Tool kit make-up is a personal process and it's a great idea for a long term traveller to home maintain the bike and work out what generally is needed and what's otherwise just bling / weight.

I think there are a few searchable threads on this forum and also http://www.horizonsunlimited.com/hubb/ which with no disrespect to xt660.com, is more focussed on your sort of tour. Asking a bloke what's in his tool roll is going to provide so many different answers but a lot of them will cross-over with common denominator answers. Pick out what's obvious and what you like the sound of (such as zip/cable ties for example), and marry that to what you actually need. Tool storage also goes down several paths including a 'tool tube' fixed to the bike or a Kriega tool roll.

Tool tube..
https://www.adventure-spec.com/defau...tool-tube.html

Kriega..
https://www.sportsbikeshop.co.uk/mot...nt_prod/207177


As for reliability, well as Steve said, they're pretty strong. The common issues that are more 'preventative maintenance' than breakdown issues are things like replacing all 5 wheel bearings as they last about the mileage your bike is at and also check / replace the headstock (steering) bearings. The swinging arm and suspension lower linkages will all need re-greasing.


How to:-
https://www.xt660.com/showthread.php...ghlight=grease

Another thing is rectifier failure which happens often due to water ingress at the plug socket. It's best to remove it (from below the radiator expansion tank - right side) and clean the contacts and then re-insulate the entire plug connection with amalgamating tape.

Tape..
https://www.screwfix.com/p/self-amal...mm-x-3m/2115v#

Thread re rectifiers and what happens when they are failing:-
https://www.xt660.com/showthread.php...ight=rectifier


Then there is the usual stuff such as ensuring your chain and sprockets, brake pads, and any other consumable are as new as possible to launch date or you'll be 4000 miles in and looking for new pads to last the next 20,000.

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