Noiz Waves

About a month ago it occurred to me that, 1) I work for a start-up company, and 2) no one at work owns an electric vehicle. This seems to buck the stereotypical start-up company image of ultra-geeks and their battery powered transportation. After some quick googling, I found that electric bike conversion kits were quite reasonably priced…

So I accidentally bought (1x click for Pay Now and 1x click for Confirm…) a 500W kit from Ebay for $519 including postage. The kit came with everything needed for an electric bike: wheel mounted motor, batteries, controller, throttle, and misc accessories. Being an Ebay purchase (ie. cheaply made Chinese goods) my expectations of this whole thing have been fairly low. This will be a proof of concept experiment into DIY electric bikes. For all intensive purposes, this will be a prototype. It arrived by courier a couple of weeks ago.

This project needed a name, and building upon the Ubuntu naming convention, it was called Experimental Eagle Two weeks ago Eagle entered the alpha development stage, when we (me and Dad) started assembling the kit onto my bike. I’ve had my bike for about 4 or 5 years now and it’s starting to show those signs of aging (rust, mis-aligned wheels) so it suited Eagle quite well. During the assembly, we hit several issues:

1. The rear frame for holding the batteries did not fit the bike (it was meant to clamp flimsily onto the seat post…). Instead of modding this cheap frame, it was easier to buy new one.
2. The nuts that clamp the wheel onto the front fork were rubbing against the edge of the fork. This meant the nuts couldn’t be tightened sufficiently to hold the front wheel in place so it could fall out. This was remedied by modifying some of the washers that came with the wheel.

Today we fixed these issues and got the bike into a safe state for riding. I took it for a 5km ride along the coast. This marks Eagle making it to beta, woohoo! There are a couple of minor issues that need to be fixed before it moves out of beta:

1. The rear brake cable is displaced slightly by the rear frame, meaning the rear brakes don’t come on very strong.
2. The battery pack isn’t tightly held onto the frame; at the moment, the batteries are held down by the battery bag, which is velcro’ed onto the frame. Over bumps or kerbs, the battery pack tends to bounce and move around slightly, which is undesirable.

Despite taking longer than expected to install, I’m extremely happy with the outcome. After the 5km ride (about 50/50 between pedal and motor power) the batteries still showed full voltage. This should give the bike enough range to make it to work and back on a single charge. One of the goals of Eagle was to function as an every day commuter and this is looking very achievable right now. Overall, Eagle beta has been a surprising success!

The aim is to post some more detailed posts on various aspects of Eagle in the not to distant future, so stay tuned