Article can be found on page 75.

Recently, I asked a few mechanics and motorcyclists, "are all oil filters created equally?".  To my surprise, they didn't seem to know.  The reason I asked this question, was because a customer of ours came to our open house riding his motorcycle, which has an S&S, 113 inch EVO engine, and the oil was spraying out of his oil filter.  He had installed a new oil filter (OEM part #63798-99) which is effective down to about 10 microns.  A micron is defined by the size of the holes that are present in the oil filter.  According to motorcycleinfo.calsci.com, 25 microns is equal to about 1 thousandth of an inch.  The OEM part #63798-99 was designed for the '99 and up Twin Cam engine.  He should have installed OEM part #63796-77, which is effective down to about 30 microns.  The reason I knew what his problem was, is because in 1999, I was working in a Harley-Davidson Dealership and my co-workers talked me into installing the new style twin Cam oil filter on my Shovelhead, believing that the smaller micron holes would filter better.  I didn't even get out of the shop and the oil filter swelled up and blew oil out of it's seal.

In closing, the Twin Cam oil filter should never be installed on the earlier H-D engines or the high performance S&S EVO style engines.