I decided to stop api.bicingwatch.com, because it was too much work for too few visitors.
I have uploaded the source code to github, where you can also find a recent dump of the data. The data covers more than one year of statistics, which might be useful for other projects.
You can find the project here: http://github.com/christofdamian/api.bicingwatch .
I might pick it up in the future again, if I find the time.