ElectricMotorcycleForum.com

Yes. They are very easy to swap. I have swapped all the body work on my 2017 SR in order to change the color from red to black.

The unofficial zero manual should have step by step but basically just remove the seat and then you will have access to all the Allen head and Phillips head screws you need to remove in order to swap tank.

Sent from my Pixel 3 using Tapatalk

I think the reason is because Zero is still using the same battery architecture as in other models but in a new case which allows better heat dissipation. If that's true then they suffer from the same issue of the pack voltage being too low for all but a few DCFC that actually follow the full spec.

In addition 12kW onboard charging is cool but almost no public chargers support that.  And it's unlikely that many public 12kW stations will get built since the direction of infrastructure is DCFC over high power AC.... rightfully so.

Wrong decision in my book. Without DCFC it's hard to justify the SR/F premium over the SR unless you are going to a track.

Sent from my Pixel 3 using Tapatalk

Not yet but I have two bricked batteries in my garage that I plan to tear down.....at some point.

If you are going to tear down I would do it soon. 2013 batteries used a potting that corrodes the cell membrane and can result in a fire. They were recalled.....at least I'm pretty sure it was MY2013....I'm sure others can confirm.

I would put your second brick outside with the one that won't take a charge.

Even though it's out of warranty you may be able to get replacements from Zero due to the recall....of course you should try that before you tear down.

Sent from my SM-G950U using Tapatalk

I will further explain cell balancing as follows and hopefully this will clear up what I described earlier...

There are TWO types of cell balancing.  For the sake of discussion I will call them (1) Passive Cell Balancing, and (2) Active Cell Balancing.

Passive Cell Balancing = Cell balancing that takes place naturally as I described previously.  This type of cell balancing is completely foreign to most self proclaimed "experts" on lithium batteries since their experience comes from the hobby world (i.e. radio controlled cars, trucks, planes, drones etc.).  The cells used by the hobby world are generally of a much lower quality than what is used in our bikes.  The cells in our bikes have a VERY tight spec tolerance on both capacity and internal resistance.  This is done by screening the cells and only using those that meet these very tight specs.  It is because of these very tight tolerances that this passive cell balancing actually works.  You can NOT rely on passive cell balancing for cells that are not matched (i.e. capacity and internal resistance).

Active Cell Balancing = Cell balancing that requires the BMS to actively manage the balancing of the cells while the charger is in CV mode and current is below 4 amps in order to get the balance to within a very tight margin (less than 5mV as I stated previously).  Doug and others are correct that this only takes place at the very end of the CV charge cycle.  As I stated previously, on our bikes it takes place when the current to the pack is less than 4 amps.  When most people talk about cell balancing this is what they are talking about.  For the charger, all that is required is for the CV voltage to be correctly set such that current is low enough when the pack nears 100% SOC.  If the CV voltage is set too high then the charger current will be too high when pack voltage reaches 100% SOC and the BMS will cut off charging without any active cell balancing.  If the CV voltage is set too low then active cell balancing never takes place because pack voltage doesn't get high enough to trigger the BMS to start active cell balancing.

I'm certain that Terry and Brandon are very familiar with both passive and active cell balancing and they also know that active cell balancing only takes place at the end of the charge cycle.  I feel confident in saying that when they said " don't have to worry about cell balancing not occurring until 100% SOC." what they meant is that due to passive cell balancing the cells will be within "acceptable" balance without charging all the way to 100% and allowing active cell balancing to take place and not that active cell balancing starts at 50% SOC.

mrwilsn is right at every points.  Thanks btw for explaining that so well.

Doc

Thanks Doc, it's my pleasure.

The bikes 'cell balancing' function doesn't take place until the very end of the charge cycle when current going to the battery pack is less than 4 amps.  The Zero App will not show current when it goes below 4 amps so the only way to know that it is happening is if you either use a watt meter on the outlet the bike is plugged into or if you have a DVM connected to the battery (like I do) and can see that the contactor is still closed even though the app doesn't show the bike is charging.

As the battery discharges the cells slowly get out of balance as a function of the internal resistance of each individual cell.  Cells with the highest internal resistance will discharge slower and cells with the lowest internal resistance will discharge faster.  Cell imbalance will be the highest the lower the pack voltage gets.

Even if your pack is at 0% SOC this process reverses naturally the second you start charging the battery pack.  The cells with the lowest internal resistance will charge faster and the cells with the highest internal resistance will charge slower.  Since voltage of the cells with the highest internal resistance would be slightly higher at low SOC than the cells with the highest internal resistance the effect is that cell balance naturally starts to get smaller.  This doesn't require any special function of the charger it just happens as a result of chemistry.

The cells Zero uses are so well matched that cell balance will typically be very low (less than 5 or 10mV) before the actual 'cell balancing' function takes place.

Anyone can test this just by using the Zero app.  Ride your bike down to low SOC and use the app to check cell balance.  At low SOC the pack cell balance can be anywhere from 50mV to 100mV or more.  Connect your bike to the charger and within minutes you will see the cell balance start to drop.  Check on the bike every hour and you will see that every time you check the cell balance will be smaller and smaller.  By the time you get to 100% you should be less than 10mV (I frequently see 1-2mV cell balance on my bike).

In reality, it's not the charger that facilitates cell balancing the cells to be closer than what would happen naturally.  The charger has two modes.  Constant Current (CC) and Constant Voltage (CV).  The value at which the charger goes into CV can be adjusted by the manufacturer.  Once the battery pack is at 100% SOC the BMS actually facilitates cell balancing.  The charge is still coming from the charger but the BMS allows individual cells to be balanced using the balance wires and bleed resistors.  Thus it would be possible to balance the cells to the 1-2mV range at any SOC by using programming.

Tesla's for example allow you to set your max SOC value.  If, for example, you set the max charge to 60% the charger will go into CV mode once the voltage rise value hits the 60% SOC value.  As the 'resting' pack voltage hits the 60% SOC the cells can then be balanced at that voltage.  Unfortunately, Zero does not support setting a max charge and will always attempt to charge to 100%.  Changing this for a Zero would require new programming for the charger (to go into CV at a lower voltage) and the BMS (to facilitate balancing).

Whatever caused that definitely didn't come from inside the battery.

Something got on your battery.... wipe it off and enjoy the ride....your bike is fine.

Sent from my SM-G950U using Tapatalk

I think 2017 was a rough year for all motorcycle sales but Zero was hit especially hard....most likely due to the uncertainty around the federal tax credit in the USA.  A dealer I talked to had sold 10 bikes in 2016 but only sold 1 bike (not counting demo bikes) in 2017.

On top of that, it is my understanding that for 2018 Zero changed the bank they require dealers to work with to floor demo bikes.  I have been told the change in requirements are a real pain in the butt and makes it harder for small dealers to get financed to floor the demo bikes.

I think these two factors have resulted in a high number of dealers dropping for 2018 model year.  I think dealer support is a legitimate concern for any new buyer so I hope Zero gets things figured out for 2019 bikes.

The app only shows voltage when kick stand is down and/or kill switch off.  While riding the app switches to riding screen which does not have voltage as an option.

A workaround while riding is to flip kill switch to off so app changes to battery page so voltage can be checked, then flip kill switch back to run. This isn't perfect as sometimes the app misbehaves in one way or another.

Electric Cowboys mod shows voltage on the bikes display by just rolling to neutral throttle while riding. No messing with phone before ride.  Doesn't require flipping switches back and forth. Doesn't matter if kick stand is up or down. Works while riding or charging.

Sent from my SM-G950U using Tapatalk