Howdy , ordered new clutch kit for my 67 A65. I'm gonna use ATF so wondering if best to pre soak them or install dry? had lotsa Hondas and always pre soaked them but not sure on the BSA. Again, thanks for the input, Wayno
I presoaked mine once and after installation the clutch slipped. I couldn't fix it so ultimately ordered another set- didn't soak, no slip.
I think much depends on the type of ATF you're going to use, modern ATF contains friction modifiers which will cause clutch slippage.
The general recommendation is to use ATF type F which is an older grade with less or no friction modifiers.
Alternately use monograde 30 oil with an API grade no higher than SG.
using 30 oil because there doesn't seem to be any 20 left in the world. Use the same stuff in my 30 plus year old Ariens mower as well. Works fine in the T100 clutch.
30 weight running in oil is also fine for clutches. It doesn’t have the level of friction modifiers in as its designed to aid cylinder bore-ring bedding in.
In my experience, installing the friction plates dry works best. The steel plates will adhere to the friction plates well when their surface is roughed up a little bit also, either by bead blasting, or scuffing on a rough surface to cut some light scratches in the steel driven plates.This will enhance adhesion, which means you won't have to pre-load the clutch springs quite as much, in turn leading to a lighter pull at the clutch lever. I also recommend using plain 20w50 oil in the primary chaincase. Be sure not to saturate the friction plates with too much oil, as they will be prone to sticking together after periods of inactivity. The oil is in the primary chaincase to lubricate the chain, and to some degree, helps in cooling the stator. I worked at a Harley dealership for a couple of years, and we always soaked the clutch plates in oil for an hour before installing, but I don't recommend it with the vintage Brit bike clutches.
Thanks to all. I had read an old topic on this subject which steered me towards the ATF/F and even 20wt fork oil ideas but 20w50 is already on my shelf. I continue to learn more and more through this site and my contacts with Dave at the Bonneville shop. Thanks Again, Wayno
Oil questions are engaging. My favourite primary oil is mineral Tractor Universal 10w/30 (for wet brakes).