meepmeepmayer

Gotway: "LOL we put glue on our mosfets!" Kingsong: "LOL see you in 2020!"

I was going to say I was too harsh on this, and for like $500 it might be a nice fun (and sweet looking) wheel. But the regular price is $900!?

Du bist ganz einfach zu langsam. Stell dir vor, du wärst mit dem Fahrrad unterwegs. Was wäre bei der gleichen Geschwindigkeit? Entspannt fahren oder eher rumwackeln? Bin mir ziemlich sicher dass das das Problem ist

Wichtig: nicht zu langsam fahren! Genau wie beim Fahrrad. Schnell ist einfach, langsam ist schwer. Also aufs wheel stellen (ggf. mit Hilfe von einer Wand oder einem Pfosten) und dann direkt auf 15-20km/h beschleunigen. Je schneller, desto stabiler. Du musst es nicht übertreiben, aber wenn du beim Fahren merkst, dass du instabil wirst, dann beschleunigen, nicht bremsen! Ist erstmal vielleicht unintuitiv, aber so gehts am Anfang. Mit der Zeit kannst du dann von selbst immer langsamer sicher fahren. Viele neue Leute machen den Fehler und krebsen im Schritttempo rum. Das ist natürlich viel schwerer. Langsam fahren, Kurven, Aufsteigen ohne Hilfe kommt später. Erstmal lernen, auf dem wheel zu bleiben. Dabei hilft Geschwindigkeit. Wenn du 30m kommst aber nicht weiter, bist du höchstwahrscheinlich einfach viel zu langsam. Gibt sonst keinen Grund, wieso nach 30m Schluss sein sollte

Well, it's the weekend, but still...

I sent him a quick warning yesterday. Not sure if he got it, I didn't get the usual auto-reply email.

To be more clear: DO NOT BUY A NIKOLA FOR NOW! IF YOU HAVE ONE, YOUR BOARD MAY BE A TICKING TIME BOMB! IT MAY NEED REPLACEMENT OR A REPAIR THAT REMOVES THE GLUE BETWEEN THE MOSFETS AND HEATSINK. You can buy Nikolas again when they come with good boards. I assume they will do that from now on. But beware of older stock, e.g. on Ali. Maybe go for a trusted seller like ewheels as long as it is questionable which stock (good board or bad board) you'll get. The sticker on the board contains a date (e.g. 190601... means 1st June 2019). If it is before now, your board may be affected by the bad assembly method. If it is after now (maybe give it a grace period), Gotway will have fixed the wrong assembly method and the board should be good. (*should* I hope the sticker date is the board+heatsink assembly date, not the production date from some supplier.) We don't know if every Nikola board is affected because all Nikola boards were assembled by the bad worker(s), or if some are good and some are not depending on the worker. Everyone who checked so far has reported a bad board!

I love how you guys matter-of-factly reply to a sarcastic post - with good info

Range is pure lies, too. It highly depends on the speed and rider. A nice rule of thumb is 1000Wh = 50km/30mi (for an ~80kg/180lbs rider at 30-35kph/19-22mph) which is 20Wh/km (33Wh/mi), and other battery capacities are proportional to that. Compare that to what the manufacturers advertise (60kg rider at 15kph is their excuse). Speed is reliable info. Just don't confuse an absolute top speed at 100% battery with a normal riding speed over the course of a ride. E.g. Kingsong wheels with 50kph speed limit (like the 16X will presumably have) are not good if you actually wanted to ride 50kph. Because you'll constantly hit the alarm/tiltback then. Or a V8 (30kph top) is closer to a 25kph wheel in practice, because the top speed reduces with the battery charge. So remove 10%-20% from the top speed for a realistic speed that you'll actually safely ride with a given wheel. By the way, ewheels charts are full of errors, don't put too much importance into some single number when comparing. Just ask here Real life experience is all that matters for EUCs anyways. (You didn't mention it, but incline numbers are the most meaningless of them all. Ignore them completely.) Here's an example of battery math (for the 16X). The size of the 16X battery is 20 * 3.7V * 6 * 3500mAh = 74V * 21Ah = 1554Wh [= "1600Wh"] [1 Ampere * 1 Volt = 1 Watt] The battery pack is made of 6 blocks of 20 cells, the nominal ("average" from full to empty) voltage of a cell is 3.7V, and each cell has a capacity of 3500mAh. That gives a nominal voltage of the battery pack of 74V and a capacity of 21Ah. Multiply it to get the 1554Wh number for the battery size. Arguments about this number are because people use different numbers. Is the nominal voltage of a cell 3.6V or 3.7V? Is the cell capacity 3500mAh or 3450mAh? (In the 16X case, it's 3500mAh cells, on Gotways, it is not.) Should we call this a 74V wheel (by nominal voltage of the battery) or a 84V wheel (by maximal voltage of the battery, which is 4.2V per cell, and 20*4.2V is 84V)? Is "1600Wh" lying or just some rounding for ease of use? Etc. Doesn't really matter as long as everyone knows what is meant. In the end, there's only 3 relevant voltages (with the exception of the Ninebot One Z): 67.2V (16*4.2V) which seems to be a thing of the past, 84V (20*4.2V), 100V (24*4.2V=100.8V). So there are no small differences there. It's one of those three. Voltage isn't really good for comparing wheels anyways. It says very little on its own. Battery packs also come in only a few different sizes (x blocks of y cells, where y defines the voltage of the wheel). Like 1600Wh (6*20), 1020Wh (4*20), etc.

If you do it in real life, it is realistic. Fully agree with the rest. Wheels must survive 99.99% percentile extreme cases, not the average rider or what some low-weight Chinese falsely believe that is.

If it is really glue (looks like it), I wouldn't buy a Nikola now, at least from Ali or any other source without excellent service. Because then all boards might be affected and it is no isolated incident, just the first. With the uncertainty if they will use a better board in future 84V Nikolas I wouldn't buy a Nikola now, too. 2 good reasons to wait. Frustrating, but the reasonable thing to do. I'm certainly waiting until more info comes up. Though I certainly appreciate any involuntary beta testers ordering the 2100Wh one and giving us a look (if only at the crash and subsequent service odyssey).

Unless I'm very mistaken, the Monster has always had vertical batteries. Maybe you're confusing it with the ACM and msupers which have horizontal batteries? Here's a picture posted by Jason in 2017 in your very own first Monster thread: Looks vertical to me For comparison, the new Monster shell from page 2 of this thread: But I have to correct myself, there doesn't seem to be space for longer batteries in the new shell. I was hoping one space could now hold a 24s3p 100V battery each, that would have allowed a 2800Wh 100V Monster. But doesn't look like there's more space.

I think they just left more space so the shell can hold more battery configurations.

The only thing that can go wrong is different/non-matching connectors on the battery pack and board wiring. For now: 2 types of battery packs - 650Wh (20s3p 2900mAh) and 800Wh (20s3p 3450mAh) - are the only two packs used for all variants of: 84V Nikola (excluding the rumored 2100Wh version), 84V MSX, 84V Monster, and older wheels like the msuper V3, ACM, ACM2. One type of battery pack - 615Wh (24s2p 3450mAh) - is the only pack used on all variants of: 100V MSX, 100V Monster, 100V Nikola (presumably, nobody's seen the 1845Wh yet). All battery sizes of those wheels are just different numbers of one type of these packs. So it is extremely likely that the packs are interchangeable.

The Nikola's smooth rounded shape seems ideal for using motorcycle tank protectors. Those are stick-on, profiled rubber mats specifically designed so the motorcyclist's legs can grab the otherwise slippery sides of the motorcycle body. Which is exactly what we need for EUCs (padding isn't important, as usually your legs don't even touch the wheel unless you grab it on purpose). Only downside: this stuff is expensive as ****. Google "techspec". But cutting one mat for ~50 should be enough for one EUC.

"84.2V" is simply an error. Should be "84V". Nothing more to it.

Marty you're a hero! Great experiment! And that theory of yours is depressingly realistic. I feel sorry for Jason. He's busy enough and then crap like this (presumably) happens. Again. Fighting for the manufacturer to even acknowledge that there might be an issue, let alone any remedy efforts, etc... At least he has you, you're probably helping him a lot.

@bruno356 You may know more than I do, but shouldn't it be irrelevant how many cells are in series (the wheel voltage)? They'll all get the same current if the number of parallel blocks is the same, right? So 10A/6blocks = 1.67A per block and then every cell in that block gets that current which is below 0.5C.

I'll wait til you can say more, Marty Hopefully, even if this is glue, this was just a singular accident and not some moronic assembly guy using glue for the mosfets. (Trying to stay sane by assuming the best)

10A/6 = 1.67A is still below the standard rate. I don't think charging even with a 10A charger would affect battery life. And cell balancing doesn't depend on the charger used. The battery just needs to be full for the BMS to balance, that is all.

WTF?

I think that is for Gotway/GX connectors. I seem to remember an 8A number from KS, but 10A souns fine then.

Careful! The limit might not be the cells, but the charge port. I can't find the max amperage for that, but it's probably the limiting factor. Ask KS or ewheels or someone who knows before you melt your port.