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Everything posted by Scatcat

  1. My Mten3 Broke and What I'm Doing About it

    Imagine a situation where the GW people would be in the forums listening, telling people they won't void their warranty for using the obvious remedy... Just showing they see and listen, that they're on it.
  2. My Mten3 Broke and What I'm Doing About it

    If Gotway had been a US, EU, South Korean, Taiwanese or Japanese company, that there would mean a full recall/free replacement scheme costing a small fortune...
  3. My Mten3 Broke and What I'm Doing About it

    Correct me if I'm wrong, but doesn't it seem that the biggest problem overall for GW are power spikes? It is as if the combination of hardware and firmware doesn't include any provision for limiting power runaway conditions... There should be some damper built in to protect MOSFETs, capacitors, wires, batteries and so on. The obvious place to put such a provision would be in the firmware, making sure sudden inputs don't burn out the circuits. It's a simple thing to do, but of course like with Clausewitz comments about simplicity in war even simple things are quite complicated. You need to create a selective lag, that will stop sudden spikes, without creating hesitation in the firmware. Compensating for not allowing the power-rise to go beyond a certain limit within a certain time-span, with applying the power actually allowed for a few fractions of a second more. For example, if the combination of starting uphill at slow speed and a sudden bump in hard mode creates a "requested" spike of 100A for a twentieth of a second, that is probably not what is really needed, and something will probably burn if that power is allowed. It would be better to provide 40A for three tenths of a second to achieve the same stabilising effect without burning anything. Or am I wrong here? If the firmware has functions to limit spikes, adding a fuse is actually only for those WTF anomalies where the built in limits can't do anything. Where the alternatives are a face plant with fried circuits OR a face plant without fried circuits. Having used both GT16V1 and GT16V2, I think I can safely say that V1 had the same problem I described above. There was nothing limiting anything, and there were reports of fried boards. V2 on the other hand won't let you do the stupid unless you're set on being terminally stupid...
  4. My Mten3 Broke and What I'm Doing About it

    Actually it may be slightly higher than 35A. I got a spike with a tilt-back today going slightly uphill in a headwind at about 22-25mph. Checking the log in wheellog I read the spike at about 35A, but it might have been 36 or even 37A, as I read it while riding. It is pretty consistent with other overpower tilt-backs I've had, it tilts around that number, keeping a few amps in reserve for when you really need it. It is also pretty consistent with an 80% power tilt-back, if you presume the max continuous amperage is 10-11A per pack for the Sanyo's.
  5. My Mten3 Broke and What I'm Doing About it

    Well, my GT16 will happily tilt-back if I hit about 35A at 80% charge. As long as you have security settings in the wheel that won't let you get that type of spikes, you're good. The fuse will burn if something is seriously wrong, and not necessarily because you go fast. The worst spikes in my limited experience come at pretty low speeds when you push hard.
  6. My Mten3 Broke and What I'm Doing About it

    Because the mentality it "get it ready, get it out the door, sell, sell, sell". In itself that is not a bad thing, but as soon as you start taking short cuts to achieve it, you're in for trouble.
  7. My Mten3 Broke and What I'm Doing About it

    I'm utterly fascinated by Gotway as a company. How they combine brilliance with pure distilled fecal matter... Like in this case. On their hands they have a stunningly brilliant concept, refined to 10" of pure joy. Everybody who's tried it like to recite poetry about its magnificence. Then it turns out some high school level moron that can't count to eleven with shoes on have decided to join the battery packs with the equivalent of candy tin foil... It makes you wonder if they actually WANT to survive long term as a company? Gotway can't afford many more flaps like this. Already there are quite a few sellers that won't carry their wheels because all the reclamations and service requirements eats into the margins violently. GOTWAY, it is so simple: When you design a new wheel, let a certified experienced electric engineer go through the design and make sure it can safely take the strain we put on it. It will cost you a few thousand dollars, which you will reclaim within the first months in spare parts you don't have to send out, and returns you will avoid. Your sales will also go up, slowly at first as people won't really believe you've cleaned up your act, but faster and faster as people realise they can now safely get the fastest and most exhilarating products without expecting failure. I respect @Marty Backe for his love of Gotway wheels, and I sure as hell would like to have a working MTen3, Tesla or Monster, for the fun and brilliance of the concepts. But WTF, what is this? Amateur night? Aren't these people supposed to be engineers?

    Or... all of the above...

    Damn! Those side slips are wonderful! If the weather gets just right and I can find somewhere to train, I would like to learn to handle such conditions! Looks like a ton of fun!

    No, I haven't, and no, from the kind of experience I've gotten with the GT16 I don't think so. I don't think another wheel would make that much of a difference for better stability, maybe even the opposite. The dual wheel is actually MORE twitchy on anything but a smooth flat surface. And the best meter I feel you get for what you have under your wheel on a one-wheeler is how the yaw stability is affected. If you feel the wheel would like to spin turn on you easier than normally, you can be quite sure you're on a slippery surface and adapt your behaviour to that fact. The thing I do when I realise I'm on ice, is letting the speed fall naturally and keep the turns in an mostly upright position with only the wheel leaning and the speed low enough to avoid powerful sideways forces. If you haven't "commited" your body-weight in any direction, it is not that hard to compensate for small slippages. You have to go rather slow though I actually find it almost easier to negotiate the ice on my wheel than on my feet. I say almost, because the center of gravity is higher, but on the other hand your balance is more focused and to some extent easier to predict. I think I would prefer my feet, but I was very surprised when I stepped off on ice the first time and almost slipped. On the wheel it hadn't really felt that bad.

    Not on the center thread. As long as you go straight forward there is not much use anyway, except for braking. And if you put them on the first thread to the side and they stick out 2mm, you should get enough traction even going straight, but without the whole weight on the studs. Also lowering the pressure to ~2.7 or so should do wonders for extra grip on slippery surfaces and lessen the tendency to follow any cracks and ruts in the ice. Fascinatingly enough the grip on ice even without studs are not really bad. I wouldn't want to do any panic braking, but it's far less precarious than I thought it would be. I actually feel less stressed on ice than I do in rain-wet loose mud - or the worst: wet moss and mud combined. Adding some moss to the mud makes sure there is no friction at all when you side-slip... I do suspect however, that the wet snow/ice goo outside today is almost as bad as moss and mud...

    I'm considering these http://www.best-grip.com/site/en/prodotti/tutti-i-prodotti/ The 1000 variant should do the trick, goes in 6mm and sticks out 2mm. The worry is how much damage they do to the tyre... It should be possible to just unscrew them and continue using the tyre, but maybe I should get an extra just because...

    What I actually hope for is some warmer drier days to melt and dry the slop up, and then a fast conversion to cold dry weather - snow optional.

    Exactly! In the bloody afternoon half of it melted away, and the other half was gooey, slippery slop with pieces of ice here and there to ambush you when you least expect it.

    Santa Claus

    Today I gave up, at least temporarily. Waking up and looking out, you could barely see 50m because of snow in the air. This is when I was going to work, biting the bullet and taking the tram. It's OK, but takes twice as long.
  17. The Photo Thread

    Nah, if I go any direction that I don't want it will be sideways or my fat arse It turns out I have better grip and road handling than the mountain bikes sharing my lanes... The only really scary situation is ruts in ice, that try to steer you wheel for you. And I take the tram for the last bit, since the city seems to have run out of sand before treating that part...
  18. The Photo Thread

    Can't you send 14 of those 34 degrees here please? And some sun too if you please?
  19. The Photo Thread

    Right now it's 24°F here, and the roads are mixed ice and sand. Let me put it this way: there will be no speed records achieved this week...
  20. Video: Gotway Monster 100v version

    $3.4K........ AAAAARGHHHH! M.U.S.T R.E.S.I.S.T
  21. My Mten3 Broke and What I'm Doing About it

    If you get nominal voltage out of the pack and normal endurance, the cells are probably good. I know I am one of those that frequently tell fellow vapers and other ppl handling lithium batteries to show them respect, since they contain the same amount of energy as several grams of TNT. But in reality they are not that fragile. Unless you have punctures, serious dents or the battery has vented, the battery is probably good. The damage that could affect such a cell, would be overdraw of power, where just that cell got temporarily shorted. But looking at the damage that seems unlikely. Even if that happened, and unless you had a vent, the damage done is not catastrophic, but will rather just lead to fewer cycles and less capacity. And people, how many parallels there are in the design may or may not mean it's enough for safety. It depends a lot on which cells are chosen for the packs. Some cells can take a continuous power for the whole cycle, but will get damage after a rather short spike of twice that power. While others take almost no damage at all, even with loads that are four times the nominal, as long as the spikes remain short. Consider the Sony VTC5A. They have a CDA of 25A, but can take 40A for five to ten seconds without failing or getting damaged. They will temporarily drop something like a Volt while pulling such amps, but they can do it. Suppose someone put VTC5As in a 20s2p, that would mean the pack could give you ~5kW or so for a few seconds. I doubt any EUC mfg's will ever put VTC5As in their packs, if for no other reason that the things are pretty expensive. But even the cells they use can take a lot more than we think.
  22. So I bought a second hand GT16 for about 900€, it had 74 km on the clock and no real dents or scrapes. Given a new one in EU would cost close to twice that amount I took a chance, knowing full well that my frugal side could come bite me in the rear if I were unlucky. I got it on eBay from a seller with 60-ish positive comments and no negatives. I got it pretty fast, about a week from payment to delivery, and unpacked it with some trepidation and a suspicious mind. The positives were: It had no real dents and scratches except for on the pedals. It started OK, and balanced perfectly The app connected without fail, and the meter matched the pictures on eBay. It came with a trolley. The negatives on the other hand: The trolley was partly broken, but fixable. The LEDs on the sides were not connected, and there is not even a cord to connect them to unless that is stuck in the controller compartment. The mudflap is just as useless as people say, I'll have to look into what can be done about that. One of the plastic dampers for the pedals were missing, I fixed it with a skateboard riser. The same pedal were loose, meaning would not stay up when risen agains the shell. The shell sat somewhat loose on the wheel, it seems the screws connecting the shell to the wheel were not tight enough. Some of that is the breaks of the game when you buy second hand, but a few points were a bit worrying. Standing with my weight on one of the pedals the first time made the tire "screech" against the shell. The dreaded "cracked axle" ghost raised its head grinning my way. But as it turned out, the reason were fourfold: One - the air valve stuck out a bit too much, two - the screws to the shell needed tightening, three - the shell is not as rigid as it should be, and four - the tolerances are too small. The last aspect is my main negative feeling about the wheel, it could well have a quarter-inch more space around the tire on all sides, where the tire meets the shell. That would make the mudflap immensely more useful, would eliminate the risk of the valve or the sides of the tire rubbing against the shell, and maybe even allow a 2.5" tire upgrade... Also, the screws connecting the shell to the pedals, which AFAIK are the only twelve screws that hold the shell to the wheel, doesn't even have washers. Basically the screw sits directly on the shell, which seem outright stupid. A metal backing, washer or a plate, would spread the forces over a bigger area, making the connection stronger. Four of those are the bottom screws that sits below the pedals, and there is no form of metal backing there either. Sure the forces push the pedal towards the shell, but there are side-forces too. I fixed the trolley with loctite, a cable tie and some really strong weave-tape. I also added chrome strips, to avoid my clumsy self killing the beauty of the wheel. The loose pedal turned out to be a combination of the tightening screw being loose enough that the pedal axle had moved around. So when the previous owner tightened it, the flat part where the adjustment screw should grip had slipped around. Taking it apart, and putting it together correctly solved the problem beautifully. I added skateboard gripping tape to the pedals, the really rough kind. You can't see it on the pic, but there is some silver tape on the shell under the pedal to avoid imprinting the grip tape on the shell. Will get rubber stickers or something to replace it with. Now to learn to actually ride the darn thing... I now realise my Inmotion V3 have given me some really, really bad habits. The first half hour, in the middle of the night, were like going to the bloody gym! Today, the second day, I actually got on unassisted for the first time and rode my first ten meters before a controlled stop. Good exchange for 45min of trials, still exhausting though. There's still a lot of familiarisation to do, and a lot of twin wheel stupidities to unlearn, but I see the light at the end of the tunnel. With this tempo I will be zipping around in no time The bad habits to unlearn are: almost no leaning of the wheel before getting on; getting on first, then start rolling; going really, really slow – plus the lower center of gravity on that wheel with lower pedals and 14" wheels. I look forward to getting used to a "true" unicycle. I'll report more as things progress...
  23. The Photo Thread

    Damn this f-ing climate to hell! And tonight this shit will freeze...
  24. If you have android I recommend Wheelog, it is sooo much better than the Rockwheel app. The only thing I use the Rw-app for are modes.
  25. Default angulation? I'm not sure I follow? Did it reset by just disconnecting and connecting the battery?