This may or may not reduce water ingress through the shroud gaps, but, I am going to give it a go on my BSA WD B40 during the fork rebuild. The forks share much commonality within the BSA A7, A10, etc….models.
Just two simple items per fork leg; a steel washer and a felt washer.
The inside diameter of my WD B40 shroud is about 2 & 1/8 inches, the stanchion diameter just under the bottom yolk is 1 & 3/8 inches.
In my bits and pieces box, I found x2 1 inch inside diameter steel washers. I will turn the inside diameter to fit over the stanchion. The outer diameter 3/16 to a ¼ inch less than the shroud inside diameter, or maybe less depending on the thickness of felt I can obtain.
I will make a felt washer somewhat larger diameter than the steel washer and a tight fit around the stanchion, so that the felt will hang over the steel washer circumference mushroom style for want of a better word. The steel washer and felt seal, which should be thoroughly greased well, will be held in position with the fork spring against the lower yolk once totally assembled. Hopefully, when stuffed up inside the shroud, it will be sufficient to seal up the pinch bolt slot in the bottom yolk, inside the tubing wall of the shroud (below the lower yolk) and compressed enough around the stanchion. Possibly an O-ring around the stanchion as well?
Will it reduce ingress of water I wonder? Oh, and that little gap at the top of the shroud to the top yolk. I managed to get some 30 x 5 mm o-rings that should be a tight fit around; I think 33 mm, top of the shroud. Maybe someone could suggest a better material than felt? Maybe rubber?
All the best to all….
