Another day … another gearbox drop.  Still, at least I managed it in an hour from start to finish this time, which is a new PB, as our Olympic athlete-types like to refer to these things. 

Well, it looks like it’s a case of mea culpa on two out of three leaks.  

The leaks on both sides at the back of the main gearbox casing are coming from underneath the top cover plate…

… and when you whip the top off, you can see that after forty miles of gearbox oil being splattered about, there’s prety much not a single bit of “gasket” that hasn’t leaked.  I suppose it’s better that it is this gasket that’s leaking though, rather than the one linking the main gearbox casing to the tailshaft housing, as changing that would require taking the whole gearbox apart which is way beyond my level … silver linings I suppose. 

The story’s the same at the front end of the gearbox casing, though this time the oil seems to have come out and down through the selector fork hole (bottom right in this pic) rather than through the front oil seal or the gasket on the release bearing guide. Someone will probably pop along in a minute and tell us it’s designed to leak that way. 

For both of these I’ll cut new gaskets, smother the mating surfaces with gasket sealant, do ’em up tight and see what happens. 

The other leak is, as I suspected, coming from the fifth gear locking plate – indeed, it would seem that there’s actually no gasket between the plate and the tailshaft housing – not sure if there’s meant to be one. Must just be an old leak.  I’ll take the plate off, assuming that won’t break anything, shove a load of sealant on it and screw it back down.