Quote Originally Posted by PandaCristo View Post
i heard some myth that the two rear tires need to be the same in condition ?
2 tyres on the same axle should always be the same tyre and of same condition.
That is not a myth.

As the old tire flatted out (now it becomes the spare tire), therefore, i need to change it,
no you dont, you want to change the rear that went flat and the rear that didnt, and put the "spare" back in the boot.


or change the right rear tire?
to match the rear left, yes, or change both rear's and put the temp one back in the boot.

The current tires from the previous owner is Bridgestone ecopia, but the spare tire i changed is Michelin, is this ok to keep running like this ?
no.

ever tried to do a run with two different shoes on each of your foot? say one sport shoe and one heels? you'd probably run into problems, same principle here, you dont want to spin around in the rain because your rear end has diff