Ok, I know I'm the ultimate geek but heres what I did to make a set of polars REALLY sensitive...actually I only use these tip ups for perch when it is too cold to use my tip downs. After removing the shaft, I had a machinist friend of mine turn the shaft on a lathe to reduce the diameter of the shaft, leaving about an inch of the original diameter of the shaft at the ends so the shaft doesn't wobble. This significantly reduces the friction in the tube. I also use a really expensive cryogenic grease which I liberated from the lab I work in.....It stays really slick down to liquid nitrogen temps.....but the other commercially available grease work well too. These tip ups are SUPER sensitive, and with the lightest flag setting I can sometimes get a small active fathead minnow to trip the flag...hence I end up using the stiffer flag setting on the smooth side of the t-bar. You do get a few wind flags and false flags this way, but most people are amazed at the numbers of perch these things catch. NO resistance with them taking out the line at all even for light biters