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    Reality check

    The bottpm-line question is, would a professional with the right tools need two and a half hours to reach the conclusion that a hub motor does in fact work? Just how long does it take to try every combination of wires?

    This is the full entry logs for the work done by the ebike shop (with in-house techs) I used. I wanted them to diagnose my hub motor and see why it wasn't working. Now, where I come from $80 an hour is a lot of money but I'm willing to pay it if the time is well spent. So the question I have is, where you come from (the ebike world), does anything seem unreasonable or unlikely about a circumstance where this amount of time is required for this effort? Is this the typical amount of time it would take any ebike professional tech to accomplish this? Is "2.5 hours" or "two half hours" closer to what you'd expect?

    November 15, 2018 - Customer brought in a rear wheel hub motor, battery, controller and throttle, parts from 24V X-treme eMtb, off of bike frame (bought 2 years ago). Throttle is not original or from X-treme, customer thinks battery and throttle are okay. Please diagnose.

    November 26, 2018 - Technician MC connected up motor, controller, throttle and 24V surrogate batteries - does not work. Tested motor with Lenz law and tested okay. Li battery is sitting at 28.5V, unable to load test. Negative battery lead on controller is worn, possibly damaged. Throttle wires have been cut and repaired, and have tape around them. Is 3 pin throttle; do not have another 24V 3 pin throttle to test. Tried connecting 3 of 7 pins from another throttle but does not work. Recommend replacing controller and throttle. 2.5+ hrs.

    (the rest is parts, 1 controller and 1 throttle.)

    Is this reasonable or excessive time?
    Last edited by Jim Worley; 1 week ago. Reason: first line question

    #2
    Originally posted by Jim Worley View Post
    The bottpm-line question is, would a professional with the right tools need two and a half hours to reach the conclusion that a hub motor does in fact work? Just how long does it take to try every combination of wires?

    This is the full entry logs for the work done by the ebike shop (with in-house techs) I used. I wanted them to diagnose my hub motor and see why it wasn't working. Now, where I come from $80 an hour is a lot of money but I'm willing to pay it if the time is well spent. So the question I have is, where you come from (the ebike world), does anything seem unreasonable or unlikely about a circumstance where this amount of time is required for this effort? Is this the typical amount of time it would take any ebike professional tech to accomplish this? Is "2.5 hours" or "two half hours" closer to what you'd expect?

    November 15, 2018 - Customer brought in a rear wheel hub motor, battery, controller and throttle, parts from 24V X-treme eMtb, off of bike frame (bought 2 years ago). Throttle is not original or from X-treme, customer thinks battery and throttle are okay. Please diagnose.

    November 26, 2018 - Technician MC connected up motor, controller, throttle and 24V surrogate batteries - does not work. Tested motor with Lenz law and tested okay. Li battery is sitting at 28.5V, unable to load test. Negative battery lead on controller is worn, possibly damaged. Throttle wires have been cut and repaired, and have tape around them. Is 3 pin throttle; do not have another 24V 3 pin throttle to test. Tried connecting 3 of 7 pins from another throttle but does not work. Recommend replacing controller and throttle. 2.5+ hrs.

    (the rest is parts, 1 controller and 1 throttle.)

    Is this reasonable or excessive time?
    I don’t find that unreasonable at all. Things often take longer than expected when you actually get in there & execute to completion.

    *Some* people would opine that a lot of ebike parts are considered throwaway (I would set aside as a source of spare parts) because the new parts are not terribly expensive.

    Hindsight being 20/20, you could have immediately given up on this motor, purchased an identical one, and fixed your system by installing a new motor. Maybe not the most economical repair, but this is a fast, direct path to get you back on the road. Later on down the road, the new motor may have an issue where the spare, faulty motor *could* provide the parts needed to get one of these motors fully functional.

    If you are willing to mess with it yourself, the $80 hourly rate is no longer an issue and you have a chance to fix it yourself for only the cost of parts and any tooling that you need for the job. If you have one specific type of motor that you use, learning how to repair it yourself could make future repairs faster & more economical.

    Comment


    • MoneyPit
      MoneyPit commented
      Editing a comment
      ^^^ what he said. Always keep spare parts handy. Replace and harvest for spares down the road. Two days ago the spare crankset I kept in case of a rainy day came out of the shipping wrap and went on my bike due to a seized bolt when trying to change a chainring. Bolt froze at 6 am and I made it to work by 7:30.

      Its either that, or resign yourself to pay other people for their time and labor. And they don't know your bike as well as you do.

    • commuter ebikes
      commuter ebikes commented
      Editing a comment
      I used the exact same electrical system on all five of my ebikes, so I only have to master (as if!) one motor, controller, display, battery, wiring harness, throttle and 3-speed switch. And the spare parts (e.g. bearings, axles, Hall sensors) fit on any of the bikes.

      I imagine one day about 40 years from now when so many things would have failed that I will hopefully be able to barely cannibalize enough good parts from 5 old ebikes in order to make one bike that works.

    #3
    Would I find $200 acceptable for a simple diagnosis? No, but I would have started on the internet and determined how to check it myself to start with. Is it unexpected for it to take 2.5 hours for a shop to diagnose a problem where the system has been cut and modified? Not really.

    Comment


      #4
      The diagnostician probably spent tens of thousands of dollars on his education and thousands of hours of hard work to get the knowledge and experience that he has. Looking at it that way, $200 is a bargain!

      Comment


        #5
        Decades ago, when asked if I was taking too much time to accomplish a task my response was often to simply step back from the task and say "please show me how to do this more quickly - I'm truly and sincerely eager to learn"

        My more flip response might be "How bad do you want this? That's how bad you will get it" ...

        Comment


          #6
          Originally posted by AZguy View Post
          Decades ago, when asked if I was taking too much time to accomplish a task my response was often to simply step back from the task and say "please show me how to do this more quickly - I'm truly and sincerely eager to learn"

          My more flip response might be "How bad do you want this? That's how bad you will get it" ...
          Do it right or don't do it at all. If they rush you and cause you to skip steps so that it has to be redone, the task will really take a long time.

          Comment


          • AZguy
            AZguy commented
            Editing a comment
            I'm fortunate enough that I can tell people how long something will take and if they don't like it walk away from it.... or at least let them now what they'll get out of a rush job if they are willing to live with the foibles the rush will create *and* I still feel like doing it...
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