Pursuing EV Mobility for my Cargo Bike

1426391607

It remains the primary purpose of this cargo bike project with auxiliary hub motor power to support me over local hills when I use this alternative transportation to fetch groceries at local food markets. These markets are all either just beyond a small hill like this one in this photo, or back up an equivalent hill if I ride downhill south. 

I expected from the beginning that this was a routine expectation and that this motor would do it.

Disappointment.

Twice now I have tackled this Forest Street hill with my bike prototype only to be completely surprised that it doesn't make it after all, draining my batteries, ending my pedal assisted hub motor powers. My motorized range also then comes to a complete halt after just one small hill.

I've tested this twice with a fully charged batteries. It doesn't make it without my full exertion, pedaling as hard as I can. My 48 volt battery pack becomes 42 volt in minutes and to my surprise this represents full depletion of motor power. Then I am left with all of that dead weight.

I have read in many ADs for EV bikes that a 250W hub motor bike can travel up to 20 miles on one battery charge. Experience with my 600W hub motor has shown this is not the case if there are hills. This has been confirmed now by other owners and one retailer. The manager of Batteries Plus has verified the experience.

This discovery is a set back and a great fall from expectations.

Further tests and research is continuing. Hub Motor kits called "hilltoppers" might be misleading after all . One of the major manufacturers of hub motors for bikes (selling a 250W motor) is publishing these "small print" warnings: "

  • If you live in an extremely hilly area;
  • If the combined weight of the rider and cargo exceeds 250 lbs
 These are reasons not to buy a hub motor for your bike.

1426186799

I've observed that when the hub motor is running it is creating a harmonic vibration along the mounts of the front fender. I have a deep throated musical instrument. So, I've acquired some rubber washers in the hopes of grounding this.


I visited O'Reilly's this morning and acquired a wonderfully improved fuse solution. It is wired with 12 gauge to match mine and it has an inclement weather cover. Also this fuse lights up when sprung.

1425930431

24 Hours now with my almost finished hub motor assisted cargo bike. I've been out three times now on neighborhood test rides, the longest one this morning where I attacked a few hills of various degrees of incline to find my "edges" in motor power and my new gear ratios. I thought that this is all that was needed. Many things went right.


For example, I ordered the new "department store" Schwinn bike from Amazon. This decision was based upon the motor manufacturer's requirement for a steel frame, not aluminum. I also have a front fork clearance issue, a minimum width to accommodate the motor. I visited local Walmart stores measuring similar bikes. Then I ordered a high quality metal basket from the WALD company, based on pictures only. It turns out that ALL tolerances arrived perfectly. Even the mounting screws for the cargo basket fit the Schwinn rack mount perfectly.

Presently I am intentionally driving around using up battery reserves to get an idea of my future range out and back with hills and my weight. My hand-held voltmeter is very useful.

As Spring is upon us I see the potential of long bike rides, blue skies and lots of mobile device photography and illustration.
________________

This chapter was written extemporaneous as I inquired and researched this subject. Keep reading if you want to follow my discoveries, positive and negative. My opinions are my own.
1425856856

Prototype wiring in place, batteries charged and it ALL WORKS!


Took first hub motor assisted bike ride today on my own bicycle. Smooth as silk, local streets. Flew up moderate hills, gave me mistaken impression of capacity. Kept ride simple, stayed in neighborhood. Cautious. Stayed observant.

Many more tests to perform, etc.

But all of that planning and research just paid off. Because I inherited this used motor my entire budget is still below $400. The value of the hub motor kit is about $800 so my bike is possible for about $1200. And nearly everything is new. Stay tuned for more reports.
_________________

This chapter was written extemporaneous as I inquired and researched this subject. Keep reading if you want to follow my discoveries, positive and negative. My opinions are my own.
1425832376

Rechargeable 12 volt LA batteries are now taped into pairs to be placed in the baskets on the rear of my bike. As described previously, this will lower the center of gravity and spread the weight horizontally. One benefit, the kickstand still works, whereas the previous bike arrangement caused the bike to be top heavy and it always fell onto the ground.

1425310409

The moment of truth. I've confirmed today that the new fork fits the hub motor. This photo is during this installation. Even though I did a lot of research on size (distance between forks must be at least 3 7/8") and frame materials (must be steel), when ordering parts over the internet there's no way to be sure until you do it. I got lucky.


I've also discovered that the motor axle was installed upside down for some time on the original bike, probably dangerous as the axle was only in the fork part way. No matter how much you tighten the bolts it is dangerous.

Fine tuning the fit and now ready to run wires to controller, throttle and batteries which will end up in the new baskets. This will lower the center of gravity.
____________________

This chapter was written extemporaneous as I inquired and researched this subject. Keep reading if you want to follow my discoveries, positive and negative. My opinions are my own.
1424966852

Crank and smaller front sprocket: The top photo shows the frame and crank on the bike I am remodeling. The lower photo is of another bike with a smaller single from chain sprocket, the kind I will eventually install, giving me an entire lower set of gear ratios. This photo is included here as part of my research.


2015.03.07

Progress report on this subject... Yesterday I had a slightly larger pedal crank installed. I had to stay with a one-piece crank because of the make of my bike. This gives me a greater leverage over my gears and more torque for hills.


My adjustments have also created some limitations. Sometimes my heel hits the front edge of my large cargo baskets. On occasion I also hit my toe on the front fender when turning, this is because of my larger crank making me pedal on a larger circumference. The benefits outweigh these inconveniences.

1424966651

Attention to detail. I've cleaned the acquired motor, controller and throttle. Looks like new. I've taped the wires where needed. Some of it is cracked and a portion was wearing against the frame and was bare.


Armour All for the rubber tire is next.

- 1 - - 2 - - 3 - - 4 - - 5 - - 6 - - 7 -