I just completed an installation of 24 new 60AH GBS cells in my 7 year old C124 and it is running fine. The old cells were still serviceable but power and range was suffering.
The cell replacement was bigger than the big job I thought it was going to be - between getting all the cells charged and balanced on the bench-top and shuffled onto the battery tray. Then there were the estimated 400 screw removal and replacements with those 4-screw cell terminals and BMS connections. At least GBS now uses Torx-head screws. I also rigged a much improved syatem of restraint straps for both the 12-cell rows. CuMoCo did not restrain the cells well at all against swelling and so most of the old cells were visibly bulging.
I had only one glitch - after the first ride with the new cells last week, bad weather kept it in the garage, then yesterday evening, I attempted a trip out to the pub, but the scooter would, on any amount of slope, go 2-3 meters then shut off, to be repeated when the throttle was returned to zero and twisted again. The light on the Kelly was green, so I figured that it was another case of the BCU over-reacting to a minor condition. Fortunately, I have the BCU Access software and hardware which can do an OBD-style scan, configure, or-flash the BCU**. So I was able to immediately diagnose it as a open battery pack temperature sensor circuit at the connector to the BCU - which I was able to fix.
Why John and Eric programmed all these ways to leave a rider stranded over the most trivial detected faults is something I will never figure out. Could you imagine owning a car that shuts down every time a CEL code is thrown?
And while the big front fairing piece was off the scooter, I put LED headlight lamps in it - 50% more light at 25% of the power consumption!
The only thing left is to figure something useful to do with the old cells. I'm thinking of using them to build a UPS for my house - I figure they still have enough capacity to keep the refrigerator and (now all LED) lighting going for two days, - or in winter, the gas furnace and refrigerator and lighting going for one day.
Anybody else out there with a CuMoCo scooter still running?
**Only a few owners were able to get the BCU access and the BCU firmware before the "angel investors" of CuMoCo put a kibosh on it becasue they thought John Harding's programming, even just the compiled firmware code, was some kind of valuable intellectual property - which also went a long way to assure the failure of CuMoCO (and their investment).
My C-130 still works great!
You may be the only other owner of a CuMoCo Scooter still running!
I think what saved my bike is I had an early problem with the BCU and they sent me a new one.
They blamed the problem on the 12 vdc power converter getting too hot and frying the BCU.
I switched out a bunch of incandescent lights to LED to lessen the load and keep the BCU cooler.....Seemed to solve the problem.
I also do NOT keep the battery topped up.
If I fully charge the bike, it is right before I am going to ride it.
Then, after I knock off ten miles or so of charge I leave the bike in a slight state of discharge until I am going to ride it again. Only then do I top it up, if necessary.
At one point I was riding the bike 47 miles (both ways) to work, 94 total. I'd charge it up for the ride home while working.
I like the scooter but it was rather expensive.
Best of luck with yours!
Yes, the mounting of the 12V (actually 13.5V if I recall) DC-DC converter in the same box as the BCU was a design disaster and the cause of most scooters being retired. My switch to LED's (even the headlights) is why mine is still running. And yes, keeping the pack less than full is important - charging full only occasionally to balance the cells. I learned that a bit late. I even practice it on my Smart ED car.
The other items that have kept my ED running is the hardware and software to configure and re-flash the BCU. Wiring up voltage check points for each cell using the BMS wiring has been very useful. For example In the past couple months, the BMS has stopped balancing cell no. 1 but I was able to discover the problem before this cell was getting way overcharged and now I simply discharge this cell a bit (through a string of taillight bulbs) every few times that it is charged full.
I'm still hoping that there is still a cache of old C-124/C130 parts in Ann Arbor somewhere. I have been unsuccessful at contacting any former CuMoCo engineers.
Update... My C124 has seen 9 years of service and is still running fine.
The only major repair job was due to the hub motor armature losing its tight press-fit so that it developed a few degrees of stick-slip rotational play about the axle shaft and keyway. This produced a "clunk" when alternating between acceleration and regen braking, and also caused commutation errors so the regen braking would rapidly cut off and on- making a sound like a trucks jake-brake.
The repair entailed removing the wheel and hub motor side cover and shear-pinning the hub of the armature to the axle. The first attempt was drilling and tapping a hole for an M6 high strength bolt. This worked imperfectly as the there is not room for a tap wrench to turn the tap, so the hole was incompletely tapped. I ground a point on the bolt and tightened it down with plenty of threadlocker.
The second attempt had the tap bind and break off in the hole - so the tap now serves as a shear pin.
The third attempt used a 1/4-inch spring-pin through the hub into the axle - this is the repair method I would recommend for anyone else doing this.
I hope I didn't weaken the axle too much drilling those holes...
My Scooter is still running fine on the original battery pack.
I only have about 6000 miles on it though.
I work from home and don't take many trips on it.
I reprogrammed the controller to get a little more zip out of it.
It is a bit twitchy off the line but is much better in acceleration.
Best of luck!
My C130 was still running in March. Unfortunately with working from home and everything shut down, I didn't touch it until this week. That's when I noticed that several of the purple rectangular covers had come off and even some of the turquoise round caps. Not sure what happened. (Mice got under the seat at one time, but I cleaned them out and it still ran.) When I turn it on, it shows that it's almost fully charged but the red light slowly flashes. Any thoughts?
My 9 year old C130 was running fine last March. Then the lockdown hit and I didn't use it for six months. Unfortunately I think mice got into it. Some of the purple rectangular covers have fallen off as have some of the round teal caps. The main fuse is blown. I'm not sure what to do with it. I don't have the skill set to tear it apart and would it need to be reprogrammed? Any thoughts? If it's not worth saving, how do I get rid of it?
Try try again for success
My C124 is 10 years, 4 months old. Still running better than it was out of CuMoCo's now long-closed shop. Mileage not certain as the speedometer was replaced a couple times before I realized it was a too-long speedometer cable causing the failures. The mileage stored in supposed to be non-volatile memory of the BCU somehow got reset too. Probably about 50,000 miles.
The only failed item is the No. 1 cell channel of the BMS. It no longer balances this cell, so every couple full chargings I have to discharge the No. 1 cell a little bit through the cell voltage check points (which I installed right after taking delivery) or that cell it overcharges.
I am keenly interested in a salvaged BMS and BCU and associated electronics from anybody's C124 or C130 being discarded. Cheers.
Which fuse is blown?
The round cell covers are pressure relief valves. While the new cell design has a cover and spring so the cover closes after any excess pressure is released, in the old cells, the cover just popped off. Usually the covers pop off for a reason - an over-discharged cell will swell and the pressure buildup will pop the covers off. At any rate, if the caps are off for very long, the cell is ruined. As far as the flashing, what was the flash pattern? See the list below.
Bike is operating normally
Continuous Short Flashing
Motor is disabled. Side stand is down,
brakes are engaged or charger door is open.
Continuous Long Flashing
Bike is charging in “bulk charging” mode This is the normal operation for charging the bike. First the
bike enters bulk charge mode and then goes into balancing mode.
1 Long Flash/1Short Flash (continuous)
Bike is charging in “balance charging” mode
3 Short Flashes
Pack is getting low Look for a charging station soon
3 Short Flashes / 1 Long Flash
Pack is empty Look for a charging station immediately
3 Short Flashes / 3 Long Flashes
Low Voltage Cutoff has occurred - one or
more cells are dangerously low.
2 Short Flashes / 1 Long Flash
Bike control systems are starting to get hot.
Available power is reduced by 30% until the
bike cools down.
2 Short Flashes / 2 Long Flashes
The motor is too hot. Available power is reduced by 60%.
2 Short Flashes / 3 Long Flashes
The power leads are too hot. Available power is reduced by 60%.
2 Short Flashes / 4 Long
The batteries are too hot. Available power is reduced by 60%.
2 Short Flashes / 5 Long Flashes
There is a broken or malfunctioning temperature sensor.