Given weather patterns being rather volatile these days . . . last year being the wettest summer in Mongolia . . .

Most people choose to cross Mongolia when the river levels are lower, the mud/bog factor considerably lowered, etc. Snow can come in September - nearly a meter fell in mid-September 2011, but generally it'll pass in a few days.

The southern route is considerably less interesting of a ride but also considerably less challenging. The Northern Route is fantastic. But any traverse of Mongolia is going to be worthwhile.

If you came in from the North (ie, via Russia) then all of this is moot. If you do that . . . take a back road in the Altai and view some Siberian villages which look little changed since . . . Lenin. Beautiful countryside. In fall colors absolutely spectacular and as a former north American resident I've seen my share of incredible fall colors.

Unless you get lost 350-miles should be plenty. It is fun watching people "follow" their GPS info in a place with so few formal roads. You still have to route find a bit and "read" the terrain. My KTM NEVER needed it's 600km range in Mongolia, not even close though I never had to do any significant backtracking.

It'll be a great ride as long as your flexible, have a backup plan/route and don't focus top precisely on a destination.

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