I had the same loose sprocket nut on my V92TC when I bought it this past spring. Beside using 262 (red) locktite on the nut,I also used one of the locktite retaining compounds (green - can't remember the number) on the splines between the shaft and pulley. Retaining compounds are designed to fill the space between parts such as where a bearing has wallowed out its housing. There was a fair amount of backlash from where the shaft had fretted away material from the pulley spline. My concern was that the nut only pulls the pulley onto the shaft. With increased backlash between the splines, it would be possible for alternating acceleration / deceleration to let the pulley begin to slip behind the nut - then it's back to square one again.
On a technical note, the red dust is the result of "fretting". Fretting occurs when two pieces of metal are able to move against each other while under pressure. Microscopic particles of metal are ripped from the surface and they quickly oxidize. Since the pulley is steel (iron) you are seeing tiny rust particles.
I've put about 3k miles on it since the fix and recently pulled the cover and that pulley is just a tight as new.
Good info here MH1! Got to get that number for the "green' goop.. hehe Thanks for the addition! No one likes to worry bout a loose pulley.
Looks like your about to be back up and running lawnstripper. I do hope that was the issue and that you get some weather to ride in to check it out...
2011 White Vision - Nuvi 550, Lowers, Lloydz 2nd filter, Vic perf filter, CB/Icom, 96 Brake LED's, Clear Signal lens/Switchbacks, VIC Hwy Pegs, Stebel Horn, 7Jurock 15" Shield, PCV, Lloyd ATS and Variable intake, Ness honkers
2004 V92 TC - S1 flash, level 1 slip-on, Ness big sucker K&N, ISO Grips, 4x1.5 Highway Hawg Risers, extra chrome (never too much), JM 2k CB 4' antena, Mustang seat, HD Front TS & Lowers, OD Pulley
Retired Navy SCPO