I've been driving by Randy's Cycle Repair in Everett since it opened in 1985. It looks like an interesting place with lots of old motorbikes, and often the owner, out in front talking with people or working on bikes.
It's a tiny little shop - but big enough.
Randy has a book out called How To Get Your Motorcycle Up and Running - Service and Repair Manual.
I like the practical nature of this video from Randy where he explains you have to have spark, fuel and compression for a motorcycle to run.