Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[SRich]

I have a 2015 Zero S and have put 25k miles on it. It is my daily commuter, so I ride it as much as possible year round as long as temperatures are above 35 degrees and no snow or ice(I live in Utah) . For the past couple of years,  I have noticed that the outside temperature at which the speed starts to be limited has been rising each year. Last year anything below 50 degrees seemed to limit the speed usually to about 70 miles an hour.  This is typically about my max speed I travel on the freeway for my 15 mile ride to work. Today I noticed speed limiting  while riding at 55 degrees. The first year I had the bike it didn't seem to be noticeably affected by outside temperatures until they dropped into the low 40's. As soon as I got home from my ride this evening I checked the temp on the battery and controller through the app on my phone. Temp of battery was 93 degrees. Temp of controller was 103 degrees. Temp on motor was 155 degrees Fahrenheit.   Any ideas as to the cause of the limiting at relatively high cool temperatures?  I know at some point with the outside temperatures cold enough,  the battery will be limited as to the amount of current it can deliver due to rising internal resistance at cold temperatures. But the fact that every passing year seems to bring a higher limiting temperature makes me think something else may be factoring in (other than just temperature)  to cause the limiting.  Corrosion between contact points?  Battery breakdown? What do you think?

[Richard230]

Have you installed any firmware updates during the past year? 

[ScootCoupe]

I would fully discharge your pack by riding around and then charge it up through an wall plug energy monitor like a kill-a-watt EZ. Then multiply how many kWh the energy monitor says it took by 0.93 because the charger that these bikes use is around 93% efficient. Then I would compare that to the nominal capacity that Zero publishes for your battery and see how the two compare.

I had a similar issue to yours with speed limiting at a reasonably high state of charger before I had my battery replaced. As these cells age and degrade, they tend to have their internal resistance increase, which leads to the batteries not being able to supply enough power to maintain higher speeds.

[SRich]

The firmware has not been updated recently if at all. I had the bike in to my local Zero dealership about a year ago but don't remember an update taking place.  I see the app (which I rarely use)  says an firmware update is available. 

I have a kill-a-watt,  so I will check the capacity of the battery to see where it is at.  The overall range I get on a charge  doesn't seem to have changed much over the time I have had the bike, but maybe that will become more noticeable in the future if there is an issue.   

Thanks for your response. 

[Shadow]

You could try a heated blanket on the ZF pack to raise the starting temperature and test your theory. Reptile warming pads and a blanket might do the trick.