Hello, From A2B!

Kyle L.

New Member
Hello! We have taken note of this great resource of a site, and wanted to lend a hand. If anyone has any questions for us we'd love a chance to answer then here for you and anyone else who may be pondering the same thing.
 

Court

Administrator
Staff member
Hi Kyle, thanks for dropping by! It's awesome to have an official voice here from A2B to address questions and such. I like the improvements you guys have made with the Octave and Alva; the key fob setup is nice and the beautiful purpose built frames continue to impress :)
 

kauaikit

Member
Hello Kyle…I've got a 2010 A2B Velociti that I purchased from an auction when Best Buys got out of the ebike business. The battery would not take a charge, so I received a sizable refund, and I then proceeded to reverse charge it above 30v so the original included 36v charger could do it's business! :)

I've now got around 1,700 cardio miles on it, but of late it's been getting weaker with a reduction in top speed. Besides 20mph bring tears to my eyes as being so slow, what is the easiest or best upgrade to get this ebike to 25mph and above?Is the 48v/800watt setup on the A2B scooter available to purchase?What is the voltage limit (46v?) for the stock controller, if the stock battery box is rebuild or an extra battery is added in parallel with the weak original battery?
 

Court

Administrator
Staff member
The battery would not take a charge, so I received a sizable refund, and I then proceeded to reverse charge it above 30v so the original included 36v charger could do it's business! :)
Hey kauaikit, I'm interested to hear how you did the "reverse charge" to fix the battery when you first bought it? Could you just do that again to restore life or was that a one time thing? This is a new idea to me, thanks!
 

Kyle L.

New Member
Sounds like you have got some pretty good use out of your Velociti kauaikit. The motor and internal controller are designed for a 36v system. I am not aware of any upgrades or modifications to get the Velociti above 20 mph. The decreased speed may be due to your battery, or even possibly the motor wearing out. I would recommend taking the bike to your local A2B dealer and having them take a quick look at it to determine the issue. If you are looking for some extra speed check out the A2B Shima http://www.wearea2b.com/us/collection/shima.

Court, my guess is that kauaikit used a power supply and connected the leads to the -/+ output ports. You can trickle charge it that way until it reached 30v, where as stated the stock charger will pick up. Is that correct? Or did you come up with a new technique? This can be very dangerous and of course this is not recommended by A2B, and we always encourage that you consult your dealer on any issues like this.
 

kauaikit

Member
Yes Kyle, that is exactly what I did….for those with a Velociti or Metro battery that refuses to charge with the original stock charger, & having a voltage below 30v, you can bypass the BMS by charging the cells from the reverse connector. This happened to me when my brand new Velociti's (2010) battery, which I purchased, sat in the warehouse for a couple of years. I did in fact tried to contact A2B service for assistance or even warranty help, but got a dead end.

You will need a cheapy 36v (Chinese) charger and a couple of small nails or paper clips. Remove the battery from rear rack. You can find the + & - with a volt meter on the "out" connector from the rear of the battery. I remember the lower left was the + & the lower right was -. You connect the charger positive and negative to the small nails inserted in each connector hole. I too connected a voltmeter, so I could watch the voltage reading. I remember allowing the charger to go to 36v before disconnecting it & then installing the battery back on to the rear of the Velociti. Then I connected the original factory charger & let it do it's business for about 4 hours.

It worked, and I've been riding this Velociti ebike the last few years without any issues…..though, I do have plans to update it's performance as a 20mph limit brings tears to my eyes.

The Shima is a great way to get around the Federal mandated 20mph limit, with throttle only! Let's see all the manufacturers have a ped assist ebike that is able to do 28+ mph.

Kyle, I've also got a collection of the older Wavecrest Laboratory Tidalforce ebikes (2005) that I ride. Originally they came with heavy front NiMH battery hubs (36v/8ah). I've upgraded the battery source to Lithium poly 46v/16ah packs & replaced the front with a 26" Shimano dyno/disc (Avid BB7) rim to power a front LED light. The performance is around 33 mph on level ground, though generally I cruise around 25mph and use the regen for most of the braking. So, I'm good for awhile, though would not hesitate for a minute to purchase the new Shima ebike if I was in the market.

Now connect me with a source to get the 800watt/48v battery that is used in the UM scooter. :))
 

JoePah

Well-Known Member
Yes Kyle, that is exactly what I did….for those with a Velociti or Metro battery that refuses to charge with the original stock charger, & having a voltage below 30v, you can bypass the BMS by charging the cells from the reverse connector. This happened to me when my brand new Velociti's (2010) battery, which I purchased, sat in the warehouse for a couple of years. I did in fact tried to contact A2B service for assistance or even warranty help, but got a dead end.

You will need a cheapy 36v (Chinese) charger and a couple of small nails or paper clips. Remove the battery from rear rack. You can find the + & - with a volt meter on the "out" connector from the rear of the battery. I remember the lower left was the + & the lower right was -. You connect the charger positive and negative to the small nails inserted in each connector hole. I too connected a voltmeter, so I could watch the voltage reading. I remember allowing the charger to go to 36v before disconnecting it & then installing the battery back on to the rear of the Velociti. Then I connected the original factory charger & let it do it's business for about 4 hours.

It worked, and I've been riding this Velociti ebike the last few years without any issues…..though, I do have plans to update it's performance as a 20mph limit brings tears to my eyes.

The Shima is a great way to get around the Federal mandated 20mph limit, with throttle only! Let's see all the manufacturers have a ped assist ebike that is able to do 28+ mph.

Kyle, I've also got a collection of the older Wavecrest Laboratory Tidalforce ebikes (2005) that I ride. Originally they came with heavy front NiMH battery hubs (36v/8ah). I've upgraded the battery source to Lithium poly 46v/16ah packs & replaced the front with a 26" Shimano dyno/disc (Avid BB7) rim to power a front LED light. The performance is around 33 mph on level ground, though generally I cruise around 25mph and use the regen for most of the braking. So, I'm good for awhile, though would not hesitate for a minute to purchase the new Shima ebike if I was in the market.

Now connect me with a source to get the 800watt/48v battery that is used in the UM scooter. :))
i've been following e bike blogs for over 5 years and that's the first time I read anything like this, and it worked!

I congratulate you on your sticktoitiveness and ingenuity!
 

kauaikit

Member
JoePah….I've noticed many of these older Velociti's listed on eBay with dead or no batteries included at reduced costs. A shame this simple solution wasn't used on many of these batteries, instead of just purchasing a new & expensive battery. No doubt many were just thrown away.

What is your A2B of choice?
 

Court

Administrator
Staff member
JoePah….I've noticed many of these older Velociti's listed on eBay with dead or no batteries included at reduced costs. A shame this simple solution wasn't used on many of these batteries, instead of just purchasing a new & expensive battery. No doubt many were just thrown away.

What is your A2B of choice?
Thanks for the tips on rescuing these batteries! Hopefully the people that were struggling to get them working at least tried to recycle them... The Lithium is still usable and very valuable.
 

lilrich1959

Member
Have used this trick on older style batteries that reached an extreme discharge and results were mixed but did revive some at least for awhile. The thing to remember is monitor the charge closely as noted above and do not exceed the nominal rated voltage before using the regular recommended charger as you are bypassing the bms there is the possibility of overcharge. Also note you cannot balance the cells from the discharge port so this is not recommended for regular charging. With all that said it sure is worth a shot considering the price and availability of replacement batteries. We occasionally get people with the cheap big box bikes like e-moto and the like coming in with this issue and they are disappointed to learn replacement batteries are more than they originally paid for the bike if available at all. It is good to offer them a chance to squeeze a bit more life out of their bikes. Unfortunately low quality bikes and inadequate education on battery maintenance instruction to the customer sours these newbies from the whole ebike experience. Customer support is vital, and too often overlooked, even the best designed product is bound to have an occasional problem how that is resolved can make all the difference.
 

Cvonstack1

New Member
Hi everyone!

I have a metro that came with the external battery dead. I was wondering how exactly did you do this reverse charging, sorry it is hard to picture from text.

My idea would be to put a nail/pin/paperclip into the bottom left and right pins on the rear port (that connects to the bike controller/motor). Then I would imagine that I would solder a wire to each pin and try to then lightly solder or find some kind of connector to get it connected to the left and right pin of the charger (not the bottom). Any incite on how to find the + and - I am familiar with electronics/multimeters but would be helpful to know how to find that out so I can double check before doing it. If you have the time I could pay for a quick phone call or 2-3 min facetime to double check everything before I hit the charge switch so it can go smoothly. One idea I had was to try this not use a multimeter (bc sounds complicated to get setup and don't yet know how to get it to work right), and let it run for 30-45 min while watching it closely and then try to charge regular way hopefully voltage gets above threshold. Any pictures would be super helpful.

Currently, when I connect the regular charger it stays green, got it to flash yellow, left over night and was flashing red in the morning. I figure it is worth a shot to try this. If this fails any recommendation how I could stuff a 36v or 42-48v cell in there. Don't need crazy mileage 5-15 miles would be perfect. Thanks for the help!
 

Coran

New Member
Just wondering if A2B are going to publish the many ways in which they can decide to void all warranty they say they give.
So far I know of two ways.
1. The bike is arbitrarily declared "clearance", despite it being boxed, brand new and unused.
2. The bike is advertised through an marketing unapproved website, eg Amazon.

Just wondering what other ways A2B can void the warranty...
 

JoePah

Well-Known Member
@Cvonstack1 His explanation seem pretty simple to reverse charge the battery. Would really like to see it work in person.

If it were me i'd get solid copper wire install it in the pin holes, and try the combination recommended, or then move the wires around until I found the + and - output from the battery. Then attach the cheap charger to reverse charge the battery and see if the voltage recovers.

I don't know for sure but if the battery voltage gets too low the BMS may prevent the charger from working.. This method bypasses the BMS.

You can buy a foot of Romex wire for cheap at home depot, then strip the insulation.


The website Endless Sphere has a lot of ideas on how to gut and replace the battery.. But those guys are more tinkerers, so beware of what you're getting into.

The ES method to bypass the BMS to charge the batteries and find the bad cells is a little more complicated.. If you can find someone who works on eBike batteries give it to them. It might be worth it.
"However, once it has drained to a "below safe voltage" (??) the BMS will prevent it being recharged as one or more cells will have dropped very low
But in order to get the pack back working again , you will have to crack it open and bypass the BMS whilst you look for the lowest cells to boost up individually to get the pack voltage back up to something like 25+ volts! when the BMS will let the charger work again.
You will need some skills, tools, a MMeter, and a lot of patience and care.
There is a site somewhere that shows how to crack that pack open ....I will try to link it for you.
EDIT:
Try this....http://grifftek.com/grifftek/Other_Fun_ ... ery_packs/ "
 

Ann M.

Well-Known Member
Folks, you don't have to open the pack to bypass the BMS to bring up battery voltage unless your intention is to remove bad cells. By doing the forced charge through the backend of the battery you can bring the voltage back up in steps and reduce the risk of a thermal overload. Our shop starts with 24V SLA test pack for a 36-48V pack and wires a high wattage bulb inline to moderate the amps to prevent overheating (Yes there are specific tools out there that will do this; however, this is really inexpensive). Generally some alligator clips with heavy duty gauge wire will clip onto the + & - posts and we keep a voltmeter plugged inline with the clips for constant monitoring. This isn't a process you just walk away from, the temp. should be monitored too for safety. Once the bulb starts to dim, then you're bringing up the voltage enough to add the next battery in the SLA pack and continue to raise the voltage until it starts to level off or the regular charger will kick in. If the initial voltage is in the single digits on a Lithium pack that has sat for a lot of months empty, the success rate of this process is not high. After finishing the forced charging process/regular charging process continue monitoring the voltage for a bit to see how quickly it drops. It's really imperative to use this battery right after the resuscitation process and cooling, putting it under load (by riding preferably! :)) and then back on a charge; repeating this process a couple of times so that the battery doesn't just collapse. If the voltage drops off fast after the forced charging or never reaches an adequately full level which will allow the bike to run, then it may be necessary to see if the problem is a few isolated bad cells or in the case of extended neglect a rebuild or replacement may be needed. We've tried the suggested method of forcing a charge by plugging in a 36V SLA charger in place of the LiIon charger (in the regular charge port) and have never had success with that technique, probably since by the time we see these batteries it may have been 6-8 months or a year or more since the last charge.

One plus, quality lithium batteries are more forgiving of neglect, so if you started with a better grade lithium pack there's a better chance of a successful restart of the battery and reasonable range. Again, please note as has been mentioned in earlier posts, this is a risky process since you are bypassing the BMS, the system that protects from thermal and voltage problems.
 

JoePah

Well-Known Member
People like options and ES has some very dedicated players who are more than just casual commenters. If someone wants to save a few $$ and get skilled on overhauled a battery pack, that's the best place to start
 

Harry L

New Member
Hello! We have taken note of this great resource of a site, and wanted to lend a hand. If anyone has any questions for us we'd love a chance to answer then here for you and anyone else who may be pondering the same thing.
Hi A2B community,
Does anyone know of a way to make my Kuo+ reach higher speeds? Do I need a new motor or controller?
 

Ann M.

Well-Known Member
@Harry L, welcome to the forum family! If you have a version produced for the US market, then without pedaling the bike is designed to go 18.7 mph which allows you to have a pretty decent range on that newer 36V 9ah battery. Please share where you live, since this may be why your ebike is a bit slower and there may be options, like a different controller to help you to cruise a the local speeds that are legal in that area.
 

Harry L

New Member
@Harry L, welcome to the forum family! If you have a version produced for the US market, then without pedaling the bike is designed to go 18.7 mph which allows you to have a pretty decent range on that newer 36V 9ah battery. Please share where you live, since this may be why your ebike is a bit slower and there may be options, like a different controller to help you to cruise a the local speeds that are legal in that area.
Hi Ann, I am in the U.S. Area around nyc. Got my kuo+ through an online dealer at Amazon called appliancewarehouse. At full charge I only get about 18 mph with pedal assist. As the battery meter goes down it slows down to about 15. I wonder if I have a slower version of the bike. Is there a way to tell? Is there a way to upgrade the controller or motor? It would be great to go just a bit faster. I have my controller on 5 all the time already.
 

BullOliphant

New Member
Hey, is there anybody out there? I just bought an A2B Alva+. I have a couple hundred miles on it. Really like it so far. I love the low standover height. My wife can ride it too.

*In the owner's manual it says it can go up to 24 mph but I haven't figured out how to do that. Any ideas from other owners?