[newday777]

You can fit any combination you want. Yes the tire manufacturer says stay with matching sets. Just watch the wear and tire pressure on both tires closely. Too many riders do not do this often enough and the tires wear quickly on these heavy beasts, especially if we carry spare tires ourselves, add to that what we freight and the tires suffer. Add to that the tire itself, possibilities of manufacturing flaws (oh my!), my last set of E3s I removed at 10,000 miles. Rear was toast, cupped and to the wear bars. Front, cupped badly and about 1000 miles or less to bald in the shallow spots.

 

[newday777]

The other question is have been changing your fork oil yearly?
This is a big factor in tire wear along with rear shock age and condition, shock oil is neglected many times too.
Change the suspension oils regularly yearly and you will see a big difference in handling and your tire wear. These bikes need regular scheduled maintenance for optimal performance of all parts.