I’ve been operating electric bikes since 2008 after seeing Russ William’s demo his Crystalyte. I always enjoyed biking, but hadn’t been interested in regular use or long rides. The idea of the bike having an electric assist really sparked my interest. I started to do my homework.
Since I didn’t have any real starting point, I just looked for resellers of kits. The best bang for the buck I found was with an outfit based out of Kansas called Electric Rider. They have since changed locations and there website is more sophisticated than when I first found them. I shelled out the cash for the 408 Crystalyte RoadRunner and a few days later it arrived. It was a 36V 25A system and the only thing left was put it together.
I spent half a day going through removing parts from my silver Mongoose and installing the kit. The 408 is a heavy hub motor. Once I had it all installed, I went to work on hooking up my power tool battery packs. I got this inspiration from Russ’s demo. Everything was done and I powered it up. Spinning!
It was a pleasant summer afternoon in 2008 and I took a ride down to the local store. It ran sweet, cruising at 21mph. I started to head home and was tailing a car when all off a sudden the dreaded LVCO. I would soon be schooled in the ways of Low Voltage Cut Off. It’s a buzz kill. I had to huff it back to the house with conventional power.
It became clear that the power tool batteries weren’t going to cut it. I had to source something that would. Luckily, I found a reseller that had custom packs that were intended for ebikes. Batteryspace had a 10ah Li-Poly pack that was 5 times the rating of the power tool batteries. The cost was hard to swallow and I had some reservations about the potential fire hazard that Li-Poly’s pose. Again, it arrived a few days later with a smart charger and I was back in business.
This time to avoid the surprise of LVCO, I also bought a Watt’s Up watt meter that gave me a tally of my usage. I didn’t want to get a rude reminder at the bottom of the hill.
I took it out and the same performance speed was there. I was able to get up to 20 miles before I felt I needed to recharge. This was awesome! Soon, I was using it for my day to day commute and other rides around town. I recall one time riding it in the snow that winter, I must have spilled it a dozen times. The only thing not covered with snow was the hub motor.
Then came the need for speed. I was interested in the inner workings, I was constantly looking at what others were doing and trying out. I stumbled on to a demo of a modified motor that basically was a rewire. The standard wiring for the motors is a common point for all phases with each lead for each phase, this is referred to as a WYE. The demo from Doctorbass was wired with all phases in a loop, called DELTA.
By this time it was late spring 2009 and the hack had to happen. I had already bent 2 rims and that needed to be replaced again anyway. I opened up my 408 and started rewiring. Once it was done, I did a bench test. It ran like crap. Turns out that I had to switch one of the phase pairs and that did it. It was noticeably faster. I decided to take it our for a spin.
I was able to get the speed up to 27mph. Be reminded that this was run from a 36V 25A controller. I had anticipated going over 30mph in part to my assumption that the 1.7 x rule would apply. It didn’t because the energy was being used to push air out of the way. Another thing that I noticed was my phase wires were getting hot. One afternoon ride, I noticed smoke from my controller box. Not cool!
So I decided to slow the mustang down and go back to the drawing board. It was winter 2009, I started to notice a drop in my distance with each charge. It started to really degrade and I knew I had to replace the pack when it got down to 14 miles per charge. This is when I found LiFePO4 cells that were safe, but had some extra weight and size. Also, my silver Mongoose gave up the ghost that summer and I had everything now on my new Schwinn mountain bike.
I ordered the 10Ah Headway cells from a local reseller in Lacey, WA called EV Components in the spring of 2010. I think I was the last person on the planet to get there order fulfilled from EV Components, they soon went out of business. The BMS board, hookup hardware, and smart charger were ordered from Batteryspace. A few days later, it arrived. I spent an evening putting it together and charged up the pack. The pack was huge compared to the Li-Poly and it was twice as heavy. I had already replaced my seat post rack with a Tubus rack, this was solid and I still use it today. I decided on using a Pelican case for all the electronics. I sized it perfect and everything fit just right.
Once everything was in place and up and running, I noticed a real improvement. First off, my range between charges had jumped to 35 miles! Next, the cells last 5 times as long as the Li-Poly’s. So instead of 10 months of service, I was looking at 50! This was great and offset the cost, size, and weight factors.
But the weight eventually became a factor. I ended up braking so may spokes and replaced 2 more rims before I decided that the motor and battery weren’t going to work. This is when I completely revamped my setup and changed direction…