After battling some range anxiety earlier this summer, I decided to run a controlled experiment on my Zero SR/F 2020 premium, to see what exactly happens when you run out of battery power. I also wanted to check the real max range, as I was hit by that magic charge error earlier, which would give me only about 80km range, and wanted to make sure it was truly fixed after having it serviced.
Also, I am the kind of control freak who does not want to leave anything to the unknown, and although there has been some comments on this topic in other parts of these forums, I wanted to see what happened by myself.
So, I started off at 100% charge, then I drove the motorbike in various conditions. City, freeway, with passenger and without. Always driving in Sports mode. Over a period of about 1-2 weeks. Finally, today I reached 11% battery charge and decided to drive around where I live to drain the rest. At the end I drove in smaller and smaller circles to ensure I was never too far from a charging point. Being prepared to push it in the end, if I had to.
First of all, quite impressed with the final range. I got 206km in the end before hitting 0% charge, making no efforts at all to drive in an eco friendly way. A majority of my rides were high speed rides on the freeway with my gf as a passenger. I am quite heavy at nearly 100kg, gf 50kg, and we drove up many steep hills. I also have three cases on the bike, so it has to fight some extra wind resistance due to the larger profile. So, the bike surely had to do some real work. And between runs it was parked for quite long time, presumably also leaking a little bit charge.
It was quite tedious to drain the last 5% or so, as I wanted to make sure I would not end up in a steep uphill towards the charge point, should it just finally die suddenly. But it all went without drama, and this is what I found:
- When the bike went below 10%, I noticed the acceleration power started to vanish. It was not sudden, but a slow transition from full to low power. At first I would only notice it if I maxed the throttle, and the MC would kind of give up after delivering the first raw acceleration. The give up point was first at about 60 km/h, and as I gradually went lower on juice, the weakness point had gone all the way down to 0km/h.
- Once I reached 0%, there was no sudden battery saving mode kicking in. The acceleration kept being weaker, but I had no problem accelerating up to 80 km/h, given some patience. It did continue to weaken after the 0% mark though.
- As I was driving in a 40km zone, near my home in the city center, I did not dare to check the max speed much. But after driving about 6 km past the 0% point, I decided to do a final race to check the max speed. I found the MC really struggled to accelerate fast now, it now maxed out at about 60km/h. Although, if I was in a freeway, I might have been able to push it over this speed. I could only push it for a short period of time, due to the 40km/h speed limit.
- Having gone 6km over the 0% point, I was starting to get a bit bored with the test as I had been driving around in circles for about 10km already, it was getting cold and I didnt really want to get off and push the MC the last bit in the end. So, I ended it there. Although it would have been interesting to see just how much safety margin there is, and what exactly happens once you really run out of juice. I would not be surprised if the MC could go a lot further while in this low power mode though.
In the end I was quite happy with the result. The engineer servicing the MC had got rid of the magic charge bug for sure, at least for now. And, I learned the bike will not suddenly die at 0%, also wont suddenly become weak in an instant. It will allow you some wiggle room in the end. Although, you'd probably not want to be on a high speed road at the moment you reach 0%, as you will surely become a dangerous roadblock driving at around ~60km/h. I suppose some might prefer it to retain max power until really suddenly dead (my previous electric scooter was like that), but, for me the current way with gradually lower max power is quite satisfactory (as long as it is induced at the correct point, and not too early, as it likely will if you have that magic charge problem I had before)
Anyway, hope this was useful for someone.