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    Why are DC-DC buck converters so limited?

    Stepping down voltage is indeed much simpler than using a DC to DC conversation. A simple zener diode or a zener diode driving a power transistor, would be the simplest technique. The circuit is placed in seriess with the load and it's effective resistance changes , so that the voltage accross...
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    Orbea Katu E 10 LR 2017 - Electric Bike

    .. small wheels have a number of advantages in an urban setting. They are stronger, more robust, contain less inertia so better in stop go motion. The extra width of those wheels, while probably impacting range to an extent , make for a more comfortable ride. The smaller size makes the overall...
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    Battery Cutting Out

    Yes see Neath s posting below. Actually the best way to have treated your lithium ion battery is not to let it discharge fully but to charge it up after each use. Leaving it all winter in a discharged state not good also. Whether leaving it charging for a winter is good or bad would have...
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    Bosch climbing speed

    ... It's always worth reminding that there are people with real medical problems .
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    Battery Cutting Out

    .. with the additional information you now have re read Neath s post. Your battery pack has 40 cells, in 4 parallel rows each of 10 cells in series. Note that even when fully charged one of the paralleled groups is charging to a lower level than the rest. .. if might only be 0.2v but that is...
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    Brexit, for once some facts.

    ... Ooh another country music fan...
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    Bosch climbing speed

    ... What Woosh was saying is that the majority of the energy from the battery is converted into heat, if the motor is struggling at low revs. But that e heat is being generated in the motor not the battery. The battery don't know whether the current it's producing is going into motion or...
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    Bike racks.

    .. meets all the requirements, and with a 60 kg max well capable of two laden ebikes...
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    Brexit, for once some facts.

    Brexit coming by Stealth... Not important in the great scheme of things, but interesting nonetheless... Up until last Wednesday I was able to access via a sky nowtv box content from the UK centre. while present in the republic of Ireland .. I was a grey user,.. in that I had always purchased...
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    Brexit, for once some facts.

    Me chuckle person too.
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    Bike racks.

    .. Halfords have a lower cost own brand as well as a lower cost Thule
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    i did not think i was that fast

    ... That's a boy what takes his weetabix..
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    Bosch climbing speed

    .. thanks that is an excellent factual post, certainly the hub motor driven by the bigger voltage wins in any case.and performs better if the wheel diameter is reduced. The simulator is a very nice piece of software. Were the Bosch equipped with a 48v battery, and an assurance that the motor...
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    Brexit, for once some facts.

    If you liked what you were doing it would be a hobby not work, and why would anyone pay you?.. shades of Mark twain. The trick in life is to derive satisfaction in doing what you have to do , or in being where you want to be
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    Brexit, for once some facts.

    For once I am inclined to agree with Thrump about calling the persons who commit these acts as losers . Unfortunately the actions of the mainstream media are turning this loser into a winner. Out of a non descript life he has achieved international celebrity status. For the cost of one life...
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    Brexit, for once some facts.

    Almost certainly one of the UK registered airlines will attempt to take over these routes so, but they will by definition be trying to muscle in against a really dominant player, and will remain a niche player. What rights will they get to fly into European airports if they are not prepared...
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    Bosch climbing speed

    Fair point. , But do hub motors not already allow this? I would not be advocating a full publish of their software parameters. Just a minor mod by which the amount of assistance was increased step by step from the current max of 3 times human effort to let's say 30 times,. But with the...
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    Bosch climbing speed

    It is regrettable. That Bosch and other torque sensing motor vendors don't allow the torque multiplier be altered by the user, they could for instance change the multiplier , adjustment increment up to 99. ,. And still be compliant with the law. .. it would only be a software mod,and would...
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    Bosch climbing speed

    ... That figure presumably is the peak efficiency, when the motor is running at its designed speed, if the motor were stalled , for instance, it will still be consuming the same (or more ) electrical power but its mechanical power out is zero and all the electrical power appears as heat. If...
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    Bosch climbing speed

    ... I can accept the majority of these figures without question! However the efficiency ones , I have difficulty with. If the hub motors designed speed is 250 rpm, thence it will be rotating at 40% of designed speed and. I would suggest ,that an efficiency of 70% would under those conditions...