A home-built electric bike is working like a champ
I’ve been putting a lot of miles in on my bike, which has also been enhancing my MPGPP. I continue to use the lead acid batteries that came with the kit because I don’t want to see them go to waste. Since they weigh practically nothing, I carry two lithium battery packs as spares for when I over-extend the lead acids. I’ll use the lithium packs full time after the lead acids give it up — the sooner, the better.
I have taken some long trips with my lithium design. I use one 36-volt battery pack at a time. When its charge drops off, I turn a switch to use the next pack in line. The beauty of this design is that you know precisely how much power you have left at the time of switching. I have also successfully charged these batteries while on a trip.
I saw three other people on electric bikes today. I pulled up to them and chatted while we rode. These things are really catching on. Unlike my home-built, theirs looked like electric bikes — with a motor and gearbox right in the middle of the frame — and were easy to spot. I think sales would be greatly improved if the local electric-bike dealer would wake up and sell something that doesn’t look like a frumpy electric bike.
One guy told me his bike didn’t even have a throttle. It somehow automatically feeds power to the drive train when it senses you need help. I don’t care for that idea. I opened my throttle after chatting with him and left him happily pedaling away. I guess his bike didn’t think he needed any more power.
I took a trip to downtown Seattle yesterday. I called the building department at 3:30 to see if a permit was ready. It was, but they closed at 4:30. I hopped on my bike and was there in 20 minutes — in rush hour. It would have taken much longer and cost about $8 more to try that in a car. On the way home I drafted off another electric bike and nine other people drafted off of us. It was great until we hit a hill and everybody else had to fall back. Coming down the hill my trailer acted like a sail and slowed me down, so I lost the electric bike in front of me, who must have been doing thirty something. I made it home in 25 minutes.
I keep my bright yellow bike trailer hooked up full time now. It cuts my range and limits my maximum speed downhill, but I have found it to be well worth it. People often assume I have a kid on board and give me extra deference. There isn’t anything I can do about it short of carrying a “No Child Onboard” sign. It also makes me a lot easier to see and I am always carrying stuff in it. The one main problem with this trailer design is its propensity to flip on its side. I would occasionally flip it on a curve or bump when my kids were younger and it’s a lot easier to flip when it’s empty.
Electric bikes aren’t perfect, but they’re getting there. For example, when I ride in heavy rain, my throttle sometimes sticks wide open — unsettling when you first turn the power on and find yourself clinging to a bike heading for a wall. I’ve also had a lot of flat tires. I know how to repair them without taking off the wheel or using any tools, but it still gets tiresome — no pun intended. I will eventually install something more puncture resistant, which will be heavier, but who cares? It’s an electric bike. I will get a little less range. The batteries charge up in less than an hour.
I also have to confess that I shorted out one of my very expensive lithium battery packs. I crossed a wire, some sparks flew, and it was all over. Damn. It won’t take a charge anymore. But, there was no fire or explosion. Hopefully I will be able to repair the pack once I open it up and see what fried.
For all of you people too lazy to ride a regular bike … David … consider getting or building one of these. You don’t have to pedal hard at all if you don’t want to race other bikers. These things are also ideal for those of you who do not want to arrive at work sweaty and have to change clothes. You can wear regular clothes and take it easy. The bike will do most of the work if you want it to.
And depending on where you live, it could be quite a bit faster, a whole lot less expensive than a car or bus, and as carbon neutral as you can get. Just don’t ride in traffic or cross in front of cars without making eye contact first. It also helps to wave at drivers before you cross in front of them, especially the ones talking on a cell phone. They rarely wave back, but at least you know they saw you when they smile or scowl.
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