Maintenance Schedule There are many questions that deal with routine/ preventative maintenance (including this one which is probably the most comprehensive Optimal Maintenance Schedule) but none deal with issues related specifically to mountain bikes. 

Not all of us have access to a team of mechanics who rebuild our bikes for each weekend/ race but still want to get the optimal performance out of the components on our bikes.

Performance degradation is a continual process, I'm not going to notice a marginal decrease in performance over the sort term, but over a couple of months my brakes won't feel as good, my gear changes won't be as crisp and my suspension won't ride the same. I check over my bike after each ride and lubricate, tighten and clean as required to keep it running well and safe (I will rebleed the brakes if required) but know there's stuff I can't afford/ be bothered to do each week or month.

What I would like to know is when I should be anticipate carrying out more intensive servicing such as:


Suspension - oil and seal replacement (I have been told anecdotally that it should be every 35 - 50 hours)
Brakes - rebuild
Pivots - bearing/ bushing replacement
Rear derailler - rebuild, replace bearings/ bushings
Wheels - bearing replacement


Working on a premise of waiting until there was a definite failure or significant loss of performance would mean that I wasn't getting the most out of my bike overall and may in fact lead to my bike being out of service when I want to ride it!!
I think the maintenance periods for MTB are the hardest to predict, because conditions vary greatly.  If you ride in wet, muddy conditions you'll have to replace your drivetrain and brake components far more frequently than if you ride mostly in dry conditions.

You seem to be mostly concerned about bearing systems so I'm guessing you're riding in the slop a lot..  I'd plan on rebuilding the suspension after every season (or 6 months of solid riding), replace the disc brake pads and probably drivetrain components on the same schedule, but test this assumption - use a chain wear indicator and calipers to measure chain and brake pad wear respectively.  I wouldn't worry so much about wheel bearings, derailleur and frame pivots - they'll let you know when they're shot..