StefEbike for my wonderful disabled wife

[thundercamel]

Thanks Chalo, Good to know you haven't seen steel ferrules either. I at least did learn to grind the housing ends flat from Sheldon Brown in time for the repair.

Looks like I forgot to mention that I helped build another eBike in April; this time for my wife's stepdad whom I get along well with. I sent Tom a few used bike listings that would have made good conversions, but he wanted something new. This is what he picked out from Walmart with my approval (the first one had tiny stanchions, which was the main problem with my Walmart bike). The Sidewinder is the same as StefEbike, but two generations newer. I warned him that eventually these stanchions will bind up as well, but we can swap the fork out then.

We immediately swapped out the seat, handlebars and stem.

The motor, controller, and charger came from the black folding CEMOTO bike PHAT-E that I had recently upgraded. The spokes I recently purchased when I rebuilt the wheel in the other folding bike GoldiWatts, but then that bike also got a direct drive motor. Tom didn't mind the slower KV of the free geared hub motor. I wanted to paint the parts black, but never had time. The Sidewinder came with nice 2.25" wide tires, but the wheels/rims I laced the motor into are only about 20mm inside width. I would have been happier with 25mm or 29mm for wider future tires.

Since LG MJ1 cells that I like seem to be no longer available, I did research and chose Samsung 50E 21700 cells for longevity/cycle life again. This required me to buy new 21700 sized plastic spacers/cell holders, and the adhesive paper circle insulators for the positive ends. I was very mad when the price of the cells jumped from about $5 to $6.67 per cell right before we bought them, and now they're out of stock! I didn't take many pictures, but I used self resetting poly fuses on each balance wire for the first time. Wrapped the pack with smart JBD BMS in plastic sheet for protection, padding, and heat shrink. I also used new silicone insulated wire I bought. (No more speaker wire!)

The electrical performance is just like the original CEMOTO bikes were, but with a longer lasting battery. With only a 10s 36 volt battery, lower KV geared motor and 15 amp (500 watt) controller, it gets you up to 10 mph and then I saw only 20 watts on the meter by 18mph or so pedaling firmly. Back EMF! Tom mostly wanted the motor as a backup to get home if his health acts up at all during a ride.
Pretty fresh looking!

Tom followed us around Moraine Hills state park (McHenry Dam) and kept up with my speed racer wife quite well! He's been buying accessories since.

I bought a power meter for him, and he made this box for mounting the display. Tom also bought of his own accord the same head light and tail light that I've been getting, and wired them to the controller output himself with an inline fuse, connector and switch by the display.

Rack too. Hopefully he moves the light to the back of the rack like I did with PHAT-E.

I've been playing Farming Simulator 2013 with Emmett, and he pointed out the wheat

Bonus points if anyone recognizes this mansion. I don't expect anyone to be from my area.

 

[thundercamel]

Lol, I just noticed that the head tube is made to look like it has a tapered headset, instead of actually having one!

 

[E-HP]

Bonus points if anyone recognizes this mansion. I don't expect anyone to be from my area.

https://www.lake-villa.org/mansion/

 

[thundercamel]

There may be a difference between recognizing the mansion, and using google That's it though! Strangely, I'll always remember it as the place I went mud wrestling a long time ago.

 

[E-HP]

There may be a difference between recognizing the mansion, and using google That's it though! Strangely, I'll always remember it as the place I went mud wrestling a long time ago.

Sorry, I broke the rules . I don't recognized the mansion, but I do have memories of mud wrestling, LOL. Wow, that was way back. :lol:

 

[thundercamel]

Oh baby! Bought from here. Testing four of them at random now.

 

[thundercamel]

Results are in!

 

[Chalo]

Impressive results! Those will make a nice energy-dense pack. What welder are you going to use?

 

[thundercamel]

I'll be using the same Malectrics welder and 8mm nickel spool that I bought in 2018. Have used them to build 5 packs so far, and there's still plenty left on the spool.

It's tempting to build a 20s15p pack rated at 100 amps continuous 250 peak, but my goal is endurance with the Lynx recumbent. It will be 14s21p so I can use my existing 10a charger. Wasn't there some consideration to large groups in parallel, in case one cell gets a short the other cells dump energy into it or something? I will be using only one 8mm strip to combine each group in parallel, same as always.

 

[99t4]

So I finally tried out the EBS pad on my bike's controller in an effort to find regenerative braking. Fechter suggested I check it out, and I've found some references in other threads as well. When the controller is on, the EBS pad floats to 5 volts. Pulling it down to ground does not initiate regen, nor does it enable the brake levers to initiate regen. In fact it exhibited no behavior other than making the motor jump forward every time a brake lever was released. Totally bizarre!

Were you ever able to enable regen from this controller?

I ask because I recently bought a used 1500W Ebikeling kit from local online classifieds and want to use it for a new project but would really like to include regen to help in my hilly neighborhoods.

 

[thundercamel]

Not yet, but I only tried pulling EBS to ground while spinning the wheel full speed in the air. That was for safety reasons, since I wasn't sure what it was going to do. I should probably try again while actually riding, and expect it to burst forward when I release the wire.

 

[thundercamel]

On the controller, I can see a pad on the board marked "EBS" with no wire attached. It may actually be capable of regen but just doen't have the wires hooked up. The layout looks like the typical "Infineon" style, but hard to say based on just the looks.

So I finally tried out the EBS pad on my bike's controller in an effort to find regenerative braking. Fechter suggested I check it out, and I've found some references in other threads as well. When the controller is on, the EBS pad floats to 5 volts. Pulling it down to ground does not initiate regen, nor does it enable the brake levers to initiate regen. In fact it exhibited no behavior other than making the motor jump forward every time a brake lever was released. Totally bizarre!

I'm going to have to do more research and get a further understanding of this controller. I already have a couple Infineon threads to read, but am open to suggestions :wink:

Infineon Controller Technical
XPD: open-source keywin e-bike lab replacement

Update 1 of 3:
Retraction!!! fechter was absolutely correct, and I'm very annoyed that I didn't have regen working since 2019!

This is on the Ebikeling 1500 watt 15 FET controller that I bought in 2018. The mistake I made in 2019 was that I had only tested in the garage, and not on an actual bike ride. Pulling the EBS pad low (connecting it to a ground wire) DID enable regenerative braking, and should be done before turning the controller on. Then pull the brake lever, and after a delay regen braking will fade in providing your battery voltage isn't too high (fully charged).

I've seen peaks of over 10 amps while monitoring the smart BMS. I believe that it was that 1-2 second delay that didn't let me notice regen working on my garage test, or I made some other dumb mistake like not grounding the EBS pad BEFORE turning the controller on. My apologies to fechter and 99t4!

 

[thundercamel]

Update 2 of 3:
It was this video that made me realize that regen has a delay, and that I should test it again on an actual ride.

[youtube]7gL5y96-GCo[/youtube]

When he explains that his controller requires connecting the X and DS pads together at 2:17, I realized that I've seen that circuit board layout before in my wife's bike! I added enough solder to bridge the X and DS pads, and REGEN WORKS THERE AS WELL!!!

The previous Low Voltage Cutoff mod that I added did cause regen to not function until the battery was about at 2/3rds State Of Charge. I'm going to change that resistor I added to be on an external switch to function as a reserve tank in case of emergency.

The regen behavior on this controller also has a delay, but doesn't seem to fade in much. Also have seen peaks of over 10 amps.

 

[thundercamel]

Update 3 of 3:
My biking friend Justin always seemed to like my Lynx recumbent best on long trips. When I asked if he wanted a similar Short WheelBase recumbent, he said he preferred the bikeE Compact Long WheelBase design better (his mom's bike), and could even maneuver at crawling speeds. In my head I scoffed those possibilities especially with no easy way to add front suspension, but different strokes for different folks.

In December I found this bikeE on Craigslist for $250 in Madison. His brothers and dad each chipped in $50 and my friend Matt picked it up. Looked to be barely used and in great condition! Bought this Voilamart 26" 1000w kit for $260 and the controller again turned out to be sine wave, like the 1500w kit I got for PHAT-E.

We immediately tested the Kv which came out to 8.87; the slowest direct drive I've encountered yet. We put that motor/wheel in GoldiWatts since it's power limited with a 36 volt 500 watt controller anyway. The 26" 1500w 9.3Kv motor I JUST put in GoldiWatts moved to my Prancing Pony since I wanted to downsize from the 700x38c tire for more air volume. (Yes I lost the rear brake but I now have regen functioning as my rear brake. In an emergency straight line stop there's so much weight transfer that the rear locked up on dry pavement anyway.) The two ebikeling motors I have are the fastest Kv available to us at 11.6, so I rebuilt the 700c Prancing Pony wheel into the 20" Alex DM24 wheel I had previously used in my Lynx. Speaking of names for the new bikeE, my first thought was bikeEbike!

We do need to grind some space on the axle nut for the derailleur to clear, but got it on a couple threads for a test ride. Justin is borrowing the 14s6p LG MJ1 52v 21ah pack his brother built. We lost the internal geared hub for higher speeds, but I put another 11-28t DNP freewheel on, and the front chainring is at least 46 tooth. Could only pedal up to 18mph or so. Test rode 20 miles starting at dusk that night, and it was AWESOME!!! It accelerated a little faster than my Prancing Pony, even though it's only 26 amps compared to 31. Top speed is 33 mph, so I passed him just barely at my top speed, all the while burning more watts. Will have to revisit vs. the Lynx.

Even though the tiny 16" front wheel is unsuspended, there's so little weight on it that I didn't mind going over bumps. We jacked the Cane Creek AD-5 rear shock up to 240psi and it was as smooth as a Cadillac!! It definitely has room for a 2.4" rear tire, but after riding I don't even see the need. Maybe more knobby traction in the loose gravel later?

The first time I tried his red bikeE CT it was quite awkward and rough over the bumps. Maybe after getting used to the Lynx recumbent, this new bikeEbike was total cake to ride! You can slalom left and right very quickly. The wheels move left and right while your body stays in place as a fulcrum. Rim brakes were great; hardly any sound and quite strong enough. We had forgotten to raise the handlebar back up after transport, so combined with the derailleur I will test pedaling later, but expect it to be strong pushing against the seat back. Can't wait to see the watt hours per mile in that small efficient wheel!

Compared to my Lynx:

80mm 14ga spokes in the 20" Alex DM24 wheel I had previously used in my Lynx.

 

[99t4]

On the controller, I can see a pad on the board marked "EBS" with no wire attached. It may actually be capable of regen but just doen't have the wires hooked up. The layout looks like the typical "Infineon" style, but hard to say based on just the looks.

So I finally tried out the EBS pad on my bike's controller in an effort to find regenerative braking. Fechter suggested I check it out, and I've found some references in other threads as well. When the controller is on, the EBS pad floats to 5 volts. Pulling it down to ground does not initiate regen, nor does it enable the brake levers to initiate regen. In fact it exhibited no behavior other than making the motor jump forward every time a brake lever was released. Totally bizarre!

This is on the Ebikeling 1500 watt 15 FET controller that I bought in 2018. The mistake I made in 2019 was that I had only tested in the garage, and not on an actual bike ride. Pulling the EBS pad low (connecting it to a ground wire) DID enable regenerative braking, and should be done before turning the controller on. Then pull the brake lever, and after a delay regen braking will fade in providing your battery voltage isn't too high (fully charged).

I've seen peaks of over 10 amps while monitoring the smart BMS. I believe that it was that 1-2 second delay that didn't let me notice regen working on my garage test, or I made some other dumb mistake like not grounding the EBS pad BEFORE turning the controller on. My apologies to fechter and 99t4!

My Ebikeling 1500 watt 15 FET controller looks similar. Did you simply solder a jumper wire from the EBS pad to a GND pad?
Here are the pads on my board:






Wondering if any GND pad can work, note that there are several visible in the second photo.

 

[thundercamel]

Yes, any ground pad will work to jumper a wire between and connect to the EBS pad. You'll notice in your picture that entire field of green around the EBS pad is a large trace for ground, and connects to all of those ground pads.

I actually ran the EBS pad to an external wire through the rubber gasket, since it was for testing at first.

 

[99t4]

Thanks, that helps, in my wanting to make sure to add the jumper in the correct place for the desired effect without letting out any magic smoke.

I actually ran the EBS pad to an external wire through the rubber gasket, since it was for testing at first.

I will probably do similar.

 

[thundercamel]

I moved to a new house!

Had to find time in between all the boxes to assemble my 5kWh pack for the Lynx recumbent. I was very tempted to build a 20s15p pack since I bought 300 cells, but chose to do 14s21p instead. My goals are long distance, it already gets up to 40mph, I already have a 500 watt 14s charger, and I may possibly use this for a 6kW boat outboard motor in the future, which expects a 48 volt pack.

The 21p also fit my box design without needing any triangulation.

The balance wires PTC fuses on the last pack have been working well, so I used them again here.

Trying to make 150 amp terminals was a new challenge for me. I know some people spot weld tabs to hang off the edge, and I still may try that in the future. I separated this 4 gauge OFC cable into groups, and cut them to length. Longest two groups got soldered to the outer edges, and worked my way to the middle. Maybe should have done it inside out.

Tried 20 smaller wires on the negative side. Turned out to be even more of a hassle than the one large cable.

I just have a 60 amp JBD BMS for now, and a 100 amp shunt power meter like the other bikes. The dollar store no longer had plastic cutting sheets, so I used these sheets made for drawer liners. They're quite tough.

50 POUNDS?!!

I have aluminum sheet and a plan for a battery box, but summer was already upon me and I needed to get riding! Whipped up a wooden box, and made it 10 miles before the old flexible metal straps broke from fatigue. The bike tried to run over itself 3/4" x 1/8" steel is much nicer, but I need to raise the rear higher for ground clearance Clarence.

The attached KT48ZWSRKT-SJT02L 45 amp 18 fet controller and KT LCD3 display came with another motor kit that I was gifted earlier. When used with an SW900 display or no display with a jumper instead, power would taper too much as the speed rose. Now with the included LCD3 display it peaks at 45 amps near 0mph, and continues at 42 amps until the system is voltage limited (back EMF). The rows where speed and power usage should be aren't displaying however, though the odometer is working. I think there's a factory reset in the parameters, but it's not a good first impression for the controller/display combo.

On a full charge, the GPS app on my phone shows 42mph on level ground, which I guess is good since I have to ride 6.0 miles on the roads to get to the only bike trail nearby. I can contribute pedaling up to 30mph, and sprint up to 35mph, where my effort becomes meaningless and I need to worry about the balance/stability of the bike more. I miss the abundance of forest preserves that Lake County had, but at least that one Prarie trail by me goes all the way down the Fox River past Aurora, and connects to many trails in the Chicago area. Add a headrest and some storage, and I might finally be able to do my 140 mile Madison loop this year!

P.S.
The four cells that I tested before assembly I didn't use in the pack. The 294 cells I used were untouched, and I didn't calibrate the 14 voltage readings in the JBD BMS this time. The voltage difference between the groups read about 0.005v upon assembly, and read 0.004v after charging. Voltage does sag 2-3 volts under the 42a load, which is more than I was expecting, but no problem. I was able to bury the temperature sensors deep in the middle of the packs one on each side, and the temperature barely climbs under extended use.

 

[APL]

Jump'n Judy, that's a big battery thundercamel!
Must make the bike super stable though, right? If you plan to do that kind of distance then I hope you take along the pump and patch kits, etc. :wink:

Speaking of which, looking at the map you show, .. it goes right by my neck of the woods, just outside of Madison Wi.! Looks like we could maybe hook up one of these days. :thumb:

 

[thundercamel]

Thanks APL

The stability doesn't really seem affected, to be honest. It was certainly more unstable when the straps were flexible, and the box would swing around (like a sack? lol). It's still tricky at super low speeds, and still wobbles a bit when sprint pedaling at 35mph. The toolkit I made does have patches, pump, co2 inflator and tools in it thankfully. Just need a place for my lunch, jacket, ect.

For sure we should meet up! My friend (icon on the map) lives in Fitchburg.

 

[thundercamel]

Sorry for the absence; raising kids takes up a lot of time Right before the winter my brother in law dropped off the PHAT-E bike (CE Moto) I made for him two years prior. It was an experiment at the time to see if he'd like an ebike over the 2-stroke bike he was using to commute to work every weekday. Well he hasn't use the gas bike since (as far as I know), and the 14s3p battery that fits in the frame was being charged twice every day. The 30q cells would now sag from 4.1 volts at rest to about 3.3 volts under full throttle, which is was 30 amps. I dragged my heels all winter making a new larger battery somehow work for that bike.

Made my own "downtube" out of aluminum c-channel.

Bought 3 boxes of 3400mAh unwrapped panasonic cells for this and one new project.

Channel 2 on this tester always reads high.

14s7p for 52 volt 24.5 amp hours

This is the third battery that I've used PTC fuses for the balance wires. They've been working fine.

Extra precautions with the unwrapped cells:

Reused BMS and Maxi fuse poking out the front:

Separate fuse for the charging port:

Folded and riveted a sheet aluminum cover:

Other work performed was:
1. Re-lace the MTX39 wheel he bought using Sapim Strong 13/14 single butted 157mm spokes. Anti-seize on all threads and nipple seats
2. Shunt mod the controller to 40 amps
3. Enable regen on the controller, wired to "horn" button since brakes are hydraulic with no switches.
4. Added torque arm v4.
5. Added a DC power meter in a 3D printed enclosure.
6. Put the motor controller in the frame where the battery used to be. I flattened the mounting tabs and attempted to get physical contact to transfer heat to the frame, but I hope the controller doesn't overheat.

It's back in use every weekday, and I need to do a check-up on the spokes and new screws haven't loosened.

 

[E-HP]

Nice update! A lot more riding, and a lot less charging. Your battery builds are slowly inspiring me towards my first battery build. Kids are all grown up, but still have too many projects; so easy to procrastinate.