Amsterdam to Dakar

[nug]

Either bike will do what you ask of it. The XTZ 750 is the better motorway bike. The BIG will do the mileage you need but it depends on how well the bike has been cared for. This goes for the XTZ as well of course. Both bikes are very reliable but I would say the BIG has the edge due its its simplicity & robust engine. Either way, these are old bikes who may have been "got at" by nut rounders. You need to do all obvious repairs & maintenance then ride it as much as you can to gain knowledge & confidence in your machine. Only then can you take on a journey of such distance with confidence.

I owned an SR43 BIG (same as in your picture) which carried me on many thousands of miles on some great trips. It never missed a beat.

Good luck with your choice

[nug]

Just look for general signs of poor maintenance. make sure the motor sounds sweet & has no scary top end rattles. They do sometimes sound a little rattly but any excessively metallic noises should be treated with caution. Check for any rumbles or knocking from the crankshaft area. Check the generator cover near the front sprocket for signs of damage & oil leaks. If the chain snaps it is this area that takes a hit & smashes the cases. Check chain & sprockets for lubrication and wear. This is often a good indicator or neglect elsewhere on a bike as its the easiest part to maintain. If the owner couldn't be arsed to look after the chain then they won't have done much else either !
Check the exhaust collector under the rear end as they rot out.
Test ride it.

Everything else is pretty easy to fix & will just be consumables like bearings etc, all of which I would replace before a journey like yours.

Let us know how it goes