I spent last Sunday morning sketching motorcycles. There are many things I can draw "off the top of my head" and motorcycles aren't one of them. I've never really considered the anatomy of a motorcycle. These exploration sketches are not intended to be designed per se, just me experimenting with fitting forms and lines into the architecture of two-wheeled vehicles.
I used underlays to help guide the layout and structure of the motorcycles. Maybe soon, I will attempt to design a bike considering all the cool electric motorcycles making the rounds!

Update: Here is a photo of my little sketch on display in Rochester:

A colleague and I were asked to contribute to a local IDSA chapter's display booth at the Rochester Auto Show coming up this spring. This series of car sketches was an afternoon exercise done in sketchbook pro.
It is conceptually a two-seater "city car" which takes on the form of a landrover crossed with a mini.
Here are the first few attempts at drawing with sketchbook pro mobile on my ipod touch. Unfortunately, it is a first generation ipod touch and the software is a bit laggy. It is useable, but not fun :( For now, I still carry a small sketchbook :)
a few quick sketchbook pages from last month
20 minute digital sketch of an electric power generator. I recorded the process as a video, but the targeted was shifted so part is off camera. Try again!
With electric razors as the topic, a few digital sketches from friday evening exercise. A rough 10 minute page and a few manly shavers.
Series of ideation sketches from this week contemplating the T4 Rally truck (Rally RAID T1 support vehicle) Digital sketches, done in sketchbook pro.
digital sketches from winter and early spring 2009
digital sketches, warmups, etc. from Fall 2008