Review on Optimized Shift Cable Grease from SHIMANO SIS SP41 by Jason Ortiz

I bought this to upgrade from a Shimano 5800-105 groupset to a 6800 Ultegra. Cables for Ultegra differ from 105 (new coating provides smoother shifting). I had a question about a specific housing (also internally coated) and called Shimano technical support. This cable lubricant is mentioned in Shimano's technical documents. During our conversation, I asked a Shimano technician about its use. He recommended coating the cables running inside the housing and at the ends/exits of the housing lightly, rather than on the outside of the bare cable. I route the cable housing and the cables in the handlebars. Using this lubricant on the sections of the cables where there are bends and where the cables enter and exit will especially help the cables move smoothly. If you need to run new 6800 cables, you can apply another light coating to the cables before re-running. Do not apply this lubricant to parts of the cable that are attached to the cable anchor.