PPM of Iron in the Oil has much to do with the Micron rating of the Filter, and how many ounces of particulate the Filter will hold, before becoming fully loaded. Also, the Quality of the Filter makes a big difference, as well, and no by passing of the filter element is occurring once the filter is loaded. I know my Harley Filter is a 20 Micron Filter, but I am uncertain what the Spyder Filters are. Remember on our 998 V-Twin Spyder engines, the Owner Manuals had us changing the Oil and filter every 3,000 miles. On my 2012, I did 5-6 Oil and filter changes every 3,000 miles. Then, BRP decided we could go 4,600 miles, on Oil changes, but they increased the size of the Filter, so it would hold more particulate before loading , and not filtering the iron and particulate from the oil. Most likely, a lot of the particulate comes from the clutch discs, as well as the tranny gears. So, if iron is being checked after the Filter is plugged, then more iron in the oil after more miles, is not necessarily the oil breaking down, but the Filter plugging up . Also, using full a Synthetic Oil VS. Blends, that are lucky to contain even 10% Synthetics, also is a no brainer, for any one that has experimented using them both.
007James