I (well, my dealer) did the first oil change at about 600 miles (1,000 kilometers) and I have done every one since. I used the Mobil that Triumph initially recommended, then switched to Castrol when they changed their minds. I changed the oil every 10,000 miles (16,000 k's) as per the manual, and with 108,000 miles on it now it runs as good as ever and I never have to top up between changes. I figure that Triumph posted that information in the hand book and the manual for a reason. Those with high performance changes such as from Lush or Carpenter may need to use different oil because they now have different requirements.