Join Date: Aug 2016
Location: Melbourne, Australia
The hole is for the overflow from your coolant pump. It directs any coolant to the outside of the engine instead of contaminating the engine oil.
If the bike is fairly new and a little crust forms, wash it off. If it persists, there is a leaking coolant pump seal.
I don't know what the sponge material is. There should be no material in that hole. If it is a blue/green colour, it may be the coolant that has crystalized.
Past: 1955 Norton ES-2, 1972 Norton 750 Commando Long Range Fastback, 1977 Honda 350XLE, 2001 R1150RT (written off), 2005 R1150RT, 2004 R1150GS, 2001 F650GS.
Current: 2013 R1200GS LC
Last edited by Houdini; 17-May-2017 at 09:23 PM (099).