QUOTE(Quazacolt @ Sep 16 2013, 06:57 PM)
here's the thing though, the reason for new tires in front is so that it can wear on the front, and then when you rotate it, the new tires will be in the rear.
if you put new tires in the rear, then you rotate it, you'll have an even worse condition tire at the rear.
the thing is, one should be more diligent in rotation. to keep it simple, lets assume the most straight forward front-rear switch
say a set of tyres last for 30,000km, and assume a rotation schedule of 10,000km
the first rotation will switch the more worn to the rear, by the next 10,000 all four should technically worn the same and so you dun rotate. and you go on till the next rotation and it will be time to change all four tyres anyway.
even if one decides to rotate sooner, say at 8000km.
the second rotation comes at 24,000km which will bring the worn tyres to the back and the relatively newer to the front. then press on to 30,000km and all four would again be at the same wear rate and there is no need to put two new tyres at the front.
my point is, one can and should decide to follow a laid out plan for tyre rotation if he or she is really out to maximize the life of the tyres.
people who generally change two tyres and slap them to the front are generally just being negligent about their tyres and wait till the differences become too big to actually rotate properly.
i admit i am simplifying the matter here