I use Purolator cyle oil filters on my CBR. Same one listed for all models of 600, 900, 929, 954, and RC51. I get mine from Amazon once a year for $10 a two pack. I did use a Pure One filter once, but I read they can reduce oil flow slightly. Not a concern in my truck, but at 10,000 RPM's on a bike, might make a difference.
My bike had a fram ph6607 on it when I bought it. That number crossed over to a 93 Mazda RX7. My business partner had just sold his 93 RX7, and we had 3 of them on the shelf. Denso brand, had zero problems.
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