Can someone tell me how long a chain is good for.

 

anywhere between 50 to 10000 miles. i'm not being a dick, that's the god's honest truth. there are SOOOooo many variables that will depreciate chain life, it's impossible to put a number on it.

change it when it needs it.

 

Yep, riding style, weather & road conditions, maintenance. Don't rely on "replace" mark on the chain adjustment either. Chains stretch & wear in different places, putting strain & wear on the spockets as well.

 

lol im on 13.3k oopies

 

hahahahah 50 miles...muahahahhaha...knight, we're talking chains here and NOT the oil you've put in your bike! hahahhahahahhahahhah....

 

Forever? If you oil and clean your chain regularly there's no reason why it wouldn't outlive any other part on your bike. But any abuse, rust, lots of wheelies will shorten the lifespan of the chain. But if a chain is starting to look ragged you need to make sure you check your sprockets for wear as well. A failing chaing will wear down the teeth of your sprockets.