I have an issue with my Nik ... all details to be found in the mailcon below fyi. Comments and ideas welcome :-)
By the way, this is one serious use of EUCWorld App ... and I personally like the interoperability with relive as to be seen in the beginning of the video. In the free version not the best resolution, anyway good enough to visualize the track log.
<<<<< mail to
myewheel.com ... latest first ...
Hi Andrey,
thank you for your answer. I completely disagree. Your speculations and ideas do not match the real life experience, scientific standards and my description as of my complaint at all. Unfortunately I am left back with the impression that you want to talk yourself out of the liabilities from your warranty you sold to me together with the Nikola. Please let's start a second try. Of course I have evidence for every detail. Take your time, ease back, read and watch the video I made for you and the community :-).
1. Voltage loss: Since there are three battery packs an overall voltage loss of 1.6 V refers to a possible calculated loss in a single pack of up to 4.8 V since the good packs take tasks of the bad pack while the bad pack gets hot. If there is just one defective cell - representing an initial loss of 4.2 V - it's neighbours have to work harder, will definitely get hot and might set the whole pack and finally my house on fire. That is an unacceptable risk and the most common reason for burning Li Ion Packs as you will for sure know.
2. Charging: I always charge all of my wheels overnight to leave enough time for thorough balancing. I tried all of my chargers, i.e. the Nik's stock charger, the RS' stock charger and a third party charger with adjustable Amps and balancing time. All of the chargers deliver 100.8V measured at the charging plug. I also used EUC World app along with a wireles socket controllable by the app and documented each charging since I received the wheel. In the beginning I did hope that this voltage loss will go away when batteries are kind of calibrated after first two or three charging cycles. Nevertheless, behaviour did not change. Always charging to 100 % does not at all affect battery life ... I have other wheels and Esk8s with 800+ cycles still delivering more than 95 % of their original capacity. Not charging to 100 % and thus not balancing the cells instead may very well shorten battery life.
3. Problem with the lights: You mention a common Nikola issue but your description does not match the issue I described in my complaint. The problem still occured after reboot and on the contrary to your tale, light started by itself after some time of driving. What you call an issue is a feature and not a bug and can easily be reproduced if you switch on the Nik when it is not upright. I consider this as a warning to not mount the wheel until it balances itself.
4. Temperature vs. speed: In real life when climbing all of my wheels get hotter at speed and cool down substantially when slowing down during the incline. Maybe you suppose a creeping velocity ... I never did this. And none of the wheels I have ever ridden did perform a cutout after overheat warning. The worst I ever experienced was soft tiltback after warning thus enabling me to let the wheel cool down. Please see the following EUC World log, proving that the temerature at the overheat track started rising continously from turning on the wheel until it cut out.
Possible reasons - one ore more of them - for my Nik's odd behaviour are:
- bad battery pack or defective single cell
- bad bluetooth board reporting false values
- defective board not powering up the fan
- defective fan
Feel free to add more ideas.
To help you matching the data from my track logs I provide hereafter I also made a video of the second reference trip. It is uncut until the camera battery dies, enabling you to match the video scene with the temperature and speed recordings of the log ... therefore a longer clip. I narrated the respective speeds. Unfortunately this is not very well hearable since camera was directly mounted to wheel ... sorry for that.
Log of overheat track:
https://euc.world/tour/606545294446220Log of reference track with the same weather conditions:
https://euc.world/tour/606638653400240Log of an additional steep incline immediately after reference track:
https://euc.world/tour/606638653859149Video of the reference track:
https://youtu.be/0WhawndMFCE presumably online by 8 p.m. CET today.
Please take my complaint seriously and cooperate with me while settling. Since the reference tour did not produce any issues I am prepared to start whith the least cost intensive solution and suggest sending me a perfectly working new bluetooth board and a fan to replace and see what voltage and temperature are like. At that occasion I will measure the voltages of the individual battery packs before and after charging. Maybe we can identify the culprit that way. If all batteries are in good shape when individually measured and there is still a temperature issue I will demand a replacement mainboard, if a battery pack is bad when measured I will demand a replacement battery pack.
Please be aware that I intend get this settled within the lifetime of the warranty. I therefore set a local business partner of my company in BCC to keep him informed and ready to act as I will come to the conclusion that his stepping in will be necessary. I have no warranty contract with the manufacturer but with myewheel and I am not interrested in topics the manufacturer will not accept as put forward in your recent reply. If the wheel starts burning due to battery problems you and me will have to settle the consequences of the damage.
Let us cooperate as fair business partners. I would love to keep recommending your company to all of the people asking me details about my wheels and where to get one too.
Â
Cheers - Thomas
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Gesendet:Â Mittwoch, 02. Februar 2022 um 08:02 Uhr
Von:Â "My EWheel" <
info@myewheel.com>
An:Â "thomasPan" <thomaspan>
Betreff:Â Re: My "Gotway Nikola Plus" - complaint
Hi Thomas,
If there is a problem with the battery, the voltage loss should be at least 3.15V as the voltage of one of the cells in the pack. The fact that the battery charges up to 99.2V can be due to many reasons, but in general, this voltage seems normal. Basically, when charging the charger reaches almost the maximum charging capacity and the light turns green, but it does not mean that the charging process is finished. Although it glows green, the charger continues to charge the battery, but now much slower in terms of security to protect the pack from overcharging. If you leave the charger on a green lamp for longer, you will notice that the voltage continues to rise. Also, the maximum charging voltage depends on many other factors and a difference of 1 volt from the absolute maximum (100.8V) is considered normal. In general, it is not recommended for the battery life to always charge the wheel to 100% because this shortens the battery life dramatically. I recommend you to use a multimeter to measure the chargers that you have, how many volts the output has, so you can find out with the specific charger what is the absolute maximum that you can achieve. Keep in mind that the chargers themselves sometimes do not deliver the maximum that the battery has according to the specification (100.8V). The manufacturer will not accept as a defect a difference of less than 3.15V on the battery.
Regarding the problem with the lights, this is a common Nikola issue. The board needs to be restarted. To restart, simply turn on the wheel and lift it with your hands and tilt it until the wheel turns off (simulate cutoff). Sometimes you may need to repeat this exercise, but it will certainly solve the problem with the lights.
When climbing, low speed is the main cause of overheating. The lower the speed, the greater the load on the motor and this is the reason for the high temperature reached. My advice is when taking such climbs to watch the application to avoid overheating. Do an experiment to pass the same place with greater speed and you will see that the temperature will be different. You've probably seen videos of Shermans burning when climbing slopes at very low speeds.
...
Best Regards,
  Andrey
...
On Tue, Feb 1, 2022 at 6:37 PM thomasPan <thomaspan> wrote:
Hi Andrey,
there is an issue with the Nik. From the beginning since last August it was not possible to completely charge it. The stock charger endet charging and the wheel's voltage as of EUCWorld App was 99.2 or 99.8 V - should be 100.8V - and the App showed it as 100 %, the display of the wheel showed 100 V. Same with the charger of my RS and a third party charger derlivering 4Â Amps.Â
Example:Â
https://photos.app.goo.gl/tyS56MTsJC3Kd5RF6 ... there are lots of similar pics i took after each recharging.
In general - not just bechause oft those reported fire hazards with Gotway wheels - I am a bit concerned about the health of the battery packs and of course do not want to set my house on fire. So I ask for your assistance to sort this out. Already intented to report this in october but had to go for business journey and there was literally no time to sit down and reach out to you. Wheel has been charged maybe 10 times now and never reached more than 100.1 V.Â
Apart from the battery issue there are some new findings as of last week and today ... maybe related, maybe not. The other night I went on a nightride, switched the wheel on and the circling leds showed just red, no rgb and the main light did not switch on. Restarted the wheel several times, no difference. Tried to switch light via EUCWorld App and Begode App ... not working. Since I had a bright light mounted on my helmet I started riding anyway and tried the wheel's light some minutes later, which worked.
Yesterday at an outside temperature of 2°C I did a rather steep incline for 5 km with about 20 kph and the board temperature went to 49°C, - no major voltage sag ... so far pretty good. Today on the same track after 1 km the board temperature all over sudden was 76°C as reported by EUCWorld App and Voltage dropped from 95.4 V to 88.6 V ...Â
https://photos.app.goo.gl/tDD5ryV1yoPEqTee7. Just had the warning sound from the app since beeper is almost unhearable, wheel itself had no tiltback. Lucky me i stopped and the wheel cutout ... fell on its nose and damaged the plastic housing of the front.Â
If it was not theat cutout a creepy bluetooth board might also be in suspect ... or a defective fan. But now I am even more concerned about battery health.
As before with the RS I am prepared to open the wheel on your command so that the guarantee is not void by my actions :-)
Pls help asap! I desperately need the wheel ... of course to save the RS in prevalent weather conditions :-)Â ....