Rize Liberty – What a mess for a $15.00 design oversight.

alfgar

100 mW
Joined
Mar 18, 2017
Messages
41
*** PICS AT THE END ***

Picked up a 2020 Rize liberty bike a month ago from one of our local “for sale” sites. It was advertized with a damaged motor harness.

Turns out the damage was much more extensive and all, in my opinion, could have been avoided with a $10-$15 Torque arm.

I have little experience with eBikes but some with manufacturing systems with large HP electric motors. And this is where I learned the importance of a torque arm.

This hub motor is 48V with 1000W. And all this torque is suppose to be kept at bay with a 3/8” thick aluminum drop out and a short “lip” torque washer.

The aluminum drop out’s did not have a chance. The steel shaft ripped right through, even snapped one of the drop outs.

At that point, the hub motor shaft spins and tears the harness.

Rize does not sell motor harness but was very quick to offer to sell me a new motor for $450+ tx and shipping. At this point I didn’t bother to ask how much a new swing arm (with new drop outs) would cost.

At least a $1000.00 in damages on a 2 year old $2500+ bike because of a missing $10-$15.00 torque arm.

Couldn’t find the ¼” OD diameter OEM motor harness so I got a larger OD harness extension and “macgyvered” it to the hub motor.

At this point I needed to address the rounded drop outs. So I 3d printed some samples that seem to look good and had a local shop cut them out of ¼ stainless. One for each side taking care of the torque arm issue this time around. ½” thick total of stainless should avoid any shaft spins.

Everything came together nicely….mechanically that is. Electrically it’s now giving me issues I don’t even not know where to begin.

When I throttle, after a short while, all power shuts off completely. I can turn it on again but it always shuts down after a short while. I thought it might be the throttle so I disconnected it and tried only the PAS system. The bike shuts down in the same way.

Any suggestions on where to look or what to do would be appreciated. *** Keep in mind I’m a simple minded handyman with no special tools other than a Volt meter.

Voltmeter shows 53.4 volts after a full 24 hour charge.

Thank you in advance to everyone.
 

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Nice work!

What is that old saying “For want of a nail, the shoe was lost. For want of a shoe, the horse was lost. For want of a horse, the rider was lost. For want of a rider, the battle was lost."

So yea, a torque arm could have saved the whole mess from happening.

But it looks like you have the mechanical stuff back together.... so, the electrical part.

My first notion is that your battery has a weak cell or cell group that looks like it is charged but hits low voltage cutoff shortly after use. Since you only have a DMM, the way to check for a weak group is to open up your battery enough to test the cell groups.

A "Mr. Obvious" test:

However, before we go to the battery make sure all your connections are in good shape and snug. Examine all your connectors for loose wires or connections. Also, make sure your brake levers are well adjusted so the brake cutoff switch (in the brake levers, if you have them) are not activating.

Once you have done the "Mr. Obvious" test of examining all connections and wires, I will ask a question:

Question: Is it possible to open up your battery to see all the wires? The reason for this is to find out if we can test your cells via the balance wires from the BMS.

So, do the "Mr. Obvious" test and then tell us about your battery. Is it easily opened?

Also, if you do not have any display or meter on that bike, you can get a rc watt meter fairly expensively and wire that inline with the battery and watch it to see what your battery is doing while riding ie, amp and voltage usage.

If you don't mind spending the money, you could get a cycle analyst which is very useful for all kinds of stuff.

Oh, and BTW, I have no affiliation to the manufacture/seller of this product. I suggest it because it is useful.

https://ebikes.ca/product-info/grin-products/cycle-analyst-3.html

[youtube]5ME7s3Y2BUQ[/youtube]

So when you are done with the above, let us know how it goes.

:D :bolt:
 
I think your old saying hits the “nail” right on the head , pardon the pun :D .

In my experience this is called a single point critical failure and is usually avoided like a plague in all designs? Would we design electrical systems without fuses?

Not sure if Rize realizes what kind of a hit a simple consumers takes when a $2500+ expense goes to the crapper just 2 years later.

Thanks for all the advise, hopefully life will allow me some fun over the coming weekend(s) to try some of your suggestions.

The battery I have seems to be an “reention dorado 48v battery”. And there are a number of YouTube videos showing how to open and diagnose - seems straight forward enough. Just contacted the seller and he told me that the battery was nearing its end with only 20-25 km per charge.

There’s even a video on resetting the BMS though I’m not sure why and for what a reset is needed. I will probably try that as well.

And I will begin with Mr Obvious .

Thanks again
 
If the bms in your battery is easily accessible, post a picture of the sense wiring so we can see if there is something else you might need to know.

:D :bolt:
 
Opened up the battery easy enough, 4 screws.

Tried the reset thing by disconnect the harness but not much changed. Actually no…..

This time the power still cuts off but the display remains on. So the system still has power but the throttle and PAS has no affect until I shut it off and on again. Before power and display shut off.

Low power demands seems to be ok but cranking up the throttle or pedals definitely shuts things down.

Pictures of the battery are below. One of the pics has a yellow arrow showing one of the tiny LED’s flashing orange-red. Don’t know if that’s normal.

Didn't pull the fuse completely out but it looked good.

Time permitting I will try to check all the bike connection for loose fittings.
 

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I don't know why the led is flashing. Perhaps the bms is sensing a fault, but that is only a guess.

If you would, give us a picture of the row of connections in the image below. Try to get as many wires out of the way so we can see it clearly. These are the leads you will need to test after a full charge and then again after the bike stops running.
There is a specific order to test them but I need a clear picture to give you a few pointers on what the order is.

Also, check the white connector that goes to those connectors. If you can disconnect it then give us a picture of where the wires connect to the pins.

Row of connectors.JPG

:D :bolt:
 
Regarding the damaged axle: Keep in mind that non-turn washers and torque arms are only one line of defense against motor reaction torque. Adequately tight axle nuts are pretty much equally important. Those are not the responsibility of the manufacturer, but rather that of the end user.

I've seen more spun axles on bikes equipped with torque arms than on bikes without them.
 
Wow, thanks for all the input everyone, really appreciate it. I will get to the pics requested in due time. Unfortunately life is getting in the way of FUN right now. Older parents to take care of and stuff.

As to the term “MacGyver-ing”, I was just dating myself for lack of a better word.

Guess I was not clear in my original post. Only reason I had to improvise with the harness is I could NOT find the OEM part. Wrote to Bafang (many times) and multiple suppliers, aftermarket parts sites along with the suggested suppliers on this site.

NO ONE had a 6mm (.250”) OD wire harness. Everyone had the 8.8mm OD wire hardness. I cannot fit a 3/8” diameter wire inside a ¼” hole.

So I removed the outside insulation on the 3/8” diameter I bought….cut out the three 12-14ga wires and soldered them with the original harness 16-18 ga wires I cannibalized. I basically used the OEM wires and then heat shrunk the whole thing, and installed it to the motor.

I don’t doubt someone now will whip out a harness supplier….but I couldn’t find one then.

As to torque arms being the end all to all saviours, I agreed and I didn’t mean to give that impression.

What I was trying to say is that for this bike, the bolted nuts became a SINGLE POINT failure. After much vibrations and use, for sure those nuts can come loose.

In any decent or good engineering design, you must have safety redundant system protecting the rider and the equipment. First strange thing is that there are no lock washer, there are only thick flat washer.

And the cherry on top as to negligent IMO, the lack of the $15 torque arm. How the heck will aluminum drop out hold all that power if the nuts come loose.

As I noted above originally, how many $2500.00+ electrical systems out there do not have an inexpensive fuse / redundant systems?

Around here the majority of e-bikers are simple users with many of them elderly. They barely remember or know to fill the tires with air. Something needs to "hold" potential disasters until they go for their checkups.

If a nut(s) comes loose there must be a safety that will not scrap a $2500 bike or worse seriously hurt the rider.

Sorry, didn’t mean to rant. But in my manufacturing world, this would be a recall and warranty repair.................................OK moving on now, back to fun :D :D :D
 
Thanks again for the detailed guidance. It is definitely a good reference for me. I have a little experience with ebikes as I have done it once before. As they say, I know enough to be dangerous.

My issue here was the symptom of shutting down. I have no experience on what this could be.....Battery, Controller or even the harness repair itself. I just have no idea where to begin based on the shutting down.

I like fixing things and challenging myself to new stuff so a few years ago I bought an A2B with a dead battery because of years of storage without charging. So batteries I’ve touched before.... once that is

Ended up bypassing the BMS and charging / balancing the cells individually to a high enough voltage so the BMS would take over and charge the battery properly when plugged normally.

When bypassing the BMS, I learned ( on this site) to use some light bulbs in the circuit to keep the amps low enough to not overheat & blow the cells, or catch fire.

As to getting the most out of battery life, I agree most people don’t research enough. I’m going on my 12th year with my wireless lawnmower and I use the same precautions on anything that uses chargeable batteries. These things are WAY over priced.


** As to this bike battery, I remember measuring the voltage around 53.4 when fully charged and around 52.6 volts about 20 minutes later after trying it out with 3 or 4 shut downs and restarts.

No voltage on my display unfortunately. Just percentage and that is always steady.

When I throttle or pedal VERY slowly it seems to go without problems. When I “floor it” (throttle or pedals), it shuts down in a few seconds.

I will post some pictures again of the BMS and wire harness colours as soon as I get a chance to open the top again. If I can measure some voltages on the harness without pulling the pack out, that would save me some time.
 
alfgar said:
...When I throttle or pedal VERY slowly it seems to go without problems. When I “floor it” (throttle or pedals), it shuts down in a few seconds....

That is defiantly an indication that sagging might be causing a low voltage cutoff by your BMS. Post the pictures I requested so I can make some pointers. I bet you have a bad cell group.

:D :bolt:
 
I believe 53.4 - 53.6 Volt is as high as it's gone with an overnight charge. I can try leaving the charger for longer if that would help? I didn't think that one volt short of 54.6 meant a big deal for a 2-3 year old battery.

Regardless, below is the pic asked for. Well i believe this is what is being asked. If I can measure across the harness pins I can at least confirm a battery issue before I take things apart.

If confirmed, then it's a question of if I want to tackle switching out cells. What tools are needed, components, etc. Don't have spot welder, can it be soldered, is it value added to do it my self and so on.

Boy do I realize these batteries are expensive but I don't believe I will be repairing many so I don't need to invest a large amount of $$$ on tooling.
 

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It might not be a problem, but that plug is not fully seated into the socket at one end. If the pins in the socket or the contacts in the plug are not long enough, they won't mate fully at one end, and the BMS won't be able to correctly read the cells, which can cause various problems depending on the specific BMS design, including imbalanced cells (some overcharged, some not fully charged, etc).

This can be tested by measuring with the voltmeter on DCVolts. Turn the BMS over so you can access the solder pads where that socket is mounted to the BMS. Black meter lead to the first pad at one end of the plug. Red meter lead to the next pad over. If the voltage is positive, you're starting at the most negative end, if negative you're at the postive end. Works either way, just make sure every measurement you make shows the *same* polarity. (any that don't are very bad, meaning reversed cells that may be a fire hazard).

Note that reading down, including polarity. Move black meter lead to pad red lead is on, and move red lead to next pad over. Note reading down, including polarity. Repeat for the rest of the solder pads on the BMS board for that plug.

The reason for measuring at the pads is that this ensures you are seeing what the BMS sees, so any connection failures will also show up too.


It's just as likely that there are degraded cells with unequal capacity/capabilities, that are not charging equally to the others, causing the problem. This can be tested (eliminating connection failures at the BMS plug) by measuring the above at the metal showing in the plug pins at the back where the wires come out, if it's visible, or anywhere you can access the metal contacts in the plug.

If you have access to the points on the cells where the balance wires connect to them, you can do this measurement eliminating all connection issues to the BMS (it doesn't eliminate cell interconnect issues).


Any cells that are different in voltage between the two measurement points (BMS and plug or cells), indicate a connection problem between cells and BMS.

Any cells that are different in voltage between each other in both (or just the cell test) mean the ones will less voltage have less capacity / capability, and mean the whole pack is limited by the worst of those cells.

If you can test during charging (from a low state of charge, nearly discharged is best so more current flows) then the cells with the worst problems will show up with the greatest voltage difference.

Same for testing during discharging, but harder to do without a sufficient test load of some kind, as testing while riding is difficult. ;) Various bike/battery repair threads discuss test loads, including old toaster ovens or other heating-element devices.



If you look up the cell specs for your specific cells, there may be a discharge curve for them that shows what voltage drop they should be for a specific point in their capacity (state of charge, SoC) and current flow.

At the lowest current flow they show (or static if they have one, for static voltage tests), the difference between the actual voltage and that of the chart shows you the difference in the amount of capacity that cell has. (to see difference in capability, it has to be a test under load similar to or at actual loading).

If the ~1v difference you see between full charge now and original full charge is spread across the pack, it's not a big deal. But if it's in one cell group, that's a fairly huge difference in cell capacity between that one and the rest of the pack, and means the pack is much more limited than if it were spread across them all.



If the BMS has a balancing function (they don't all) then leaving the pack on the charger (while watching it; I don't recommend ever leaving one unattended due to fire risk) will slowly correct many imbalances. A badly imbalanced pack may take days or even weeks to fully rebalance, but it does not fix the problem causing it (that requires cell replacement, and is often better fixed by replacing the whole pack with a new one).


I don't recommend soldering to the cells, but if you know what group is "bad" and replace that whole group with a new one already spotwelded together, you could cut just the welds on the interconnects from the cells in the old group, leaving all the interconnects intact, and then solder those interconnects to your new group's interconnects, which will pass a lot less heat into the cells (causing less potential damage to them). You just have to be careful not to heat the insulators between the cell edges and the interconnects (assuming cylindrical cells and spotwelded metal strips as interconnects). f

There's a lot of battery build / repair threads that show various methods and tools you can use, and numerous "which soldering iron / station" threads to help with that choice.



Regarding the manufacturing cost-reduction choices made, they're unfortunately not all that uncommon in ebikes and varous ebike parts / kits / etc. (and numerous other non-bike-related devices of all kinds), and certainly cause enough grief to end users; the companies can just blow them off and not honor warranties even if they offer one (companies based outside the country of sale have an easier time of this, but if the end user doesn't have the means to pursue it it can happen regardless).
 
The harness not seated well was me. I was trying the BMS reset thing I read about. I had just placed it lightly back for the picture. It’s snap in good now.

Not sure if I understood the direction properly but this is what I got. (Polarity was the same all the way through.

Starting from the left side of the picture with the black meter lead on the black harness “solder pad” and the red meter lead on the green harness “solder pad”.

Black & Green = 4.0 V
Green & yellow = 4.0 V
Yellow & Red = 4.0 V
Red & Black = 4.0 V
Black & Green = 3.4 V
Green & yellow = 4.0 V
Yellow & Red = 4.0 V
Red & Black = 4.0 V
Black & Green = 4.0 V
Green & yellow = 4.0 V
Yellow & Red = 4.0 V
Red & Black = 4.0 V
Black and red = 4.0 V
Extreme left side Black & Extreme right side Red = 52.6 V

I guess next step is to put some time aside to open the pack and measure the cells directly.

Having a hard grasping that such a small 0.6V delta from one to another is bad vs. Good.

Havent given much thought yet as to testing during discharging and other suggestions but I will.

Thanks.
 
alfgar said:
Black & Green = 4.0 V
Green & yellow = 4.0 V
Yellow & Red = 4.0 V
Red & Black = 4.0 V
Black & Green = 3.4 V
Green & yellow = 4.0 V
Yellow & Red = 4.0 V
Red & Black = 4.0 V
Black & Green = 4.0 V
Green & yellow = 4.0 V
Yellow & Red = 4.0 V
Red & Black = 4.0 V
Black and red = 4.0 V
<snip>
Having a hard grasping that such a small 0.6V delta from one to another is bad vs. Good.
It depends on the cells in there, and what is actually causing the issue.

BTW, since you're reading good equal voltages on all but that 5th group out of 13, it's likely that it's not a connection issue (still worth checking at the cell groups if it's not problematic to do so, just to be certain).

To give some idea of what the difference means, here's a "random" cell characteristic page
https://lygte-info.dk/review/batteries2012/Molicel%20INR18650-P28A%202800mAh%20%28Gray%29%20UK.html
and their discharge curve:
Molicel%20INR18650-P28A%202800mAh%20(Gray)-Capacity[1].png
It doesn't list a static voltage vs capacity, so we'll use the the lowest current (0.2C, or 0.2 x 2.8Ah = 560mA).

To read the chart, find the voltage on the left, and follow it's horizontal line to where it intersects the top line (in this case) of the curve, and then go down to the capacity listed along the bottom. (if testing under higher load conditions, you'd use the appropriate curve. Note that current is divided by the number of parallel cells, so if it's a 4p pack and you draw 10A, that's the 2.5A curve you'd follow, since all the curves are for just one cell under test).

For these, a 4.0v SoC means 0.5Ah less than full, out of 2.8Ah. (different cells will have different characteristics in this kind of curve, so knowing what your cells are)

A 3.4v SoC means 2.25Ah less than full, out of 2.8Ah.

So a cell at 4V is relatively close to full, and a 3.4v cell is nearly empty.

That's why the pack is cutting out under load, and likely doesn't run long even with little or no load, because the group at such a low voltage has almost nothing to contribute to the output.
 
Sure seems like a bad cell group. Although, there is an outside chance that the offending 3.6v cell group is simply out of balance with the rest of the cells.

Ways to balance that cell group:

You could, in a safe place leave the battery on the charger for 7 days to let it get up to balance with the other cells. (Checking periodically to make sure nothing is getting to hot.) If that cell group is weak then upon riding again it will show a similar result to what it is doing now. However if it is simply out of balance, then that group will perform similar to the other cell groups.

You may not need 7 days, and could check that cell group once a day or so to see if it is at the same voltage as the rest of the cell groups.

Or you could pull the white connector from the BMS and insert two small wires into the proper pin holes and apply a very low amperage 4.0v until that group is at 4.0v. Then put it on an overnight charge to fully charge and balance the pack and then go for a ride and see what happens.

:D :bolt:
 
e-beach said:
Sure seems like a bad cell group. Although, there is an outside chance that the offending 3.6v cell group is simply out of balance with the rest of the cells.
To get out of balance (presuming originally identical SoC for all cells and all groups), any cell group has to have different characteristics than the rest of them, which makes it "bad" in that it cannot supply the same amount of current or capacity that the rest do (it might be more, or less, but not the same, so it will always become unbalanced by some amount during charge and discharge, and have to be rebalanced (manually or by the BMS).

`
The difference could be a single cell in the group being different, or damaged, etc., or an interconnect failure so not all the cells in the group contribute equally (or at all), or an entire group of cells being different than the rest of the groups, etc.


So "bad" in the context of the above means it causes a problem with the pack charging and discharging as designed for it's entire SoC range (will cause early shutoff of one or the other or both).

In practice it usually means an actual failing/failed cell or group, or one that is different from the rest due to different brand/model/batch/etc.
 
amberwolf said:
.....In practice it usually means an actual failing/failed cell or group, or one that is different from the rest due to different brand/model/batch/etc.

But what of the BMS? Could that also be the problem?

:D :bolt:
 
Boy you guys are way ahead me on diagnostics, cause vs. symptoms but I believe I get the gist of it. Well at least I hope I do.

Was opting for charging just the group of 3.6V but the point of why that group is at 3.6V to begin with and will likely degrade again , somehow makes sense to me. SO I think it might be best to open up the pack and measure each cell directly.

*** My personal choice needs to be what is value added going forward.

I doubt I will repair many of these going forward. So do I spend $500-$700 instead for a new battery or do I invest in tooling like: spot welder, nickel strip, cells, and whatever else I don’t even know I need. And what is the likelihood of more cells dropping next month / year ?

Where I can use more of your help is on these chargeable mini battery spot welders I’ve come across. They go from $70 to $100 Canadian….and up obviously. This might make it worth my while. If they are any good that is.

[youtube]https://www.youtube.com/watch?v=TI_ZV-5WHi4[/youtube]

I have lots of chargeable “stuff” in my life so a small investment such as this could pay for itself for years to come if I can use the same approach on all batteries.

I assume I can repair wireless drills, garden tools, laptop batteries , and countless other stuff.
 
The simple test is to give you battery an overnight charge and test the cells again. The next simple test is to do as I suggested earlier and let it charge for a longer period to see if the offending cell group starts to move into balance.

It probably won't but it is a free test that doesn't cost money and you don't have to take anything apart any further while taking in your next best course of action.

The problem with adding a new cell or cell group with older cells is that the new cell will have to cover for the loss of capacity of the older cells causing it to stress and heat up. It might not be a problem, but it might also get hot enough to cause a fire. It is best not to mix old and new cells.

As for metering individual cells, that is not possible if they are tab welded into a cell group. You would have to remove one of the tabs from the cell to isolate it for metering. 13 cells in a group ="s 13 torn tabs.

You have already identified the cell group with a weakness. You can, if you want trace those wires to find out which it is.

:D :bolt:
 
e-beach said:
amberwolf said:
.....In practice it usually means an actual failing/failed cell or group, or one that is different from the rest due to different brand/model/batch/etc.

But what of the BMS? Could that also be the problem?

:D :bolt:

If it has a resistive balancing function with a stuck on shunt on that group, it could be continuously draining it down, sure.

But that's much less common than failed cells or different ones, based on repair threads around ES, hence the "usually" in my original statement. ;)
 
In for a penny, in for a pound I guess. Opened it up. It was easy enough to slide out.

Harness pins are way too small to charge 4.0V with anything I have in house. So I will see if I can charge it on the pack somewhere by chasing the wires.

Guess I'll take the winter to slowly see if I can repair it. Need to continue to research though. I only have about 5 minutes experience in this field but I have seen a few different types of cells...... but never these before.
 

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alfgar said:
I only have about 5 minutes experience in this field but I have seen a few different types of cells...... but never these before.

They look like either 18650 or 26650 cells (probably the latter; you can easily check which as they'll be either 18mm wide x 65mm long or 26mm x 65mm). The wrapping color reminds me of Molicel, but that doesnt' mean much.

There is probably a p/n on the hidden area under the cell holders, most likely just before the "E26".

I unsuccessfully googled around for that number, as it's not uncommon for cell designations to be something like 18650-X12 or similar, and may also have a designation prefix such as ABC. A brand name will be on the "good ones" as well; generics often leave that off.


The rest of the number that's visible in the middle is likely a batch code.
 
Thanks ebuilder, appreciate the suggestion and probably would have went that route 30 years ago…heck even 10. Would have loved one of these back then to push the limits a little and have enough power left over to bring me back.

I’ve always enjoyed new projects , challenges and lost causes. With the damage it had, this thing was destine for the scrap so I just want to make sure it did end up there.

Thought I would have been done by now TBH, I knew about the motor harness and then found out about the swing arm drop out damage. And now the battery. At this point it’s a tad bit a question of pride to get this running.

Yes I realize a new battery will solve the issue and my research shows, as you noted, I can fit some pretty nice batteries on the bike. I may end up going that way in the end. Just hate the idea of giving all that money to the battery cartel.

I guess I'll spend some time looking at the battery topics on this forum...should fine some nice ideas / suggestions.

This is the bike. (Missing the newly recovered seat)
 

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I will likely go the way of buying a battery but I need to make absolutely sure my shutdown issue is the battery. I'm still not sure it is not something else at this point.

As I'm typing, I have a 5V charger (with a 100W light bulb) charging the 3.4V cell pack. I want to bring it up to 4.0 V like the rest and see if I can go for a few km's with it shutting down. If it doesn't shut down, I can be confident it's only the battery and look at investing on a new one.

Question as to charging the 3.4V cell pack. Do I bring it to 4.2 or 4.0 before I put the entire battery pack on its charger overnight?

thanks.
 
Managed to bring up the lower cell pack to 4.0 V . Reconnected the BMS harness and charged the battery for 24 hrs.

First row of figures is freshly off the charger. The second row was after a 12.1 km ride. Mainly pedal assist.

Black & Green = 4.16 V = 3.84 V
Green & yellow = 4.15 V = 3.84 V
Yellow & Red = 4.15 V = 3.85 V
Red & Black = 4.15 V = 3.84 V
Black & Green = 4.13 V = 3.85 V
Green & yellow = 4.15 V = 3.84 V
Yellow & Red = 4.15 V = 3.84 V
Red & Black = 4.16 V = 3.85 V
Black & Green = 4.16 V = 3.85 V
Green & yellow = 4.16 V = 3.87 V
Yellow & Red = 4.15 V = 3.85 V
Red & Black = 4.16 V = 3.84 V
Black and red = 4.14 V = 3.82 V

The bike panel was showing 82% battery when I rode it in the garage, 10 minutes later it went up to 89% ???

Tough the power did still shut off a number of times I got much much more ride this time out of it. In the past it would shut down seconds after throttling. BTW this bike brought me to 39.9 kmh with headwinds. Didn't know it could do that.

This might mean something to those of you with more experienced but it shut down more times on the throttle then the PAS system.

Off the charger the battery read 53.9V , after the 12km ride it was at 49.6.

Kinda confident at this point that the shutting down is related to the battery. Only thing left is to decide if I want to spend another $700-$1000 on a new battery for this bike.

As an FYI: the batteries measure 18mm by 65 mm. Guess that makes them 18650's

Thanks everyone for your help. I’ve picked up a few new things.

P.S. Ride safely everyone, as I've hit the ground coming off motor bikes in my day......... it is definitely not fun.
 
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