Do you know from which side you'll be starting ?
If you start from the Sunol side (some call it the "clockwise" direction*) and head southward, the climb is long and gradual, with a descent that can be a bit steep in parts.
Here's my account of the very first time I went up Calaveras from the Sunol side:
http://forums.teamestrogen.com/showt...veras#post7489
If you go up in the other direction, starting from Milpitas (aka the counterclockwise direction*), the climb is steeper but there's less distance to climb. The climb in that direction includes about a one-half mile section call "The Wall" where the gradient is about 10-12%. It can be a stinker, but once you're up over that, there's a bit of shallow up-and-down rollers to the summit, and then a nice long not too steep descent into Sunol.
(* it's called clockwise vs counterclockwise because some rides do it in a 40-ish mile loop including Niles Canyon Blvd going thru Fremont).
If you run a search on Calaveras you'll see others' impressions as well.
- Jo.