Welcome to the forum. To elaborate on what CW posted, the only issue to really be aware of is that on Gen I bikes the Cam Chain Tensioner, (CCT), is known to fail around 50k miles or later. Mine failed at 83k miles, others have failed closer to 50k. One may have failed earlier than that, but there hasn't been good follow up on that case, so it's unknown if there were other things in play.
Yamaha generally accepts that you should replace the CCT before or at the second valve check. Super Tenere's have a 26k mile valve check/adjust interval. So if you decide to go with one of the really great deals on Gen I bikes, ask if the CCT has been replaced. If it hasn't, or you can't verify that it has, consider pinging your local dealer to see what that would cost. The part is less than $100, but installation cost can vary widely.
Now, if it's just a low mile bike, don't stress about it. It's not going to fail w/o warning. The cam chain starts getting noisy on the upper right side of the engine on cold starts. If it's more than 5 seconds, it's starting to become an issue. Just something to plan on dealing with when you get to the next valve check interval. Be aware that the CCT was superseded, so there is only one in the part system now and it's the latest version. There have been two updates. The same part fits all Super Tenere bikes from 2010 to 2019. No failures of the later part have been reported. Some feel it's just preventative maintenance to replace it every other valve check/adjustment. I can live with doing that every 52k miles.
Just about the only other issue for Gen I bikes that you might call an "issue" is that after around 50-60k miles or so the clutch can get a little vibey in the 3500 rpm range under load. If and when that starts to bother you with more vibration, you can swap to the Gen II clutch hub which has been re-designed, and it will be a direct swap. It's not listed as a superseded part, but it fits. You buy the clutch hub and nut for it, along with a gasket and you're out about $400 or less. Easy to do yourself if you have an impact wrench. Don't even need to dump the oil.
And again, nothing here is going to break, just some extra vibration. It's totally a matter of if it bothers you or not.
There are various specific changes between Gen I and II. The over all result is that the Gen II is smoother, but the Gen I is no dog. Find a good deal, and decide you don't need/want cruise control, go for the Gen I. Everything else can be added. For that matter, you can add a nice Rostra electronic CC to the Gen I for a very reasonable cost too.
Poke around the forum, do some searches and enjoy some reading. Can't find an answer to your questions, ask them!
