It looks like it's running down the timing chain tensioner,which looks like it has some white instant gasket ozzing out of it from a previous encounter.
If so here's the gasket part and number
https://www.ajsutton.co.uk/product/y...ner-case?uid=0

I had a look at mine as it looked initially to me like you had an addition washer in the tensioner but looks the same.
opt_20170418_200556.jpg
http://imageshack.us/photo/my-images/924/0NPkMv.jpg

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2011 xt660z.
Yoshimura cans ,kev mod,Dna 2, Stahlkoffer panniers,Hepco Becker box,Givi crash bars,Mita e07 tyres.