Topic debated before, assembly of front brake caliper and the lubricant to use in this assembly.
From 1970 CB 750 Honda workshop manual;- Verbatim "Note : Use silicon sealing grease (temperature range of -67~ 392 F (-55 ~ 200C). Do not use molybdenum grease known as brake grease. "
This accompanying a schematic of caliper showing the application point as both recess that accomodate active and fixed pads.
Also from Honda workshop manual 1978 CB 750 (last of SOHC bikes, with illustration of the K7 caliper in arrangement parallel to all the previous 4 cylinder motorcycle calipers;- verbatim "Install a new piston seal. Coat the piston with silicon grease and install it. Apply silicon grease to the brake pad outer circumference and install."
This, in my appreciation of it, is that Honda direct the use of this grease only in assembly of the caliper.
Anecdotal view, I've been using silicone grease in this way for some time. Part of this is that it appears to be the only common one I can use in system with mineral oil, or conventional dot fluid or silicone based fluid.
Interestingly, I dont get brake squeal in any system when using this method. It seems to offer the most competent piston return over significant period of use, being all but impervious to water ingress when exposed to poor working conditions too.
Both cycle disc (working on two four and six piston calipers) that have very concise demands in preventing drag by piston contraction when releaesd, also cars & bikes when placed on mot rollers to test, these having notably extremely low drag before brake application.
