though.
I was knocked out for maybe 5 seconds, then 5 more seconds I was conscious but wasn’t in control of myself, then after that I just had a mild to medium headache.
Went to the hospital and got a CT scan just to make sure, and all is well, no injuries just gotta take the next few days fairly chill.
ECE 22.06 is a must for esk8! And I can stand behind the Sedici Duale as a very protective helmet… I think in a lesser helmet this would’ve ended way worse.
I think the cause of the wobble was not retightening my fresh bushings a couple laps after installing them, as I’m running new bushings now. They have definitely softened up, that said it doesn’t feel like if all preload would be lost.
93/95 cone, 95/95 fatcone.
47.5/17.5 angles on 120cm / 48" wheelbase. Standing platform about 30mm below axle.
But the bushings especially in the front are definitely on the super soft end of the spectrum. Ideally I’d have run at least 95/95 but that’d have needed more duro in the back too, and 100 wfb fatcones don’t exist as of now. Definitely need more experimentation. The wobble for sure came from the front. All my prior wobbles on Dualities were slow and easily controllable - this one was crazy strong and violent. So not sure what’s going on here exactly. @Titoxd1000 maybe the 47.5 front angle is doing weird things? Or just the super soft front bushing setup?
Damn that shit whipped you down quick!
yeah serious whip. that was painful to see.
Glad you are okay man that looked like a nasty wipe out.
Don’t think it would be the high front angle… Bushings do look a little a bit soft. WFB seems to break in more than the other formulas and may need retightening after first ride. I tighten enough to get rid of most of the slop you can feel when moving the hanger by hand, maybe leaving a little to help initiate turns. Also check nut nylon still has resistance, I had one backing out before.
After more riding I think the front cone, even the more mild angle, doesn’t seem to be supportive enough so I’m going to test barrel/fatcone again. I think I will get a 98a wfb in fatcone or very similar style shape.
Yeah I noticed WFBs break in more. Conical shapes seem to break in even more also. The nut is on there tight.
Usually though when I didn’t retighten bushings after breaking them in, the wobble was super slow and very controllable. This time it was much, much more violent. I want to figure out which setup change did this.
I don’t think it’s weight - the 9x3.5s were about 1.5 kg per wheel whereas the kart wheels are 2550g including the gears if I remember it correctly, I weighted them a while back. Maybe that’s gears excluded idk. Went from maybe 7kg total front truck weight to 9kg. And from a very easy to control wobble to a super violent wobble. Doesn’t quite add up. It might have been a contributing factor, but definitely not the main thing.
Regarding tire height, there was also no difference between how wobbling felt on Supernovas vs the 9x3.5s so I don’t think that alone would be an explanation either, might be a small factor.
From my talks with Morgan, his V6 wobbles more violent than his V5 when a wobble does occur. So at the moment my primary suspect is the roughly 30mm below axle ride height - which is even more than the V6’s 24mm. I need to run a softer setup to get enough leverage, which in turn results in something that might be more prone to wobbles if my theory is correct. The lower leverage I had with this ride height, coupled with the lower leverage of having to run trucks at higher angles due to wheelbase and lack of flex, meant I had to run bushings that don’t do much at all, otherwise I was unable to make turns as tight as I want to.
I think I’ll go back to the starting setup -
then start again the frame from scratch. With two goals: axle exactly inline with deck (maybe @Titoxd1000 you were right all along), and the shortest wheelbase possible that gets rid of wheelbite. Then need to decide if fixing deck flex is a must or not at that point - because ideally I would have some deck flex in the chassis.
If that does feel good, that wheel position relative to the deck can go into CAD and a radium inspired swingarm setup can be designed to go between the deck and the shortest possible truck position. As a bonus, maybe the higher ride height means I can design a belly that can take all the ESCs and all the batteries? But if I have so much space under the board maybe I can also just leave that empty to be able to run smaller wheels if I ever want to 
Yikes! Glad to hear you’re recovering well.
Sounds plausible, since lateral G push results in steering forces and vice versa, a neutral deck height might be the thing that slows down the feedback loop by removing the coupling
I’ve recently started riding with a steering damper, and I really like it so far. If you like loose WFB, you might appreciate it too. It’s let me run a board really loose without the front end getting twitchy or diving into turns too much, and of course it stops wobbles from growing out of control.
Hard knocks dude…
Glad you are ok.
It’s so cool to see how into all this you are.
Really next level.
I wonder if the new Stooge boards have the same issue, I think their ride height is also below the axle. Unless I get something wrong.
I remember reading back in the days in the Silverfish days (longboard forum) that once you get really low on the deck height you lose “all” your leverage. That does sound like the leading culprit thinking about it more. While there are some benefits of going bellow axle, the potential trade off is if it wobbles kick in you have less leverage to correct them. A big benefit with in line axle height would probably be that it’s the most consistent and or linear feeling.
V6 is severely below axle, ~80% as deep as me.
The others are barely below axle. Maybe barely below wouldn’t feel too bad yet. But I want to stick to inline from this point.
When you have your foot platform above the axle (or roll axis), I always call that topmount leverage.
Topmount leverage give you control authority, and there’s some argument that it allows for better grip because you’re able to run harder bushings and load up your inside wheels harder.
When your foot platform drops below the roll axis, I call that Hammocking.
You almost always want to avoid hammocking at speed because Lateral Gs from making a turn are applied below the roll axis, which actually puts more energy into to leaning the deck.
You get this weird situation where you have more stable resting position, its self correcting, and gives turning a low sweeping feel. Unless you’re going fast, then it starts liking to dwell in turns, or can even lock the board into a turn in a worst case scenario. That might potentially make wobbles worse if the the energy it takes to pull a board out of a turn is greater than your boards strength at holding center.
If lateral Gs with foot platform below the roll axis contributes to lean, then lateral Gs with the foot platform above the roll axis actually help push the board back to center. So even though at low speed the height can make the deck feel divey, it can actually contribute to stability at speed in its own way.
My favorite setup lately is having a neutral ride height for the rear foot, maybe 2-3mm above the roll axis, and then maybe 3/4" of topmount leverage on the front foot, which is a decently healthy amount. So I can focus on using my front foot to control the board, and let my rear foot be more passive. And the higher front really encourages you to keep that front end weighted, which also helps keep the board in control. But, I’m doing completely different things for my riding, not going to say that’s a race viable approach or anything like that.
The only other thing I can think of worth mentioning is that, the roll axis and axle height are only the same thing on a rakeless truck, like 3 the Link. I always forget how to precisely figure what the roll axis is, but on a channel truck the middle of the kingpin is a good approximation, which is slightly higher.
So if your ride height is below the axles, you’re definitely a decent ways below the roll axis, and well into dealing with some of the weirdness of hammocking.
If you want neutral, you’re actually going to be slightly above the axle.
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