Golden Motor Build 48v and Beyond!

[icecube57]

In my last post i said I had tire issues.I had a busted tube and the side wall of one of my tires blew out. I scraped some money and bought some bell wally world kevlar reinforced tires. Im not proud of my purchase but then again i like instant gratification. I gained 3-5 mph on the flats and downhills. Its a slick with slightly agressive tread for city/urban use. They roll very quiet compared to the knobbies I pulled off that sounded like a 4x4 truck going 70 mph with mud boggin tires on. I clocked 33 on the flats and 37 on my down hill. Keep in mind my free wheel speed is 44mph right off the charger. Cant wait until I get my torque arms cause i need some regen braking bad... Im thrilled at the speed increase. Ill post a wheel POV video.... You can hear my motor purr whine and growl as it hauls my fat arse around the park.There is still some wind but its alot better than my other vids. I had every intention of draining my pack today to do a review on my ebay duct tape battery pack. That thing is freaking huge. I spend over 30 minutes doing hard riding and only manage to drain 11AH. It was to cold to continue. I like the flat discharge curve and even performance even tho there is obvious 2-3v voltage drop with the load. Its pretty flat. I feel spoiled compared to my old SLA setup. Im expecting there to be 17-18AH in the pack due to the perkuets but i gotta get to the bottom of the bucket to let you know first... one day guys... one day.

[dogman]

I have 2000 miles on one of those wally world bell tires, and it still has a ton of tread left. Lots of sharp rocks, metal stuff etc, and it is fine.

[docnjoj]

Ditto on the Walmart tires. I need at least 2 at a time (front toe in sucks but is better than toe-out or zero) and they are lasting much better than my Big Apples did, plus they have less grip! That means a slide instead of a flip! Definitely better IMHO!
otherDoc

[icecube57]

After reading the recent NDE story I bought some torque arms from Earl at the Powerridestore. They torque arm needed some work but i got it on and i fit it inside the fork. I also got some Andersons but not enough to finish all my connections. I bought two headlights. I plant to buy a DC to DC convertor and tap power from my battery to power the headlights but right now im using ( 4)2600mah AA NIMH batteries in each headlight. I plant to recharge once a week and carry some regular alkaline in my emergency backpack just incase im stranded somewhere. Bought a wider comfort seat. That narrow assed stock seat was doing a number on my chode. I couldnt walk right or sit for atleast 3-4 days after that 30 mile test run. I also raised my handle bars about 1 1/2 inches... Ride feels much better.

[icecube57]

Today I did a dusk/night ride. I did manage to drain my pack today. I got about 16AH out of a 48v 20AH pack. I did WOT throttle 80% of the time. I pedaled during the start up until I couldnt match the motor speed and let rode the throttle rest of the time. I got about 23 m. The motor was mildly warm. The bms on the battery cut me off.I could technically keep pulling out of the pack at 5-10A but i couldnt stay in the butter zone. Someone please tell me is the 16AH I got out of my pack reasonable or do i need to do some sniffing to find the dead rat. I was drawing 30A most of the time. I wasnt babying the throttle. My light worked but they were lack luster. Im going to find a supplementary LED light system on EBAY I like they way the projected. For them to be so cheap i like that pure white blinding light. They had a wide angle mid throw even light beam The two I have a focused far throwing beam like a flash light. I also had a failed anderson. Bad crimp. I fixed it with my kit bag in the middle of my ride. Thats all i got for now.

[Russell]

Today I did a dusk/night ride. I did manage to drain my pack today. I got about 16AH out of a 48v 20AH pack. I did WOT throttle 80% of the time. I pedaled during the start up until I couldnt match the motor speed and let rode the throttle rest of the time. I got about 23 m. The motor was mildly warm. The bms on the battery cut me off.I could technically keep pulling out of the pack at 5-10A but i couldnt stay in the butter zone. Someone please tell me is the 16AH I got out of my pack reasonable or do i need to do some sniffing to find the dead rat. I was drawing 30A most of the time. I wasnt babying the throttle. My light worked but they were lack luster. Im going to find a supplementary LED light system on EBAY I like they way the projected. For them to be so cheap i like that pure white blinding light. They had a wide angle mid throw even light beam The two I have a focused far throwing beam like a flash light. I also had a failed anderson. Bad crimp. I fixed it with my kit bag in the middle of my ride. Thats all i got for now.

Do you know for sure it was the BMS shutting down or was it the controller? If you have a regular run-of-the-mill 48V controller it likely has a LVC of 41V which will cut you off BEFORE the BMS. If you have a unit like the modified controllers sold by ebikes.ca where the LVC has been modified lower then the BMS would be the item shutting you down. Measure the pack voltage when it shuts down and if it's around 41V you have your answer.


-R

[icecube57]

It was the stock GM controller. I think I recalled it was dropping down to 42... lor lowere under load. When the BMS tripped my Watts up meter went dead also so I think it was the BMS. At that same time I also had an Anderson Connector problem so the controller might have also sensed a volt drop from that under load. I fixed it but at the same time i wrapped up my run thinking my pack was dead. This is my first deep discharge. The other 4-5 have been 50% or less.

My pack is a little unbalanced there might be a weak cell.

Here is some individual cell data from my pack. Starting from the beginning of the string to the end. I checked it through the bms connector

2.87
3.07
3.17
3.17
3.14
3.11
3.17
2.95
3.11
3.11
3.13
3.13
3.11
3.14
3.16

So I may have two possibly 3 bad sections. Or it could be a bad soldering job and to much resistance causing the variation.Maybe another charge and balance and another discharge will bring it back in line if it doesnt after a few more cycles Im going to talk to the vendor.

[icecube57]

Its just got done charging. Not balancing anymore. The data goes as followed
3.78
3.77
3.77
3.79
3.78
3.76
3.78
3.48
3.78
3.76
3.78
3.64
3.77
3.79
3.78

Seems like a bad seed or two. Maybe hiding in there.
Here is the email i sent the vendor.
2009/3/16 Christofer Parham <khristopher2000inbox@hotmail.com>

So I have been using this battery. I have done 2-3 shallow discharges using 5 AH. I also done 2 discharges to 50% consuming 9-10 AH. Today I did a deep discharge but I couldn't get past 15.5-16 AH. I was discharging at 30A on my bike. I checked the cells through the bms connector ribbon after this deep discharge run and got these values.
2.87
3.07
3.17
3.17
3.14
3.11
3.17
2.95
3.11
3.11
3.13
3.13
3.11
3.14
3.16

Seems like there might be 2-3 problematic sections. I will charge and let it balance for a while. And record the data. I will also deep discharge a few more times and record the data. Can you shed some light on what might be going. I was kind of expecting close to 17-18 AH at most out of the pack.... Im happy with the pack so far Im just seeking that missing 2-3 AH. Hope it isn't a bad cell.

Here is the response.

Hi friend
According to the data you showed me, the current discharge is not so balance. So some current is protected in the battery. The 15.5-16AH is quite normal.
If you have any problem pls feel free to contact me.

Have a good day

I kinda figured there is probably more juice in the pack but the bad cell is bring the voltage low enough to cut the bms prematurely. But 15AH is still good. But how much is really left in there. I wont know until i cycle a few more times. Its raining so today is washed out.

[dogman]

Unfortunately that seems to be pretty common with the round cell packs. Too many cells in a parallel string lets one die before the bms stops it. And some sellers may even sneak a few cells in there that are no good from day 1. Light depth of discharge would be a good idea for that pack. They do go through a break in period, but you are mostly through that now.

[icecube57]

Although there obviously may be a weak cell or two. I think the bms is cutting in way to early. I talk to a guy thats designing a bms for a123 packs and other cells and hes going to set his to 2.3v per cell. 2.2 v is when cell reversal starts. When i measured mine they were in the 2.7 which is kinda above the theoretical cut of and i could possible drain it a tad bit more if it wasnt for the bms cutting in early. I think that they factor in so much head room in designing the bms that they dont let you drain the whole pack. One to save their asses from having to live up to the warranty. Two to prevent damage from over discharge. I could bypass the bms and discharge without it and let the lvc take over. But then again the lvc of the controller is probably 41.5 +/_ .5 v which is a little high for lithium. I feel with a properly adjusted lvc on the bms or on the controller will allow me to see 18ah.

[icecube57]

Every damn week its something new. When I bought this bike i was concerned about my crank being loose and my rear wheel had a little play in it. I adjusted and fixed the the crank but my bearings in my rear wheel were still loose and i wasnt up to the job of taking the wheel apart. I went out on a ride yesterday. Mid way through I hear ping ping ping ping. Then the wheel started turning super rough and started to wobble. Im like sheit. Atleast i was at the park and close to my car. I took it home and broke the wheel down bearings came rolling out. The was alot of dirt and grit in the bearing grease in and in the race. The bearing cage was gone ... literally chewed up into little fragments. The way the wheel is pressed together i couldnt replace the bearings I hopped on craiglist and found a donor bike that matched mines as far as speed and components. I swapped the rear wheel. This one was a little bit wider i had to stretch the frame. I also had to readjust the rear gears. But it smooth and quiet now and not gritty when turning and its tight no lateral play. Rode 20 miles 6.7AH consumed. my only problem now is where the rim is spliced together it isnt smooth. Ill get some sand paper from work and smooth it out so it wont ruin my pads... My old free wheel looks like it has been chewed up the teeth on the sprokets are just straight fubar. The new freewheel is in almost virgin shape. Its the exact same free wheel but it seems smaller and it feels smaller while pedaling. My high gear is a little bit tough but the low gear is way way to easy its like pedaling with the chain off ... i count the teeth they are the same they just look different... The new one has 14t on the lower but it measures smaller than the shimano on the other wheel and the high gear on the new wheel is larger than the old one but yet i still count the same amount of teeth....thats it for now. I officially commission my bike for night time 10pm and 7am commuting tommorrow 6 miles... 14 round trip. Different return trip. Wish me luck.

[The Stig]

Congrats on the newly commissioned bike, and good luck!

[Hyena]

Sounds like you're having a rough run!
I have the exact same bike and my rear wheel has a bit of sideways play in it too. I took the wheel off and tightened the nut just inside the cassette and that fixed it. First off I made it too tight and the wheel would barely turn, but after backing it off a bit I found a good compromise where the wheel had no play in it and would freewheel for half a dozen rotations before stopping.
I'll keep an eye on it though as it may end up the same as yours. For the price of the bike you can't expect much I suppose, and it's a good excuse to fit something better when it does fail.

[icecube57]

My commute in was fine. 6 miles 4.5 AH... the only reason it was that high is because the wind was 5-10mp blowing in all crazy directions. Kinda level and downhill most of the way. My average speed was 19mph i peaked at 36 mph. The motor held up fine. As long as there was a running start before hills... it glided over them without much effort. Never dropped below 15mph. My commute back was 6.7 AH. Same wind. Same route. Long medium grade hills. It was 42F out side which is probably like summer time for most of you. But the motor stay cool and solid no performance fade. I had the throttle wide open the whole way. On the way back I had a anderson pull out of its connector. Bad crimp. I replaced and soldered it back in. Luckily it happen in the level home stretch. I had my kit and fixed it on the spot. Some reason my battery pack wanted to slide off my rack to. I realized I didnt strap it in tight enough so that was the cause. I say it was a success. It took about 2 1/2 hours to charge at work. Not bad. I could get used to this. Not that I needed to charge but the fresh off the charger battery did help me through those hills.

[icecube57]

Ok... so Ive have been commuting to work on my bike. Its alot different on the road vs trails in parks and stuff. We have nice flats and rolling hills. My bike is always in the upper rpm and never lugging slowly up any of the 5-10% grade hills when I have momentum in my favor. My average speeds are hitting over 25mph and peaking around 36mph. No one is really on the road at 10pm or at 7am with the route I have chosen. If there is I get alot more respect on the road vs no motor at all. They think twice before passing me... one its not worth it because Im going so fast that by the time they pass me the stop sign or stop light is coming up. I dont ride like I own the road. I stay pretty close to the white line but if i know the coast is clear im all over that road. Im not saying my build experience has been easy or uneventful. Those of you who down Golden Motor their support or because they repackage old stuff. Im sorry you had those issues. But I personally have put over 500 miles on this motor and would recommend it in a heartbeat. My bike peaks at 1800-1900 watts constantly. My 6 mile commute pull just over 5AH out of my pack. My commute is WOT 100% of the time. Im even going fast enough to draw less than 5-10A when im going 30+mph. It pulls me fantastically 20+ mph up hills. This is with a 400lb payload including me, motor, bike, battery, and my book bag. I havent rode many motors only 3. But it beats the BD-36, Brushed Clyte 409. Probably faster and stronger than any 400 series Clyte. Probably an overstatement. But I say this because ive never been more confident in this build before. There is one thing to play around and go around the block but putting it to use in the real world .. it not only proved its self not only in the trial and test phase but it performed even better in the field. If I do anything else with this build... I would maybe upgrade to 36-72v 40A controller which is a step up from the 48v 30A I would like to get more torque so i can get to my top speed a little quicker and add an 8-12AH booster pack 18-22v booster pack to enhance the first half of my ride.

[icecube57]

OK so I left my bike on with the throttle lock on and I come back several hours later to move the bike one day it doesnt work. (Throttle lock that is) and this is what happens. If the controller comes on I can turn the throttle about 75% and the motor runs with the wheel off the ground. I can slow down and speed it up. If I go to 100% throttle the motor stops and the controller crashes and I have to unplug it several times to get it back going again. Sometimes I get lucky and it runs fine without issues and i can actually ride. But other times it just sits there and does nothing. I cracked it open and I found the afterbirth of some magic smoke. Pictures are below. I also used google and made a cheap camera mount for my digital camera.... Super sturdy too as for the motor controller... eh.... I called the guy up at Arizona Ebikes. Explain the situation. Sent the pictures of the fried components in the controller... He is out of my controller that I currently have but hes going to send me an old school black case GM Regen Controller. Not the new sensorless one but the old school larger one. He says its slightly larger than the one I have now. Its 1000w 48v 30A. I think its that one with the funky regen issues. But i was looking to get a regen controller anyway since my brakes are sub par. Hes upgrading me free of charge and should be shipping it out tommorrow or monday at the earliest so i should have a new controller by the end of next week.

[icecube57]

Two videos different routes. Real world conditions.

[icecube57]

Despite my bad controller Ive been riding my bike like its a rental. I did range test today on the Silver Comet Trail by my house.. I did 35 Miles total. I rode 17.5 miles and consumed 6.5 AH. I maintained a speed of 18-20mph. On the way back to my car I did WOT for the last 17.5 miles. I maintained atleast 30mph. I peaked up to 33-34mph. I consumed 9 AH. For a total of 15.5 AH. My bms cut out just as i was getting off the trail. It was only at 46v under load. I am going to bypass the bms on my next run to see if i can get anymore out of my pack. So on the first part.. if 48v is my nominal voltage i did 18wh per mile on the way back i did 25wh per mile for an average of 21wh per mile. This is flat terrain 1-2 percent grade at most in places.

[dnmun]

why not just fix the controller? it hasn't ruined your motor yet and is still fixable.

maybe you can get one of the infineon controller for 48V and use it to see if you get the same performance.

do you know for certain that the BMS on the battery was shutting down for LVC or could it be the controller LVC shutting down because that input power resistor is burned up and the voltage regulator is running so far out of control it cannot provide a good 5V source for the zener used by the the shunt voltage reference. which is what appears to be happening. imho.

[icecube57]

The controller is bad yes, Im getting a GM Regen Controller to replace this one RMA through the company i bought it from.

But Its the bms cutting out early on the battery because the last time i tried a full discharge it stopped at the same exact AH which was 15.5. But the controller was good on my last full discharge. When I tested the cells through the bms they were rather high at 2.7. some a little bit lower but not near the full discharge state of 2.2.The voltage was around 46 when it cut out.. The lvc on a 48v controller is normally 41 sometimes lower if you get one custom made.

The vendor says its normal that the bms is protectecting the pack. It doesnt lug or anything i still have good solid 30mph performance all the way to the 15.5AH mark and then it cuts out. But i think the lvc is set so high to prevent full discharge from damaging the cells and pack. Its well designed and i can see why the vendor sets it that way. But I ordered a 20AH pack and im getting 75% of that and verified by a volt meter that the cells arent fully discharged. Im going to charge with the BMS and discharge without it and either let the lvc of the controller kick in or manually back off when it hits 40 to 41 under load i bet i get better results.

[dnmun]

i see, this is a different thread from the one i responded to originally. i had only seen the new thread you started on this. anyway, i thought your FETs had burned up too. you just soldered up the trace on the side when the resistor shorted out on the case and melted that trace? that was what you asked about originally i thought.

anyway, i suspect your power resistor may be different in value from what it was originally, so you could check them with an ohmmeter and if they are far off in value from the color code value, then replace them, and you could check to see if your 5V reference bus is really at 5V before you take the resistors out. but if you can certify that, and voltage regulated on the 12V, i expect that controller would still work since it just shorted out on the case when you jumped a curb or hit something. you can cut a small square of polyethylene off the side of a milk jug and slide it under there to support the pcb to keep it from happening again.

they most likely have the regen feature somewhere available on that pcb too. you are getting a similar controller?

[icecube57]

The guy that i spoke with says its a old school 1st generation regen controller. The new regen controllerss are small and compact. The 1st generation are black and a little bit longer than the current 48v 1000w controller I have pictured on my bike. I looked at the board really closely after i cleaned it up a bit and it seem that the trace on the bottom edge of the board had something inline with it and then it linked up with the leg of the resistor on the left. the trace above it seems was fine. I took solder and made a connection between the burned trace and the bottom leg of the resistor it seems to have gotten rid of the erattic behavior... not totally but its better. It seems now if i plug my pack in a leave it a min i can ride but i cant plug it in and ride off immediately like its takeing time to charge something up or like you said regulate the voltage properly.

[dnmun]

yes, you can actually go check the voltage on your controller while it is plugged into your battery. with the hall sensors and phase wires still connected

you will see places on the pcb where they have +5V printed next to pins and holes in the pcb.

you can put the voltmeter on there, black lead to ground, and it should read 5V.

if not then you have a problem with the power resistor that got all discolored when it burned up. it burned up because somehow that resistor leg or maybe the edge of the pcb where that trace is, touched the case and shorted out the full battery voltage, so that resistor reached high enough temperature that the inside turned into plasma and the heat from that plasma discolored the inside of your box.

i suspect if you replace the resistor with the proper one, or even a little higher resistance, your voltage regulator will work again and your controller will behave again. make sense? other things coulda burned up, check the second resistor too, but it does not look dead. just close, so check it anyway. that is where you can read the 12Vbus too i think. across that 2nd resistor.

you really should make a plastic cap / tray to go around the end of the pcb there. like i said, a small polyethylene plastic square that includes the corner of the jug a little, around the end and underneath it for long term prevention. also cut off the long legs of the new resistor too.

before you put the pcb back inside, test the 12V and 5V before you put it back inside the box and if you get those back at normal, that is likely all it is. but i'm just guessing.

[icecube57]

I think i can vouch for the ebay vendor that sold me my battery pack. I felt kinda cheated about the capacity of my pack but the more i read the threads i began to understand that 15-16AH out of a 20AH pack with a BMS is conservative but respectable. Its taking it to the safe limit of 3,6 of 3.7 volts a cell to prevent damage to the pack. If you want to tap into that reserve you can but you better not take it below 2.1 or 2.2. Its good to know I more than likely have that 20% reserve left in my pack. I actually just got done wiring my pack with andersons. I can now charge and discharge with the bms. I can also now discharge without the bms if i get stuck out some where and im on that last leg home. I know my pack limit with bms is 15.5 AH so thats why i will try and limit myself to. I just also checked my pack and it pretty well balanced All my cells read 3.72 to 3.75 off the charger. I still have one cell thats a little low at 3.68 but its respectable its within 2% of my highest reading. I will give it one full true full dischage to the lvc of the controller which is 41.5. Right now the bms is cuttin out at 46v under load voltage.

[dnmun]

you should be able to discharge down to 35V without damaging your pack if no cell drops below 2.1V.
don't wanna replace that 27 cent resistor because your bike is a rental?
if this is how GM makes controllers, you will have a problem like this again i bet.
i don't really think much is wrong with that controller except the power resistor.
you could see if it is possible to change the reference voltage in the BMS for the low voltage shutoff, to discharge farther, but that way is dangerous if you drop it below 2.1V/cell
BOL,dm