at how many miles should you change the timming chainng and any good how to sites

 

what year is your car? how many miles? cooper or cooper s? Are you having any issues?

 

2005 s 67k

 

On a gen1 it is a pretty rare change....
Like most cars with timing chains (as opposed to belts that last 100,000-130,000 miles) timing chains are USUALLY good for the "life" of the motor...aka, till it is rebuilt, unless oil changes have not been done, run very low, or other mechanical issues have lead to dammage....
Sure gen2 motors have issues with timing chains (with all the issues with chain elongation BMW/mini has had, it is easy IMO to understand WHY so many makers use belts), but the gen1 tri-tec has had no large scale reports of issues.... A few tensioner issues on high mile cars or after a block/head has been shaved/decked out of spec....but not much...