Rescue Motor - Aotema (Wilderness Energy BD-36)

[DrkAngel]

.
... Schwinn Candis\WE 600w brush front hub combination tentatively approved.

Will perform 1st actual trial of potentiometer, inline of throttle signal wire, as artificial voltage-throttle regulation.
Runs nice and smooth @ 37V, tested @ 25.9V and judged as satisfactory for pedal assist mode.
Have lots of nice Samsung 37V BMS protected packs.
Will regulate below 20mph, possibly ≤15mph, for max range and comfort\safety.
TURBO button will bypass potentiometer for various "emergency" uses ...

Still need to add speedometer and warm dry day for full evaluation, before properly mounting controller, battery etc.
Will also reverse handlebar stem for more comfortable upright posture.

Possibly fenders and\or rear rack? ... front basket?
Final task will be swapping Candis rim and tire onto WE motor.

Present controller is 50V capable so ... might take a trial run with 44.4V battery.

 

[DrkAngel]

Schwinn seems best at 25.9V
Estimated at <350w output (down from 600w @ 37V).
It appreciates pedal assist and the 40-14T max pedal gearing seems suited for sub 20mph.
and
Of course, I can always swap in the 37V packs for ... higher speed cruising.

Paired a couple "Floureon 7S 5000mah 25.9V 40C Lipo Battery <$60" for my 25.9V test drive. (fit in nice small bag, but could mount permanently between frame rails)

Actually got 1 pair for $30 each so, $60 for 25.9V 10Ah Lipo with 15+ mile, motor only, range.
(could, likely push to 30miles, with modest pedal assist)
Compare to new eZip 24V 10Ah SLA at $140 with 7-8 mile, motor only, range

4, of 5, Floureon 7S 5000mah Lipo, all cells still within 1/100thV of each other, after setting 9 months!!!

 

[wturber]

Strange quirk is single brake lever ... for rear and front brakes. Right side rear brake pad slides forward under moderate application engaging the cable to the front brakes. ? Might work OK but will require constant monitor and frequent adjustment?

That's a SureStop brake system. I'd be curious about whether it works OK or not.

http://surestop.bike/

 

[DrkAngel]

After a fair bit of use, brakes seem to work just fine.
However, I personally am afraid to trust them.
A single cable, mount or pad failure will leave me with no brakes!

I view their system as a big step backwards ... back to the days with a single master brake cylinder on cars and trucks.
Any failure resulted in a total loss of brakes, but at least you could slow down by downshifting and the emergency-parking brake kinda worked, a bit.
Don't see the point or any reasonable advantage to this system. If I were to keep this bike, with motor, adding dual brake controls would be required.

 

[DrkAngel]

.
... BD-36 Replacement Brushes - $32

 

[dogman dan]

Nice score on the Candis. We paid about 150 for the wifes. She still loves it btw. We were not so sure about the funny rear brake on it at first, but its working fine a year later. She rides no motor, at about 10 mph max, so the brakes not an issue. Easy to add another brake handle, but we just did not need it with no motor.

Those old brushed WE motors were ok, but just don't climb a hill for 15 miles with one, in summer. My house was just too far from work, and too high up the hill for the brushed WE. They just run a bit hotter, quicker, than the brushless WE.

 

[DrkAngel]

.
... SureStop replacement brake - $19.99 + shipping ($2.05 to NY State)

for Schwinn Candis etc.
Could be used to convert any dual brake bike to single lever(?), requires additional cable housing.
Important to keep front brakes adjusted to maximize braking effectiveness and minimize SureStop pad wear.

 

[DrkAngel]

Found a Schwinn frame with proper fork, and dual brakes, so will be transferring BD-36. Makes me feel better about "proper" brakes.
As for speed with 36V battery, 23mph is inefficient unless continuous assist applied and "illegal", I just acquired a quantity of 10s2p 5.1Ah BMSed "bricks" with an interesting attribute, they have a substantial percentage of their energy between 35V and 37V! More than from 37V to 4.2V!!
Only charging to 37V and discharging to 35V will cut capacity to ~45% but will effectively limit speed to near the "legal" 20mph, increase efficiency and greatly prolong battery life. A 5 brick battery ($125 - Black Friday sale) will provide me with near 12Ah for decent range at 20mph and I can always charge to 41V for near 24Ah, for trips, or longer-faster commute.

Got 12 bricks coming today, will test to confirm capacity of cells and quality of BMS, and report.

 

[wturber]

I just acquired a quantity of 10s2p 5.1Ah BMSed "bricks" with an interesting attribute, they have a substantial percentage of their energy between 35V and 37V! More than from 37V to 4.2V!!
Only charging to 37V and discharging to 35V will cut capacity to ~45% but will effectively limit speed to near the "legal" 20mph, increase efficiency and greatly prolong battery life. A 5 brick battery ($125 - Black Friday sale) will provide me with near 10Ah for decent range at 20mph and I can always charge to 41V for near 20Ah, for trips, or longer-faster commute.

Got 12 bricks coming today, will test to confirm capacity of cells and quality of BMS, and report.

I'm starting a cargo bike build and hope to have an optional configuration with some long range batteries. The ones you have look interesting, but I'm apprehensive since they are not new cells. I look forward to seeing what you find.

 

[DrkAngel]

Got 12 bricks coming today, will test to confirm capacity of cells and quality of BMS, and report.

Got partial order today, called and was informed 10s2p bricks shipped by 3rd party, from California. (arriving "later")
Having good initial success resurrecting Ryobi "40Max" battery packs,
18V Ryobi batteries, resurrecting some cells
9s Lipo taking .1A charge (NiCd setting) but can't test cell balance till disassemble further.

 

[DrkAngel]

Got 12 bricks coming today, will test to confirm capacity of cells and quality of BMS, and report.

Got partial order today, called and was informed 10s2p bricks shipped by 3rd party, from California. (arriving "later")
Having good initial success resurrecting Ryobi "40Max" battery packs,
18V Ryobi batteries, resurrecting some cells
9s Lipo taking .1A charge (NiCd setting) but can't test cell balance till disassemble further.

EVE 10s2p 36V 5.1Ah bricks come nicely balanced @ ~ 3.60V.
Of concern is a constant LED blinking.
Charging port supplies pulses of charge from my MeanWell power supply, so altered charge to power output for nice smooth charge.
Blue LED turned constant LED as charged topped off near 42V and cells were near perfectly balanced in 2 different segments. 1 segment of 5s2p was within 1/1000V, the other was within 1/000V but ~1/100V lower than 1st segment. Very good but "different".

BMS does draw some noticeable power!
After several days, 1 battery dropped below 41V and LED began blinking again.
Guess I can't recommend using BMS, if subjecting to any prolonged storage!
Balance function seems excellent though ... might leave 1 BMS and parallel 6s more of bare cells for a 10s8p 36V 20.4Ah build.
Bricks are ideal for simple BMS removal, leaving nice connected cells for simple reassembly!

Will charge all bricks and monitor voltage drop. any with faster "drop" will be recharged, BMS removed and cells monitored for self-discharge.

Preliminary charge , from 36V to near 42V difficult to determine actual capacity but guesstimate near 100% capacity, will discharge 1 brick to 33V for a capacity charge test.

 

[DrkAngel]

Candis w/Aotema motor was stolen early this year., without battery. Just spotted it being ridden and followed to home of thief and was lucky to flag down cop within a couple minutes.

Recovered but damaged:
controller missing;
battery bag straps broken;
brakes worn down and front disconnected;
throttle wire stretched and knotted;
7spd shifter broken;
grip missing;
chain rusted.
Will need work!

Might restore Candis to original and finally relace 600w hub into a 20" for 20mph @ 36V, for some BMX.
26" seems underpowered at 23mph "gearing".
20MPH for some lightweight kid should be great fun ... or as transportable scooter for anyone?

 

[dogman dan]

Too cool you got the Candis back. They really are a nice bike, motor or no motor.

Controller and stuff to run it again won't cost near as much as another Candis.

 

[DrkAngel]

Too cool you got the Candis back. They really are a nice bike, motor or no motor.

Controller and stuff to run it again won't cost near as much as another Candis.

Rebuild with Aotema hub?

Cons:
28-14T sprockets comfortably pedals only near 20mph;
36V = 23mph is inefficient and "illegal";
(NYS eBike is finally legal, at Federal standard - 20mph 750w)
25.9V = 17mph seems too anemic; (see graph, below)

Pros:
Well, brakes worn right down, best time to replace 2in1 "Surestop braking system" with dual handle w/motor disconnect levers;
Comfortable cruising bike;
Has required wide fork;
Have spare 7spd click shifter;
Might be perfect for some lightweight?

On the other hand, Candis, seems, would be perfect for a 750/1000w rear hub kit, which includes the dual brake levers.
(500w kit preferred, but negligible cost savings!)
And relace the Aotoma into a 20" for a spunky 20mph @ 36V or a sedentary 15mph @ 25.9V, a win-win?

26" vs 20" performance graph.
volts, amps, wheel size adjusted to match actual torque, speed and watt curve.

 

[dogman dan]

Not sure what you want now. But the Candis, for a cheap bike, is worth rebuilding back to rideable. One thing I'd do is put front and back brake levers on it, rather than the one handle works both thing. But its a pretty decent frame to work from, very similar to much more expensive townies.

For sure, anything brushless will be about 30% more efficient than the old brushed aotema. Those just die quick in the climate I live in. The extra heat they make just cooks them here in the desert. But in most climates, its still a cheap motor to get running again. Controllers cost so little in brushed 36v 20 amps. But range is about 30% less than any brushless hub.

You want a real improvement, put a good 500w rated brushless geared motor such as a Mac on that Candis. Efficient, coasts great, no heavier than the aotema, and at 48v can really perform nice.

The aotema should waste less energy starting up in 20", so thats a win for sure. Cruising should still be a bit less efficient than anything brushless. The brushes just spark and make heat no matter what.

 

[DrkAngel]

I do have an eBikeling 500w geared front hub that I never got around to using.
But, more likely, I also have a spare 750\1000w rear DD. Overkill for the bike so will probably use a 36V controller-battery for "reasonable" use. Have 6x 36V 14Ah batteries.
Just ordering a "honest" 750/1500w rear hub kit for another project and got a full refund on defective cell purchase, so, shopping for cells for some 14s builds.

Aotema will shine in a 20" wheel and, pretty sure I can squeeze it onto the rear of a BMX, add foot pegs and a bench seat, should be great fun. If not fun enough ... push to 48V? 48V "simulator's" = 1000w+.

 

[dogman dan]

Yeah, push the aotema to 48v in 20". But not much farther than that. And keep duration of hard rides short enough to let it cool off.

Put the dd on the candis then, I'd say.