The challenge is to resolve the metal on metal contact of the effected parts. If the oil supply is inadequate, that may not be difficult to resolve. If the lubrication technology necessary to meet this challenge is impractical or not available, then this could be resolved by reducing the concentrated load across the effected areas.
I believe that prior to 2007 the lubrication properties necessary to support the primary drive’s operation were very modest. The introduction of the Cruise Drive on the touring rigs presented a number of unanticipated challenges to the boys and girls at H-D, and possibly one or two other folks. My sense is that if there was a lubricant on the market that was simply adequate in a pre 2007 machine, you wouldn’t stand a chance with it in a Cruise Drive tourer.
I hesitate to go straight to the sprocket assembly for the answer, because there are a lot of machines running around that don’t seem to experience this premature wear with either sprocket. At this point it’s tough to say if the failure that some experience, exceeds the practical lubrication technology available, or if it’s simply an issue for some vendors to play catch-up. Either way I believe that an awareness of the nature of this failure will help.
FWIW, re: attached photo taken today. 6-29-09 @ 255 miles: installed Jim’s 131 with SE comp sprocket and other peripheral goodies. Haven’t had the primary apart since then; replaced a few sets of lifters, though. I posted a photo of the sprocket sometime prior to install. I don’t recommend one lube over another, but have been using the lube recommended by SBB