Interesting comparison Jacques and observations Pleiades.
I came from a 2011 GS800 to my current 2014 Tenere. Went on quite a few trips with both and although the XTZ is underpowered and almost the same weight compared to the 800 (on paper at least) the XTZ is a nicer bike to ride and especially on dirt it outshines the 800 by far. I had a few spills with the 800 off road whereas the XTZ saved me from some bad misjudgments where the 800 would have failed me. The only thing I miss from the 800 is the bit extra power and sound of the engine with the Leo Vince pipe. But the 660 with Scorpion pipes and easy wheely capabilities make it a more exciting bike to ride[emoji4]

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2014 XT660Z - Barrett pipe, DNA stage1.5, Barkbuster hand guards and handlebars, Pivot pegs, Teknik suspension, Guard-it engine protector combo, B&B rear rack, Trax topbox.