classic motorcycle forum

Bandit; Silicone seal is soooo yesterday dude! Geoffus is right on about the oil way blocking property of silicone and Blue covers a most important point about fitting mating surfaces. Here are three products that I have great success with: No gasket - Yamaha’s, YAMABOND 4; I thin it up to 50/50 with MEK (READ THE WARNING ON THE LABEL) and paint it on. A light tap with a mallet will break parts loose easily. Mating surfaces must be completely clean, another use for that nasty MEK (seriously, this is a hazardous chemical). With a gasket – Yamabond4 on one side of the gasket and Hylomar HPF on the other side for easy off and on. The old Hylomar can be removed with MEK  (did I mention this is really nasty stuff?) new Hylomar applied and the gasket reused. For chain cases nothing I have found beats Permatex, The Right Stuff. It is everything silicone seal wants to be and more – it expands a little, stays flexible, and is truly oil resistant. Hope this helps. Digger