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Keith last won the day on September 8 2016

Keith had the most liked content!

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About Keith

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    Veteran Member
  • Birthday 07/04/1955

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    Surrey, UK
  • Interests
    Radio Control aircraft, photography, Malta.

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  1. Absolute bollocks. That is a hangover from NiCad Cells. There is NO memory effect on Lithium Ion as @FreeRide has already said. All that will happen is the batteries will be aged faster if fully cycled. Fully discharging a pack also risks real damage to some cells if they are already lower than others, by taking them below their safe minimum voltage or even reverse charging them. The only thing preventing them being seriously damaged by being completely discharged is that the BMS idea of fully discharged is usually still with 10% or 20% or even more capacity left in the battery to prevent them actually fully discharging. i would love to see a copy of where in a Ninebot user guide it tells you that you must fully discharge the cells?
  2. It’s hidden, not deleted. New user using a spoofed email address from St. Helena, but posting from Ireland whilst hiding his location. Also hiding details on YouTube. We rely on trust on this forum as we have had some pretty awful behaviour (which is why new users cannot P.M. either) so your behaviour doesn’t give us any trust. Give us a real email address and location and I’ll unhide your post. Only Moderators see that email address. Or, of course you can stay anonymous and have every one of your posts moderated.
  3. You haven’t thought out properly how an EUC balances and works. This just is not possible without faceplanting the rider. To reiterate what has been said before: the primary function of an EUC is to balance and that is ALL the electronics are trying to do. That this causes you, if you lean forward, to accelerate is a happy byproduct of that function. Anything you do to “reduce power”, brake, or anything else, like restrict maximum speed, control traction, etc, etc, is fundamentally going to bugger up balancing. Not to mention that they still haven’t been able to completely eliminate such oscillations due to poor skills by the operator in much, much more mature technologies such as motorbikes and planes
  4. Keith

    Used Rockwheel

    There is no lead in Lithium Ion batteries - there is, unsurprisingly, Lithium. We wouldn’t be riding EUC’s if the battery technology hadn’t advanced beyond lead acid batteries! I did not say “it can only be stored at 40% to 60% power”. I said leaving it fully charged or fully discharged for long periods is harmful. The word “should” in the English language means something is advisable. Something as expensive as a Tesla car (which owners have paid very many thousands for the battery in) has systems and software that does its damnedest to prevent the user from abusing the battery and indeed doesn’t fully charge the battery if possible. EUC’s are still really at the early adopter phase and and the user needs to have something of an understanding of all the technologies involved to ride them safely.
  5. Now all you need to do is get sponsorship from all those companies and you’ll be able afford a ?Z10 or KS-18 ?
  6. That might just be because not a it a lot of riders crash and fall off anything like as much as your copious previous posts suggest you do. I’m surprised any part of you still works? Of course neither do a lot of riders ride around all the time at less than walking speed which must put a lot of strain on the hips as twisting the hips is the only way to balance riding that slowly ?
  7. Yeh, spoken by someone who has never faceplanted due to a sudden failure. We had a guy like you a couple of years ago, called us all wimps, “All you need to know is how fall!” then came off riding at speed along a lakeside beach wearing just shorts. He did at least have the decency to publish the photos of his injuries afterwards.
  8. Keith

    36er unicycling at CicLAvia 9.30.18

    Moved this to off topic. It fails to be an “Other non self balancing PEV” on EVERY level.
  9. Keith

    MSX 100v VS MSX 84v

    This can be soooo wrong for electric motors because you are completely ignoring efficiency. The losses in any electric power chain are I squared R losses I.e. the bit that ends up wasted as heat. It is current that generates heat, not voltage, that is why very high voltage power lines are used to deliver electricity over long distances, the power doesn’t get wasted heating up the wires. Assuming that at a given speed and weight rider on a given day and place (I.e. all things equal) then the EUC will require a certain power consumption and given that P=VI then a higher voltage will require correspondingly less current which means correspondingly less losses due to heat so the 100V machine ought to have better range from the same Wh size pack, even though it will have less Ah then the lower volt pack. However this is in an ideal world where the motor has been correctly wound to give its best efficiency at cruising speed - which Gotway may, or may not, have done? Because I don’t know the characteristics of the two motors used, another area of uncertainty is this cruising speed. Electric motors are at the most efficient running (at full power) at around 80% of there no load (or absolutely maximum) speed, efficiency falls off rapidly if run below 50% of no load at full power (say when speed is limited by going up a very steep hill for example) that loss of efficiency again manifests itself as heat. I know we never run at full power on EUC’s but the theory holds for example if you are using half power and going at less than 25% no load speed you are again in an area of poor efficiency. If the 100V and 84V EUC’s both use exactly the same motor with the same RPM/V (Kv) then, cruising at say 15MPH on both will see the 100V machine running at a much lower efficiency as it is running at a much lower percentage of its higher no load speed I.e. you would have to run it fast to get any efficiency out of it. However if it has a lower Kv motor such that it’s no load speed is no higher than the 84V machine then it will be more efficient as it will consume less current for a given power output at a given speed. This is a long winded way of saying that only a back to back test of both machines by the same rider (or two of the same weight and riding style) will really show which works better.
  10. Keith

    Ninebot S1 Battery Fuse

    To start with, the motor is a max 1000W motor at nominally 54V which is peaks of 18.5Amps which it can easily hit, or exceed, when standing still as that is when the back e.m.f. from the motor is zero and the only current limiter is the tiny resistance of the motor windings. So a 15 Amp fuse is going to blow easily - that may be all the problem you have? Secondly, those fuses, on the BMS, are last ditch attempts to prevent a fire on chronic overload. I.e. they are not meant to be replaceable so should only fail under way beyond maximum load. My guess, and it is purely a guess as I don’t have the specifications is that those fuses should be at least 30 amp and possibly more than double that. Your description of the fault suggests you did overload it heavily (tilt it to get it to drive hard and prevent it moving) so the first problem is that it is possible something else failed before the BMS fuse, most likely one or more of the output FET’s on the main board. They tend to fail short circuit so would explain the BMS fuse going as well. Motor windings could also have failed or heated enough to short coils through burnt insulation which would then probably kill FET’s as well. This is less likely though. The only real test you can easily do, short of powering the motor with a new board or using an impedance meter is to test across every combination of two of the three motor power wires. Every combination should have the same resistance, but this is such a low figure you may not be able to tell a good coil from a short. If you can fit a fuse that is high enough not to blow, failed FET’s, if they have occurred, should manifest as the wheel being to stiff to turn when powered up but free when powered off.
  11. Keith

    V10F wheel need balancing?

    I had a private bet with myself that someone would say the above. A car front wheel is hanging out at the end of a steering arm so an imbalance at the rim of the wheel will, of course, pull the steering left/right as it is happening at a considerable distance from the wheels steering pivot point. And yes, wheel balancing equipment can detect which side of of a much wider car wheel is out of balance. However, the imbalance cannot possibly be more than an inch or so from the centre line of a 16” wheel. Even chronically out of balance it would have a tiny sideways pull.
  12. Perhaps @jojo33 is the best person to answer this?
  13. Keith

    V10F wheel need balancing?

    Yes, everyone has! If the wobbling is up and down or like a vibration it might be wheel imbalance. However if, as I suspect, it is a side to side movement it is impossible for the wheel to generate that, it has to be the rider. For a new rider there seems to be a “wobble barrier” a speed where wobbling occurs and can get worst as you go faster, possibly throwing you off. Untrained muscles, feet too far back (centring your feet on the peddles instead of centring your mass over the middle of the wheel) just nerves as you go faster, all seem to play a part yet it seems to just go away by itself almost as you gain experience. Search on “wobble” to see just how much it is discussed: https://forum.electricunicycle.org/search/?q=Wobble or just this recent post:
  14. Welcome to the forum. However please ensure you post in the correct section - the general discussion section is for EUC’s. I’ve moved your post to the Ninebot Mini section where it belongs. Having said that, and bearing in mind you are in London, I have not got a clue what you are talking about, the spelling mistakes are so many that I have absolutely no idea what you are asking? How, for example, can you being tall have anything to do with using a remote?