Work in progress. I have taken it this far to reach something of an impasse. I think that the reason it's been sitting in my 'in progress' folder for months is that I haven't decided on how realistic I want to be. I don't think I'm managing to maintain a consistent level of realism through the entire picture, and it's only going to get worse. The cycle itself is consistent, but I'm not sure how to make the background match, and I don't have a clear mental image of how the shadows are going to work.
I am very pleased with the horsecycle though. I usually shy away from machinery, but I had a neat idea and I executed it without too much hemming and hawing. Also, I planned through how the critter moves and functions well enough, instead of skimping and drawing something pretty but fundamentally 'locked in place'. I may never draw the horsecycle again. If I do though, it will be much easier to position it as I like, because I know how the limbs fall and the gears work.