California has all sorts of bizarre DMV laws, and it still isn't a big deal here. We can get charged past registration for bikes that are disassembled and packed in boxes in a garage. But to get a title for an old, untitled bike (or car) is quite easy.
First, you go to the DMV with an "application for title" (I think it is form 137, iirc). Fill it out with the VIN, purchase price, etc. Pay the registration. They give you a 90 day temporary permit, and a form to take to the CHP for inspection. Bring the bike, car, or even just the frame and engine, and they verify the VIN. Supposedly any cop/leo can do this as well, but the CHP is convenient. You can ride it with the temporary permit, so you don't even need to tow it.
The CHP checks to see if the VIN is stolen, Salvaged, etc, and then fills out the form, which you take back to the DMV. They give you the plates, and the title comes 6 weeks later.