Basic Maintenance
 

How often should I clean a lube my mountain bike?

Depends on how often you ride, and how far. Generally, you should lightly clean the bike after every ride, and give it a full clean as needed. As for the chain, well... you might have just started a flame war. We'll see. hahaha

A lot depends on how and where you ride, but assuming that you're riding single track with your friends and that you're getting dirt and grit on the bike, then you'll need to inspect it and give it a wipe down after each ride. Pay particular attention to the shifting and braking, and make certain that they (the mechanisms) are well tuned and free of crud. If the chain is gritty, it will wear faster. Inspect, lube and wipe.

Also, if you have rim brakes, then you'll have to keep on top of the wheel true. If disc, not so much.

Don't direct pressurized water toward any bearings, but you probably know that.

My brother-in-law cleans and re-lubes his chain every 100 miles. I do mine just every so often. Speaking of which, the chains on both my bikes likely need cleaned and re-lubed.

let us see the bike

^^this^^

I was talking to an employee at Performance Bike and he said not to add degreaser to the cogs or chain after every bike ride; but every so often because it strips away something I forget what.

grease.

Noise is your best indicator the chain needs cleaning/replacement.

A properly adjusted and lubed chain should be almost silent.

Right now its pretty muddied, should I worry how long I let my bicycle sit with the dirt on it?

I don't have a set schedule for doing anything anymore.

Every time that I ride I make a mental list of maintenance or adjustments that I want to do before my next ride. I'm pretty in tune to chain and derailleur noises and things like that. That's pretty much all I do. I don't even top up my tires before every ride anymore.

It is not only the dirt, which contains grit that will wear the chain and gears/cogs, it is the water that will damage the steel in the chain.

So rinsing it off and drying after a ride is a good idea.

If it has physical chunks of mud stuck to the chain, you might want to be lubing it after the rinse as well.