Carrying on preparation and parts finding for the glacial rebuild of my 1956/57 Dommy 99 I am looking at the inner chaincase to crankcase and engine plate fixings.
The hole in the crank-case behind the crank is a plain open hole of approx. 3/8" diameter.
I assume that this was originally a blind-ended hole tapped 3/8 Whitworth to take a set screw? What length was this, as a PO seems to have fitted an overlong one and broken through with it? I don't have an inner chaincase available at the moment to offer to it and the parts list is useless as it just calls for a 'pin'.
I was thinking of making a stepped stud and loctiting it in but I need a length for it.
Otherwise was it a hexagon standoff spacer above and bent metal bracket to the gearbox stud below as on the alternator bikes?
Thanks a lot.
Attachment might help a little.
I don't think it will matter if the original bolt has broken through the crankcase side as some goo on the bolt thread will help to seal this.
There is a lot of spare metal in this area so going up a thread size, if necessary, should not be a problem. Possibly even a helicoil fix. Not quite so generous with regard to the inner chaincase.