FWIW,
Loctite have a process for impregnating porosities in castings with a product, can't quite remember what, but it will withstand the conditions inside combustion chambers (might be better to use a ceramic coating there anyway). May well help those that tend to leak although I don't know if it has implications for welding should that sort of repair be required. I believe it can also be used to fill pinholes in the hard chrome on fork stanchions. I looked into this after getting the Ceriani stanchions straightened then rechromed. The tubes had noticeable pinholes in the surface when i picked them up. The plater claimed that chrome naturally did that.
bazzee
Loctite have a process for impregnating porosities in castings with a product, can't quite remember what, but it will withstand the conditions inside combustion chambers (might be better to use a ceramic coating there anyway). May well help those that tend to leak although I don't know if it has implications for welding should that sort of repair be required. I believe it can also be used to fill pinholes in the hard chrome on fork stanchions. I looked into this after getting the Ceriani stanchions straightened then rechromed. The tubes had noticeable pinholes in the surface when i picked them up. The plater claimed that chrome naturally did that.
bazzee