The only reason I ever consider doing an extended OCI is on bikes that are very difficult to change the oil. It's a 10 minute job on my BWM's, so they get a fresh drink every 5k miles, per the manual. Same for my WR426 and TTR230.....very easy....regular changes.
But on the KTM 950 Adventure.....it's a pain in the butt. That 3k recommended OCI is always stretched to 5k miles, but as I have posted in other threads, I use Rotella T3/T4 and have complete peace of mind for $11 a gallon.
I won't trash Amsoil or any other boutique oils because I know they are excellent (I've used them many times), but in my opinion, even with extended drains in motorcycles....they are still very, very expensive compared to excellent HDEO's.
And by the way, everyone better pay close attention to the size of your sump. My WR only has a 1.8 quart capacity and the TTR is 1.5 quart, so trying to do extended drains in those is absolutely foolish. My Beemers and KTM sumps are 4 quarts.
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