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The reason why there are speed warnings and tilt-backs (even tilt-forward for my gotway Msuper) is to avoid that the rider falls forward while accelerating because the engine, the converter cannot deliver that high CURRENT, while he is able to work at that voltage. But strange enough, the warnings, the alarms and tilt-backs depend from speed (which is proportional with the voltage) instead of current. You would still say: so what? Well, if you are climbing a steep hill of 35 degrees and you are 120kg and you accelerate very fast on this hill from 0 to 20km/h. You wouldn't even hear a warning before falling because your speed is OK (less than 20km/h) but the engine and the converter cannot deliver that high current: current is proportional with the load (=weight, inclination and accelaration). voltage is proportional with the speed (motor speed and unicycle speed). Also for braking, once I had braked heavily and my gotway msuper did a tilt-forward, to make me clear that he cannot brake that fast. Again without warning. since my speed was ok, besides I was braking so of course there will be no warnings for brakings: but it should. I became a little unstable due to tilt forward during braking but again this is a current and load issue not a speed and voltage issue. why don't they focus to current to make the unicycle safer. The voltage nearly rests the same for all moments: 52-68 volt:empty, full, high speed, low speed, braking, accelerating. always between 52-68. But the current can go from minus 50 amperes to plus 50 amperes: a huge difference and the most restricting factor for the capabilities of the product. If we look at the progression in the car industry in the last 2 centuries, one can give an example for safe braking to compare with the safe accelerating on the euc's. They make an ABS system to make you brake safer. They don't say: "you are braking, your intention is to stop, and stopping is safe, so you are in the good way. you don't need a ABS. you may brake and slip when you brake from 200km/h to 0km/h in a rainy environment and due to slipping you may make an accident and die." But the engineers of euc do still need time to make the euc safer, not slower, safer by inventing the current warning system. No? I think the reason is: current can change instantly (accelerating from zero or hard braking at high speed) and warnings should not have an impact by that time, while speed increases slowly (e.g. 3 seconds from 0 to 30km/h), then it has sense to send an alarm at 25km/h and by the time you hear it and you stop accelerating you ride already 35km/h. If the warning would be at 33km/h, by the time you hear the alarm you would be at 44km/h and you would have fallen. But for people want to accelerate slowly the alarms at low speed levels is not relevant. Engineers... am I correct?
I have a Gotway MCM4 which is using Panasonic NCR18650PF battery cells, like lots of recent Gotway and Kingsong wheels. I have found these informations which indicate that fast charging (5A or 3,5A - 4A using 2 chargers) may not be good for 340Wh and smaller battery packs. General NCR18650 series : cell at 10°C or below : charge at 0,35C = 1,89 A (2P / 340Wh) ---- MAX charging is 0,7C = 3,78A (2P / 340Wh) NCR18650PF : standard is 0,5C = 2,7A between 10°C and 45°C For general information as I dont know if these are used in wheels : NCR18650B (used before 18650PF) : 0,25C at 10°C and below, MAX is 0,5C (same apply for NCR18650F) So it would be recommended to check a wheel battery cell specs before applying a higher charge current as wheel as the room temperature. And maybe do not put to charge just after riding if it too hot or cold outside.