Not really sure what that stuff is ... Besides the gunk don't start it with starting fluid. There is no oil in starting fluid and one day you will start it with starting fluid and all of a sudden EERRKK!!! No more running blaster.. If you need starting fluid to start it than that is saying you need to clean your carb thoroughly.. It's not that hard to do but buy you will need to pay attn. to detail a little bit.
There are quite a few threads in the carb section on how to properly clean and adjust a carb.
Also if you do have oil, air, exhaust or anything coming from the head gasket surface and or the exhaust flange than you need to fix the leak before it becomes a serious issue. You should perform a leak down test if in fact you believe there is a leak in the head gasket. An air leak and starting with starting fluid is asking for trouble.
Fix, clean and adjust the carb. Do a leakdown test, fix any leaks and ride happily..