Fresh oil, don't overheat. I take it easy for a bit, change oil (especially if you have a liter capacity!!!) and flog it still not overheating. Heat is the enemy. You are basically micro work hardening the surfaces so heat is a killer.
Heb Dduw, heb ddim; Duw a digon
I'm that gun-totin', farm-raised, evangelical, pro-environment, OHV ridin'/drivin', Southern civil rights pro-labor Liberal yo' momma told you couldn't possibly exist.