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Showing most liked content on 05/28/2019 in all areas

  1. 9 likes
    I'm not sure how well people understand how the physics of a self-balancing wheel works, nor how fast things will happen (and therefore fail) at the RPMs, velocities, inertias, and rotational moments we're dealing with. If a rider leans forward and a wheel simply continues to rotate at the same speed it was already at, the rider will fall off the front of the wheel. The balancing mechanics require the wheel to accelerate to stay "under" the rider. If the rider leans hard (moves CG significantly forward), the wheel must accelerate aggressively to remain under the rider. Period. There's no choice to "just do what you can" or "just don't accelerate any more when at the limit." It must accelerate, or try to, or the rider will simply fall. The motor has a torque "margin," and that margin decreases with rotational speed. The faster the wheel is going, the less margin there is. In addition, the battery pack's BMS has a low-voltage cut-off that will simply stop the current flow if the pack goes beyond the lower safe voltage limit. The wheel's mainboard has no control over the low-voltage cut-off and will lose power along with the rest of the wheel when the cut-off happens. If the torque limit is exceeded, the rider goes down because the wheel is still trying but the motor just can't accelerate fast enough. If the voltage cut-off happens due to excessive amperage demand when the battery pack is depleted, the wheel will simply go instantly dead, with the same result. The result is the same, although high-speed footage would probably show a difference in how fast the wheel chassis/pedals rotate away from level and dump the rider when comparing between exceeding motor capability and hitting BMS cut-off voltage. No wheel can "just slow down" or "just refuse to accelerate further." It's just not possible. What it can do is to monitor all the known parameters (voltage, amperage, speed), provide audible warnings (beeping or voice), and as a last resort use tilt-back as a "discouragement." If pedal angle tilts back 10 degrees while trying to accelerate, acceleration becomes hard to achieve, although a determined rider who is standing with feet sufficiently forward on the pedals can indeed keep the wheel going at that speed, or even make it accelerate further...until the moment of failure. Not only can tilt-back be defeated on some wheels by turning it off, but it's also conceivable to lean into an acceleration so hard that there's no time to do the tilt-back before failure occurs. So, when going fast, don't change speeds aggressively via hard leaning, and when the battery pack is very depleted, the same is true even at much lower speeds.
  2. 5 likes
    yes that sounds about right. 95 Amps demanded, 90 Amps available, the missing 5 Amps get borrowed from you face as it slides down the road.
  3. 5 likes
    I ride in the hills a lot, and I accelerate while going up hills from 18mph to 25mph, sometimes with bumps. I have owned all the modern wheels. The MSX-84v feels the most robust doing this. No hint of any fatigue. I do it on my Monster 100v more cautiously because it doesn't feel as torquey and allows too much lean. I do this ride on my KS18XL as well with no problems. Even my MCM5 hands the hills like a champ, just a little slower, but still with incredible control. I tried to bring my Ninebot Z10 on this ride and it felt terrible. Felt very out of control and on the edge of dumping me going up, coming down and maintaining high speed (24mph-100%battery-riding tiltback) on rough streets. I took that Z10 everywhere to test it because I really loved the way it looked and just couldn't believe how terrible it felt, nothing to do with the tire as everyone talks about. The MSX, Monster100v, MCM5 and KS18XL have excellent track records of keeping the rider safe with aggressive riding, foolish riding aside. The Z10 has a terrible track record with aggressive handling with many riders falling on video and many people trying to explain away an under-performing wheel as rider error. I think the problem is expectation. If you buy a Z10 and think you can ride it like an MSX or KS18XL, you'll fall. If you ride the Z10 with caution and care, you'll be in for a unique riding experience that's not aggressive, but still quite fun. Ultimately I sold my Z10 because it never felt safe for my style of riding, even at low speed. This video is just another example of how easy it is to overpower a Z10.
  4. 5 likes
    This has already been discussed a lot on Facebook. I thought the consensus is that it's a simple overlean situation. When I view the video, I see someone that is going fast and then leans into it for acceleration. I recommend that people who like to aggressively lean forward for fast acceleration only do so when the wheel is basically stopped. At least then they won't fall to hard. If the wheel is already moving fast and you lean into it, you are creating extreme loads on the wheel and if the the system (motor power and available battery energy) is already near maximum capacity, the wheel will cutout. I have always advocated a Pebble watch so that you can learn the power consumption that your wheel requires. I can tell you that when you lean into an acceleration, there is a huge spike in power consumption. I will never lean into the wheel once I'm at speed. Unless I'm close to walking speed, my accelerations and decelerations are slow. It's amazing the lack of knowledge that I continue to see out there on how our wheels work and their limitations.
  5. 4 likes
    The rider commented on the YT video saying "92% of battery and speed about 40-42kmh" FWIW.
  6. 4 likes
    The engineering is our brain, know the limits keep to them or risk failure if pushed beyond 👍 Everyone should know the limits of there wheel they all differ and in different situations 😊
  7. 4 likes
    A license isn't going to change the fact that people will drive how they want. I'll enjoy my dangerous freedom over peaceful slavery thank you. TPTSB don't need any more of my time, money, or personal information.
  8. 3 likes
    If the charge is high enough. At 100% it degrades much more than on 40%. And temperature is an important factor. Temperature 40% charge 100% charge Table 3: Estimated recoverable capacity when storing Li-ion for one year at various temperatures. Elevated temperature hastens permanent capacity loss. Not all Li-ion systems behave the same. 0°C 98% (after 1 year) 94% (after 1 year) 25°C 96% (after 1 year) 80% (after 1 year) 40°C 85% (after 1 year) 65% (after 1 year) 60°C 75% (after 1 year) 60% (after 3 months) from https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries Where here full charge/discharge cycles count. So 50% to 0% count only half... Exactly. No. But this depends mostly how one defines fast charging. For most Li Ion cells some 0.4-0.5C are recommended. With the stock chargers one reaches about 0.1C, with the 5A chargers one stays still (with most of the big battery packs) well below the 0.4C. I have not found any study that there will be any notable difference. Just once one charges above 1C degradation is noticable. This "fast charging puts more strain/wear on the battery" comes from the RC groups, where LiPos are charged at really really high C rates (something >5C?). How to get this C Rate: One needs to know the capcity of the wheels single cells. They are mainly ~3000mAh(3Ah) or ~3500mAh(3,5Ah). And the second number one needs is the cells in parallel. Then one multiplies this number - the cells in parallel with the individial capacity. For an KS18XL (and high capacity MSX?) that's 6 cells in parallel with about 3,5Ah makes 21Ah. The "C Rate" is the charging current divided by this 21Ah . With some 2A charger it is 2/21 ~ 0.1C, with 5A 5/21=0.24C. A bit more on fast and ultra fast chargers: https://batteryuniversity.com/learn/article/ultra_fast_chargers As seen there, the high burdens while discharging (riding) the wheel is what could make one concerned... Not if one charges at 0.1C-0.4C. I'd assume even (almost) up to 1C should be neglectable compared to the discharge burden effects... Then you had it at ~100% just before the first ride. After the first day its well below (~60%?) and after the second day at around 30%?! Sounds like a great usage pattern. Just the time the wheel sits around high charges counts! Whereas in this example the wheel sits more time at this ~80% charge. Which should have much less effect than sitting half to one third the time at ~100% - at least there are no real numbers of this at batteryuniversity. They just mention on one page that charging to ~3,9V per cell there is about minimal stress. And this is about 74%. The downside on this pattern is, that its much more uncomfortable, takes much fun from riding and i could not really say if it's better or worse than the first... Yes - 60%-80% count only 20%/100% = 1/5 charge cycles. Quicker charging in the morning is better. There is no trickle charge overnight - li ion chargers cut off, once the finished the C(onstant)V(oltage) phase. But this CV phase is when cell balancing occurs - so this should be done from time to time to keep the cells matched! BTW: Quicker chargers have a CV phase that takes as long as the normal stock low amperage chargers. Its just the first phase with C(onstant)C(urrent) that is faster according to the current factor! The CC phase charges to about 85% and takes about 1 / "C Rate" hours for charging from 0% to 100% this ~85%(1) https://batteryuniversity.com/learn/article/charging_lithium_ion_batteries (1) Unfortionately at least here has to be mentioned that the charge % from the wheel does not correspond to the charge state of the cells. Wheels show 100% for cell voltages above about 4,1V and 0% for cell voltages below 3,3V (3,0V for KS18XL). Wheras a full charge cycle for a li ion cell is from 100% with 4.2V downto 0% at 2.5V (2.75V for some cells).
  9. 3 likes
    I've said it before and I'll say it again, I much prefer tiltback to tiltforth.
  10. 3 likes
    All this talk and demonstrations choreographing the anatomy of a proper fall is quite entertaining. I think @Darrell Wesh pointed out something that in my opinion has not been stressed enough; no one plans a fall. I have unhinged from my wheels as much as anyone in the game; probably more times than most. This includes being hit by car last week. In every incident I was praying; not planning. In the cases where I overpowered and cutout what saved me from more serious injury was my equipment. The only thing that I have remotely been able to plan is bailing; even that is not really a plan, but more of an emergency decision or reaction. Real life ain't no martial arts flick where the protagonist always has the perfect response to every call. Wear equipment. At minimum protect your joints: knees, elbows, wrists. If you are gonna be in high-speed, risky situations: your spine, hips, rib cage, and coconut.
  11. 3 likes
    According to Douglas Adams (rip) the best way to fall is actually to fly! Its a lot like falling, but you simply have to miss the ground.... "The Guide states, the main thing that flying requires is the ability to throw yourself at the ground and miss. It says to throw yourself forward with all your weight and "the willingness not to mind that it's going to hurt", however it will surely hurt if you fail to miss the ground. The difficulty is in missing the ground, and doing so accidentally, as "deliberately intending to miss the ground" does not work. "
  12. 3 likes
    exactly.. pretty much dont be foolish, mind your speed and monitor your battery.. in close to 20,000 km ive yet to have an accident on an euc because i never push the limits of what i know they are easily capable of
  13. 3 likes
    Actually not. One has to differentiate two situations here. First, what you already mentioned in your post before, accelerations from standstill or just high burdens at low speeds. Here the current through the motor could get way too high (would destroy the wheel), so the firmware limits the max current and by this the torque. The second ("normal", like shown in this video here) case is just hitting the max torque over speed limit of the motor. Here no limiting or cutting off is happening - its just the motor not beeing able to deliver more torque, because no higher current can flow (its limited by (battery voltage - motor back emv(generated voltage))/internal resistances). As nicely seen in As said, that's only true at standstill and low speeds and the current limiting is afaik realized as "soft" limit, by changing the pwm duty cycle.
  14. 3 likes
    It's not only possible but it happens I overleaned KS-16C on my fourth day of EUC riding and this was a humility lesson I learned for the rest of my EUC rider career And the situation was almost identical to what we seen on the video. I was trying to accelerate at speed, trying to chase skater on speed roller skates. Second time I overleaned KS-18L when trying to accelerate agressively from standstil. This time it was intentional and I was prepared. I did it just to confirm that you can overlean every wheel under some conditions. One of such demanding conditions is very hard acceleration from complete stop on a uphill slope. In general - it's quite easy to overlean wheel when conditions require more power than wheel remaining reserve. Wheel power reserve decreases with speed, so riding with speeds near to maximum is conducive to overlean. But it's also possible to overlean the wheel on start, when there is highest inertia to overcome. You just need curb, hole or something similar tha will cause another, momentary power spike that adds to already high wheel engine load and you have a recipe for a tasty faceplant
  15. 3 likes
    Looking at the video in slowmotion it's something about 2 seconds of very sporty acceleration _from_ some reasonable speed. That should be enough to overlean every wheel... This accident was for sure no cut-off. Once the BMS cuts off, the mainboard would have no power supply anymore and so no lights could be on anymore. In the beginning wheels had overcurrent (total output current) protection, which was triggered from time to time while riding. But this was not reported/seen/experienced anymore for some long time. Either they set the limit high enough and/or with enough time delay. Or turned it off completely like GW did (at least with some of their last generation wheels - don't know if they still have no overcurrent/short circuit protection in their BMSs) Voltage sag just by high current is very unlikely - the wheels have all kind of beeping/tiltback/speed limiting once one comes in the low voltage area around 3.3V (or does the Z10 stop at 3.0V as the KS18XL?). A sound lower cell voltage limit would be around 2.5 V (as specified by the manufacturer), but imho for critical task should be set somewhere as low as ~2V to not accidently cut off while riding in high burden situations. So there should be always around almost 1V for sudden voltage sags. One single cell with around 50mOhm would need to deliver 20A for this 1V voltage sag - so the 6 cells in parallel of the Z10 would need to deliver ~100A. Such burdens are not sanely possible with a wheel already at low to zero battery charge... And again such protective cut-offs would have time delays again. But not really much is known about the BMS details, especially the Z10s. Imho still everything here looks like an absolut normal overlean. At higher speeds one gets no "real" high currents anymore - the motor already generates enough back emv so there is not enough voltage difference between motor and battery so that any huge current could flow for some limiting taking place. And this not so high current is exactly the reason for the not so high torque available anymore -> normal overlean. The only battery related reason here could be that his battery maybe was not "full and fresh" anymore - so the torque limits are lower and easier reached. It's nicely seen in slowmotion that he got some "lean back" while riding over the gras part, the wheel almost overtook him underneath. So he lost "much speed" and reacted be leaning forward and accelerating (at least very sportive) for too long to catch up again... Edit: PS.: Some crazy mainboard/BMS firmware behaviour/failure is possible everytime and not to be excluded without closer examination of "real data", but as it looks chances are extremely high that here it's just riding over the "normal" wheels limits.
  16. 3 likes
    I assure you, it's possible to overlean a KingSong wheel. The Z10 implements tilt-back just like KingSong. When you reach the max speed it starts to tilt-back to slow you down. You can't turn it off like on Gotway. But if you aggressively lean into the wheel, it only takes a split second to over power the motor. So just like this Z10 episode, the KingSong wheels will also cutout. Maybe this is a bit of stereotyping, but I think the typical KingSong owner does not ride their wheel as aggressively as a Gotway or Z10 rider. And this is why cutouts are not reported much for those wheels.
  17. 3 likes
    I love my Skydio R1! It captures some amazing footage. I’ve already posted a few videos here in the past. Here’s some raw footage. Here’s a static shot of it following me. I’ve had one crash trail riding with Skydio. It hates small branches.
  18. 3 likes
    @Igor Rz At what speed was this? Doesn't look like the Z10's speed limit (45?) to me. Then he should not have been able to overlean the wheel that easily! That looks like a normal sporty acceleration at a still reasonable speed. It should have worked! Maybe it was some stupid current/whatever limiter throwing the rider off? I believe EUC BMSes have this disabled specifically so you won't just fall after a millisecond of undervoltage. Early EUCs had hat problem.
  19. 3 likes
    Dann ist das V8 zu schwach. Ab 25km/h bist du dann in Gefahr, mit etwas Pech auf der Fresse zu landen. Ist schon paar Leuten passiert. Ich finde das schlicht zu unsicher. Desweiteren klingt 30km/h viel, aber in der Realität ist das mindestens 5km/h zu langsam (und das V8 kann das nur unter Idealbedingungen mit voller Batterie). Man stellt fest, dass selbst die weniger dynamische wirkende Frau mittleren Alters auf dem Fahrrad gerne mal fast 30 fährt wenn sie wo hin will statt zum Spaß fährt, und andere Fahrradfahrer sind locker schneller. Ist immer wieder überraschend für mich, wie die Leute deutlich schneller sind als es aussieht. Radfahrer kannste dann weder überholen noch mit ihnen mithalten (z.B. Radtour mit Freunden, ich musste meinen 30km/h Piepser rausmachen bei der Gelegenheit damit ich nicht knapp zu langsam war. Und das war nur auf einen kieseligen Flussdamm!). Jeder meint am Anfang "über 25 reicht mir" (ging mir auch so!), und bald stellt man fest, alles unter 35km/h max ist eine deutliche Einschränkung, wozu das Ding nützlich und gut ist. Spielzeug vs. ernsthaft geniale neue Möglichkeit. Die V8 Batterie ist auch nicht sonderlich groß. Du kommst damit nicht allzu weit, und für dein Gewicht ist die Batterie auch ein Sicherheitsproblem. Zu wenig Bumms wenn du es wirklich bräuchtest. Das V8 ist 3 Jahre alt und kein schlechtes wheel, aber nicht zu empfehlen für Fahrer >75kg meiner Meinung nach. Es gibt inzwischen Neueres und Stärkeres (=sicherer) und deutlich Besseres. Das Z6/Z10 ist ein sehr schönes wheel, aber halt was Spezielles. Macht aber sicher viel Spass und wenn du gemähte Wiesen erwähnst, da ist das sicher super (andere können das auch, aber die Frage ist immer wie viel Spaß macht es). Wenn ich mich nicht sehr irre, dann wiegen beide Varianten gleich viel (die größere Kapazität kommt nur von stärkeren Batteriezellen, aber die Anzahl ist gleich). Nie unterschätzen dass man bald mehr Reichweite will als man anfangs glaubt. Eine typische Empfehlung für dich wäre z.B. ein Kingsong KS16S (gibt ne neue Version mit Knopf, der den Motor unterbricht, und besserem Metallgriff, Händler danach fragen) oder ein Inmotion V10/V10F. Und wenn du mehr ausgeben kannst/willst und mehr Performance willst, gibts die üblichen Kandidaten: Gotway msuperX, Kingsong KS18XL (18 Zöller), und bald kommen Gotway Nikola und Kingsong 16X (16-17 Zöller). Was gerade so aktuell und toll ist. Allgemein: Nimm das wheel das es dir antut. Meistens hat man heimlich schon eines im Auge. Das kommt nicht von ungefähr - Aussehen, Ergonomie, usw. spielt da eine (unbewusste) Rolle. Immer die größte Batterie nehmen, die du kriegen kannst. Nix schlimmer als viel Geld ausgeben für 80% dessen was möglich wäre. Dann steht man da und ärgert man sich, dass man sich nicht getraut hat. Gekostet hat es trotzdem viel. Lernen kannst du auf jedem wheel. Das falsche kaufen aus Angst ist letztlich nur rausgeworfenes Geld. Klar, kann man jemand anderen als Übungswheel verkaufen, aber man muss halt bald wechseln. Was solls? Zum Vergleich: Leute kaufen alle sonstigen Gefährte - Auto, Fahrrad, usw. - danach, was sie letztendlich fahren wollen.
  20. 2 likes
    You could see if 1RadWerkstatt have one, or can make one for you. But shipping could take some time. Don't think many resellers have many batteries in stock, due to cost and safety. And batteries don't tend to fail very often.
  21. 2 likes
    I hope they don't screw with the surface too much. Other than Grip tape, I'd except candy coating (epoxy with additives for abrasion/grip).
  22. 2 likes
    1000 miles in. Can't wait to see how much better I am after the next 1,000.
  23. 2 likes
    @Michael Tucker, no. Just about everything you stated as "should be possible" is not. If you had a stable platform (sitting on multiple wheels) and a separate "tilting motor" you could do the things you propose as possible, but you don't. Instead you have a platform suspended on an axle, and a single motor that rotates the wheel at varying accelerations/speeds to achieve all the performance attributes you called out as needing to be separated: balance, acceleration, and speed. Therefore, these attributes are intimately connected. A particular pedal angle being maintained (and the rider being kept from falling) is due to accelerometers/gyros in the wheel's case constantly monitoring its longitudinal angle, and as it moves by micro-degrees motor power is varied to correct. It's like a circus balancing act where the juggler puts a plate on a stick and the stick on his forehead, then moves continuously to keep that plate from falling off the stick. The way pedal angle changes is by accelerating or decelerating a tiny bit, and then using the new resulting angle as a new reference for "equilibrium." If the rider puts CG forward and the wheel does not immediately accelerate to maintain the angle/tilt, the system immediately loses equilibrium and the rider falls. No technological advancement will change this fact. It's physics, not technology. This is the same as the juggler example: the juggler can't decide to just not move past a certain point while balancing that plate...if he slows or stops the plate immediately falls. The juggler can move rapidly ahead of the plate to stop its movement, and even encourage it to move back the other way, but unfortunately the EUC rider (unlike the plate) has a will and a way to change her CG. As with the juggler and the plate, tiltback is the wheel accelerating slightly to get its own CG ahead of the rider's CG, which causes the case/pedals to tilt back, in an attempt to force the rider's CG to get behind the wheel so the wheel can stop accelerating or slow. Physics can't be cheated, but a rider can be strongly encouraged to move her CG backward in this manner.
  24. 2 likes
    Well then, it really was an overlean! Case closed. Thanks! I would have guessed he crossed the grass at no more than 30kph from the video.
  25. 2 likes
    98% of the time, the Inmotion Covers do come in the box. In this instance, it was our few remaining V5Fs, the cover stock for this model was depleted, ordered some replacement to be flown in.
  26. 2 likes
    why dont you just call Jason at ewheels and ask? I have never had a issue reaching out to him..
  27. 2 likes
    I'm glad I am not the only one. To be honest I find having discussions like this terribly difficult on the forum. People go off on all tangents, talking about respecting the wheels limits, how there is only so much power, only so much battery, dont lean heavily when near top speed, learn how the wheel works etc etc. and seem to miss/avoid the actual point in question. I know how to respect a wheel, I havent fallen from an overlean yet and I know not to take the pi$$ when I am already motoring on the thing but I was simply trying to find out why a wheel should shut down just because it cant spin any faster. Point being, a Tesla car doesnt just turn off the entire propulsion system when it reaches top speed. I totally get that an euc would lose its ability to balance (hence initiate an overlean), but not shut down.
  28. 2 likes
    Not a great quality pic (it's a still captured from video) but I did get a chance to ride my V5F at Yellowstone National Park. 8000 ft and 32 degrees F and it was wonderful. Wheel performed flawlessly and was so quiet that I had to rattle bear bells the whole time just to make sure I didn't run across any foraging Grizzlies.
  29. 2 likes
    Just a little tipp - if you do this record the voltages at begin of charge and after the charge, too. That's much more "meaningfull" than the reported charge %. With the state before the charge you'd have the chance to see sometimes how many full charge cycles you had. For Kingsong (67,2V) everything above 66,8V is 100% and everything below 50V is 0%. By this you have the additional benefit of getting some kind of "battery state" monitor - the max voltage after a full charge drops over time as cells age...
  30. 2 likes
    I have a little book where i write down my charge cycles, very german.
  31. 2 likes
    I understand that you want this data (you don't need it though). I am saying that making fields mandatory may not be the best way to get these data. Just saying. Do you have expertise or experience in designing questionnaires? Use "site:forum.electricunicycle.org" in a google search additionally to the keywords you are interested in to dig into the information wealth of this forum.
  32. 2 likes
    True, wheels that cut out at high speed is poor engineering. However, I think, most of us believe that modern wheels don't do that anymore.
  33. 2 likes
    I don't mean to be disrespectful, but I have the impression that you are not by any means a social scientist, or have a lot of expertise in conducting surveys. Why? Because you keep asking people for more response, as if representativity is attained when you reach a certain number of respondents. That's not how it works. More data does not necessarily mean better data. All it might do, is give you an more accurate profile of the average EUC-rider profile on this forum. It's highly unlikely that this is a good representation of the average euc-rider. There's probably a few different user-profiles, and the people on this forum probably cover a few of these (though some groups might be over-represented). So, to answer your question; how do you get better data? First, you need to think about what you actually want to know and why. What are your research questions? What hypotheses do you want to test? Perhaps it's more useful to make the study not just on euc, but also on hoverboard, e-scooters,... That way you learn about the differences between the users. Knowing 'the' euc user doesn't teach you anything without comparing it to anything else. Next you can make a survey. But don't do this alone, ask people with experience and expertise to do this. At least let some people proof-read it. Then: think of possibilities of gathering data. I'll give you a few examples: - One means is posting a survey on a forum (what you did here) - Post the survey on (popular) fora where there is a sub-forum that covers the topic (here you might find more youngsters) - Directly send your survey by e-mail to people who use an euc, asking them to fill it out, and to send it through to others they know who own and use an euc ('snowball-method'). It helps if you raffle a price (there might be euc-partners interested in helping with this, since they might be interested in the results); this can give you more responses and diminishes the risk of self-selection. - Face-to-face interviews: interview euc-users. Perhaps there might be other euc-users interested in helping with this, if you provide the survey-guidelines. - Ask sellers if they would be willing to send out an e-mail to buyers to ask for filling out the survey. -... But keep in mind; to ask for collaboration for the above, you really need a quality survey. And that's not what you have right now..
  34. 2 likes
    Actually, it's a cut out When you overlean (mostly by overloading power stage but sometimes also if you exceed max permissible tilt angle), controller cuts off power delivery to the motor. That's all. It just detects overload condition that could cause catastrophic failure to the controller power stage, so as a countermeasure it turns off all the transistors. There is no "soft" power limit, it's rather 0-1 situation.
  35. 2 likes
    Continue to provide the maximum it can give. This is the point I was trying to make. I understand batteries, BMS's, motors and how a wheel fundamentally works. What I couldn't (and still cant) grasp is why people keep referring to wheels 'cutting out'. It seems like an easy get-out to try and explain every fall there has ever been. What I think is actually happening in many cases is that a wheel is asking to be accelerated past the point it can maintain balance. Thus, the rider literally falls off the front because they are leaning foward. A bit like standing still on your feet and falling fowards. So I can accept people referring to this situation as 'overlean' as that is exactly what is happening. What I struggle with is people using the term 'cut out' as I am not convinced that is what is actually happening. That said, if it is then I dont feel this is a safe method to deal with an overlean situation. No wheel should just cut out unless there is a catastrophic battery failure/fire risk and the best remedy is to shut down all and every system.
  36. 2 likes
    Charge Doctor's are not available by now: My "normal" recommendation for battery care would be to, if possible never leave the wheel fully charged (too long, and especially not at high temperatures). So full charge before riding and inbetween leave it at some ~40%. But you have an Z10? Which is "dangerous" to leave for some time at lower charges because of Discharging the batteries too low is the other bad thing one can do to batteries... If you are experienced enough for this and dare, the following link could help against the vampire drain: With this mod and a nice (~5A) charger (Z10 BMS takes something up to 7A?) would enable one to establish nice charge cycles. Leave the wheel more or less as it is after riding - just maybe top a bit up to ~40% after the batteries cooled down (immediate charging after batteries got stressed is not recommended). Then before riding the final charge can be established. And the Z10 shows the single cell voltages?! So one can keep track of them to leave the batteries inbetween long enough on the charger, so they get (hopefully) nicely balanced.
  37. 2 likes
    If you can help me with a job I'll move from UK to America enjoy all that sunny riding weather , Shall i start packing👍
  38. 2 likes
    It's just "fusspoting" - but going on the limits a wheel is not cutting off, it's still delivering torque and trying to do what's possible - but if this torque is not enough anymore the lean of the rider cannot be balanced anymore and he overleans. A battery reserve would not really change anything. The a bit higher voltage of a fresh and full battery just sets the limit a bit higher, but still with enough burden (acceleration) at high enough speed there is no torque available anymore - that's no matter of power a battery could still deliver. Don't know the average KS rider, but imho the wheels are strong enough to need real accelerations for overleaning. In combination with the mandatory max speed tiltback that "chatches" many to most overleans. GWs with tilt back disabled just "motivates" too much riders to try to get up to max speed, until they learn that this is no constant and has to lead to an overlean... And Z10 are maybe just the weakest of the actual top wheels, as @Michael Tucker wrote?
  39. 2 likes
    Unfortunately I have not ridden the Santa Monica beach area this year yet! But from what @Dzlchef and @Jambo are saying, looks likes it's still very rideable. From Venice Beach Pier up to the Pacific Palisades, it's a great ride. Be sure to take the mini-detour up the California Incline. It's right off the bike path and at the top it offers a beautiful view of the whole oceanfront. It's a dedicated bike path separated from the cars by barricades. Here's the Google Map Pin for the entrance from the bike bath: https://goo.gl/maps/gktSPMz1iEaxJry47
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    Sure, it's possible. I have no hard evidence either way. But I can tell you that whether I'm riding my MSX or KS18XL, I'm not going to aggressively accelerate while at speed.
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    I do exactly the same thing. It feels weird if your feet are mismatched! As far as distance goes, I was at 35 KS miles Saturday and now up to 50 KS miles today. Each ride, I have less fatigue so the mileage is going up. I also went that distance on 20% battery (from 99% down to 79%). I was going to charge to 100% ahead of my ride to let the batteries balance, but I started charging too late... next week. So my guess of 45ish miles using 75% battery agreed with your long ride it sounds like. p.s. I didn't mess around with the ride mode. Everything was working so well, that I just enjoyed it. I found some branching and serpentine walkways at a sports complex, and was having fun taking different paths, ducking under trees, and accelerating through the straight sections.
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    @Marty Backe, while I do buy the theory that KS riders as a population are statistically less likely to ride aggressively, the problem with forums and YouTube, etc. is that statistics go out the window since it's the outliers who're more likely to be present and reporting their woes. It would only take a few anomalously aggressive KS riders who suffer a cut-out and post their videos or discussions before the number of reports of such cut-outs would seem just as high as it is for Gotway and others. So, isn't it also possible that KS is allowing for a larger safety margin that gives more time/torque/power for tilt-back to "succeed" before cutout, thereby contributing to the fact that we see a lot fewer cut-out reports for these wheels?
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    That's badass! Hope he and Miles do this ride! They will love it. Too good to pass up the opportunity to ride it with no cars like we had it (assuming that it's still closed to car traffic next weekend). Doesn't get much more epic than that was! 😎
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    Today was a rite of passage for me: the first "long-distance" ride. This was a 45.55-mile loop from my house, much of it on dedicated paved trails, with 1,588ft elevation gain/loss on the route. Max speed 24.1mph, average speed (not counting two breaks) 13.4mph. These are "real" distance and speeds per GPS routing/tracking. Here are the KingSong stats (keeping in mind that a "KingSong mile" is somehow a lot longer, and a "KingSong mph" is somehow a lot faster than the real thing): 53.5 miles traveled, average speed 15.4mph, max speed 25.1mph. Total KS mileage is now 228.5 for this wheel. I left home with a fully charged battery pack and arrived back 4 hours later with DarknessBot indicating 25% remaining battery as I rolled up to my garage. After 2 minutes of voltage recovery this had increased to 33%, after 10 minutes to 35%. The KingSong app on the other hand indicated 34% at arrival, 42% after 2 minutes of recovery, and 45% after 10 minutes. I'm guessing the discrepancy is due to the fact that KS runs cells down all the way to 3.0V, unlike other manufacturers, and DarknessBot is not accounting for that. In any case, this indicates great range, since 45 real miles with 1,600ft of climbing, and still having about 25-30% battery left is pretty good. This gives me confidence that I can expect a minimum of 50 real-world miles out of this wheel at my weight, at least in normal urban/suburban riding at moderate speeds. In some situations this may even stretch to 60 miles. For today's ride I had a pretty aggressive rearward calibration of about 4 degrees dialed in, and while this does help keep the feet better planted on the pedals (and weight distributed instead of too much on the balls of the feet), I've decided that this may be a bit too much for my comfort, so I did reset to 2 degrees rearward when I got home. The medium riding mode (which I was on today) seems pretty comfy overall, but I want to try the "soft" mode for a few days to see what that feels like. The main ergonomic problem on this ride was foot pain/numbness, and lifting one heel at a time while shifting some weight off the same foot, for about 10 seconds, provides enormous relief, but that relief is temporary and after 20 miles or so I was definitely ready for my lunch break. I had a small backpack with a sandwich and some water. Eventually the ankles were slightly strained, the feet were tingling, and during the second half of the ride I could feel that my legs were starting to get "trembly." I was mostly in a dead-lift stance, which provides excellent shock absorption over the unfamiliar and sometimes quite rough trails. It doesn't strain the back much, but the legs and glutes sure have to take a lot of tension for a long period of time. Wobbles are almost gone! Sometimes it wobbles just a bit, but it either dampens out on its own, or a slight shift in stance or speed fixes it. Some downhill wobbles in the last 10 miles, in part because I was definitely getting fatigued. When they do happen, wobbles don't feel as alarming and perhaps as a consequence of a different attitude toward them, they seem to just deal with themselves. Mounting is almost flawless now, with just one false start today. I still feel self-conscious when I feel observed and/or under time pressure to mount, though. I took one fall, due to a circumstance beyond my control: I was moving along at about 15-20mph and two bicycle riders were oncoming in the opposite direction. Nothing unusual so far, as the trails are clogged with people and riders today. However, these two riders were only paying attention to each other, riding side by side with heads turned toward each other and talking, and suddenly they apparently decided it was time for a U-turn on the trail, so they both veered into my path when I was maybe 20ft away, completely unaware of my approach. I had time to yell "watch ouuuuuuuttttttt!", was able to decelerate just a bit, and then I had one foot off the side trying to "skate" to a stop while veering away from a full side swipe collision. Just before hitting the rear wheel of one of the bikes, which was still basically crosswise on the trail, I let go of the wheel with the other foot and fell forward with one hand hitting the rear wheel of the bicycle. I avoided a full-on collision, the wheel didn't hit anything, and my right knee pad took the brunt of the actual fall. I'm guessing the wrist guards also did their thing, but I can't remember how hard they impacted. No damage except the right knee guard has a scuff in a corner and one of my shoes is scuffed up on top as well. The rider was apologetic and made sure I was OK, so in the end it was all good. In retrospect I wonder if I should have just run off the wheel and let it continue without me, but trying to stay with the wheel as long as possible allowed me to prevent 50lbs of electrified mass from plowing into the side of that bicycle...so maybe I did do the right thing. I think that's all I have to tell. This was fun, tiring, confidence-building, and at least incrementally skills-building.
  45. 2 likes
    It does not really - it just can't deliver enough torque anymore to keep one upright. Here is everything you never wanted to know about why wheels overlean Yes. The manufacturers could implement sound warnings in the firmware. But the rider has to regard the warning and stop leaning forward/brake. No. Just using a stronger wheel and accelerating at slower speeds make overleans go away...
  46. 2 likes
    Another 18.8km ride today https://euc.world/tour/575260614530142 Photos are included in the ride but i'll copy some here
  47. 2 likes
    Not too serius brake test euc vs e-scooter The first try with v5f
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    From the stills you made @Rehab1, I think it kinda explains why I could save my wheels reaction. As you pointed out he has a forward lean out passed the wheel. But when he starts to lean further to accelerate the wheel cannot keep up. When I ride I partly lean partly push with my foot, as if I am standing on my toes. This mean I don't tend to risk overlean as much, however the wheel will kick in with tiltback, that kinda surprised me as I done that level of acceleration before, but at 80-95% battery capacity. Learn how to ride in snowy condition helped me not to lean out passed the wheel as much as you want to have your center of gravaty if you get what mean as straight above the wheel at all times. This helps to prevent wheel from sliding away under you in slippery conditions (snow, gravel, loose sand, sand on top of hard surface, ice, mud, wet leaves, road markings in the wet, wet grass, just to mention a few on top of my head😁).
  49. 2 likes
    Glad he is ok. My 2 cents: after your friend passed the elderly couple he transitioned to the grass then onto the road. He appeared off balance through that entire sequence and never gained full control.
  50. 2 likes
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