Search found 14948 matches

by fechter
Jun 20 2021 12:05pm
Forum: EBike Non-hub Motor Drives
Topic: BBSHD mod firmware
Replies: 1
Views: 97

Re: BBSHD mod firmware

Check out this topic:
viewtopic.php?f=28&t=100064

The PAS priority over throttle is very annoying. At some point Bafang figured that out.
by fechter
Jun 20 2021 11:58am
Forum: EBike General Discussion
Topic: Do these cables cause problems?
Replies: 13
Views: 218

Re: Do these cables cause problems?

The USB to serial converter can also cause problems. With a different controller, I had one that did not pull low enough to read as a zero to the controller and wouldn't talk. By adding a resistor from the TX line to ground, I was able to tweak it enough to work. Some converters may work better than...
by fechter
Jun 20 2021 11:53am
Forum: Motor Technology
Topic: Tesla model S plaid motor 30 lbs, 400 hp perfect high power ebike motor?
Replies: 12
Views: 534

Re: Tesla model S plaid motor 30 lbs, 400 hp perfect high power ebike motor?

I bet it's just the rotor that's 30 lbs.
Tesla Plaid Rotor.JPG
Tesla Plaid Rotor.JPG (36.39 KiB) Viewed 77 times
Just the reduction gears look like 30 lbs. The whole motor has to be much more.
Tesla Plaid Motor1.JPG
Tesla Plaid Motor1.JPG (72.98 KiB) Viewed 77 times
by fechter
Jun 20 2021 11:41am
Forum: Motor Technology
Topic: QS motor shaft wear
Replies: 13
Views: 437

Re: QS motor shaft wear

That looks like it should stay stuck for a while. The only thing I would worry about is if there is any play at all on the shaft, it will allow bending around the welds and they might fatigue over time.
by fechter
Jun 20 2021 11:35am
Forum: EScooters/EMotorcycles
Topic: Electric motorcycle battery/Kelly controller panic!
Replies: 8
Views: 132

Re: Electric motorcycle battery/Kelly controller panic!

I would immediately suspect your voltmeter. Replace the battery in the voltmeter. Try measuring a known voltage from something else like a wall outlet. The most you should see on a 20s pack is about 84v at end of charge. Is the breaker staying on or tripping? I'm not clear on what exactly is shuttin...
by fechter
Jun 19 2021 6:18pm
Forum: Battery Technology
Topic: What AWG wire for 52v battery?
Replies: 10
Views: 287

Re: What AWG wire for 52v battery?

OK, that should work. You don't want to solder directly to the cell bottom. You can solder to an existing spot welded nickel strip. You still need to be careful not to overheat the cells.
by fechter
Jun 18 2021 12:46pm
Forum: Battery Technology
Topic: What AWG wire for 52v battery?
Replies: 10
Views: 287

Re: What AWG wire for 52v battery?

Are you planning to solder directly to the cells instead of spot welding?
by fechter
Jun 18 2021 12:43pm
Forum: EScooters/EMotorcycles
Topic: FINALLY DONE! 1970 Vespa 50s electrification project
Replies: 132
Views: 20981

Re: FINALLY DONE! 1970 Vespa 50s electrification project

Nice! What kind of top speed did you see?
by fechter
Jun 17 2021 8:55am
Forum: EScooters/EMotorcycles
Topic: Battery wiring for 100a trouble..
Replies: 6
Views: 203

Re: Battery wiring for 100a trouble..

Any idea what those terminals are made of? Spot welding may be difficult. Whatever those cells were made for must have had a way to connect them. It would be nice to see how somebody else connected them.
by fechter
Jun 15 2021 8:29am
Forum: EBike Technical
Topic: 24V low voltage protection or 18V controller
Replies: 2
Views: 88

Re: 24V low voltage protection or 18V controller

There should be a way to alter the low voltage cutoff but it will take a little reverse engineering. A 12v controller will most likely work without modification but the low voltage cutoff will be too low to be useful.
by fechter
Jun 15 2021 8:18am
Forum: EBike Build Threads
Topic: Hub motor as mid (illegalbike)
Replies: 59
Views: 3429

Re: Hub motor as mid (illegalbike)

Nice. Looks like that thing really moves. Those steps really gave the suspension a workout. Great design!
by fechter
Jun 14 2021 10:56am
Forum: Battery Technology
Topic: Does this BMS have balance resistors?
Replies: 4
Views: 140

Re: Does this BMS have balance resistors?

For sure the one in the picture has balancing resistors. The spec page states 50mA balancing current.
by fechter
Jun 13 2021 11:18am
Forum: EBike Troubleshooting
Topic: Upgraded Fat Tire bike stopped running, something seems Burnt!!
Replies: 7
Views: 218

Re: Upgraded Fat Tire bike stopped running, something seems Burnt!!

If the motor spins easily with the controller unplugged, then the motor is probably OK. You need a new controller.
by fechter
Jun 11 2021 11:56pm
Forum: Motor Technology
Topic: DIY Toroidal Axial Flux PM
Replies: 140
Views: 3983

Re: DIY Toroidal Axial Flux PM

I want one. Mine still has a vacuum tube and weighs enough to anchor a ship. I have an expensive Fluke Scopemeter at work and I'm not super impressed with it.
by fechter
Jun 11 2021 12:59pm
Forum: EBike Troubleshooting
Topic: Cycle Analyst V3 Speedometer doesn't show speed
Replies: 4
Views: 105

Re: Cycle Analyst V3 Speedometer doesn't show speed

Possibly they attached the speed sensing wire to the wrong place. Normally it would go to one of the motor hall sensor signal wires.
Installing a magnet on the wheel with a wheel sensor would be another way to fix it.
by fechter
Jun 11 2021 12:49pm
Forum: EBike Technical
Topic: Placement of thermistor
Replies: 3
Views: 117

Re: Placement of thermistor

Yes, just under the winding on the iron would be a good spot. I haven't had issues with noise, but I suppose it's possible. Since the temp signal changes very slowly, it can be heavily filtered to keep noise out. You can glue it in place with epoxy or silicone.
by fechter
Jun 11 2021 12:08pm
Forum: EBike Troubleshooting
Topic: Upgraded Fat Tire bike stopped running, something seems Burnt!!
Replies: 7
Views: 218

Re: Upgraded Fat Tire bike stopped running, something seems Burnt!!

Unplug the motor from the controller and see if the abnormal resistance to pushing backward disappears. If so, the controller is shorted. You can also check the controller with an ohmmeter once the motor is unplugged. Measure resistance from each phase wire to B-. Reverse the meter probes and measur...
by fechter
Jun 11 2021 8:47am
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 2107
Views: 147477

Re: la Nina rears her ugly head

lake mead.JPG
lake mead.JPG (94.23 KiB) Viewed 44 times
Currently at 36% capacity. They say it's the worst drought condition in 1200 years. The governor of Utah asked people to pray for rain. "While prayer doesn't hurt, it shouldn't be Plan A" (Dr. Fauci).
by fechter
Jun 10 2021 3:47pm
Forum: Battery Technology
Topic: Adding extender battery in parallel.
Replies: 8
Views: 178

Re: Adding extender battery in parallel.

Under the seat will be a good place. Well protected and the seat is too low to start with if you have long legs.

The capacity of the cells isn’t so important. You want the voltage sag under load to be close. Even if they aren’t I don’t think it’s going to matter that much.
by fechter
Jun 10 2021 9:39am
Forum: Battery Technology
Topic: Adding extender battery in parallel.
Replies: 8
Views: 178

Re: Adding extender battery in parallel.

I'm running a parallel pack on my Sur-ron made from Panasonic CGR18650DA cells, which are similar to the PF cells. My pack is 16s12p and about 30Ahr, so nearly equal to the stock pack. You can see some details here: https://endless-sphere.com/forums/viewtopic.php?f=10&t=101441 I wouldn't worry t...
by fechter
Jun 08 2021 8:45am
Forum: EBike Technical
Topic: Sur Ron: street legal vs "derestricted" vs "X" - acceleration?
Replies: 2
Views: 149

Re: Sur Ron: street legal vs "derestricted" vs "X" - acceleration?

As far as I know, all the X controllers will behave the same whether they are on the street legal version or the dirt version. They changed the controller at some date. The ASI can be programmed for much better acceleration, but you are limited by the battery. With a stronger battery, the ASI can gr...
by fechter
Jun 08 2021 8:39am
Forum: EScooter/EMotorcycle Build Threads
Topic: Electric Roadster
Replies: 143
Views: 8912

Re: Electric Roadster

Did you figure out why it went into a wobble? I've had bikes that did that at high speed. A steering damper can help, but shouldn't really be needed if everything is built right. I've heard that a loose front wheel bearing or loose swing arm bearing can cause this. Steering head angle also makes a b...
by fechter
Jun 08 2021 8:08am
Forum: Battery Technology
Topic: Running parallel battery pack. I need help please.
Replies: 36
Views: 743

Re: Running parallel battery pack. I need help please.

Heating is the limiting factor. Having very short leads will help as the heat can get dissipated by the battery on one side and the XT150 connector on the other side. For sure it will handle that much current for a short burst, but for longer durations it might get pretty warm. The amount of air coo...
by fechter
Jun 07 2021 9:50am
Forum: Battery Technology
Topic: Running parallel battery pack. I need help please.
Replies: 36
Views: 743

Re: Running parallel battery pack. I need help please.

You can run the packs in parallel. Just get the voltages really close before connecting. I have a similar setup on my Sur-ron. Two packs, each with their own BMS, in parallel. One BMS is a "single port" so it can protect during both charge and discharge. The other pack as a "two port&...
by fechter
Jun 07 2021 9:39am
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5510
Views: 639402

Re: Sur-Ron - New Mid drive Bike

Interesting, this is what I figured you can't trust those notches. I think there is misinformation about this as some videos say to align based on the notches. When you did align with a straight edge did you need to use those little tension bolts to adjust the wheel? Was your alignment pretty close...