In all seriousness, if you go off road on a 15 year old bike that you haven't rebuilt you're obviously taking some chances with mechanicals or discovering bad things about fatigue
If you take to the off road on a 15 year old bike you have rebuilt you are taking some chances with mechanicals!
However once that lovingly rebuilt retro has all gremlins ironed out, you know it is is built with simpler solidly performing kit and you know every nuance of the whole machine. Inherent reliability...
Which is actually pretty damned cool and doesn't have to be exotica, just your bike, your way
If you take to the off road on a 15 year old bike you have rebuilt you are taking some chances with mechanicals!
However once that lovingly rebuilt retro has all gremlins ironed out, you know it is is built with simpler solidly performing kit and you know every nuance of the whole machine. Inherent reliability...
Which is actually pretty damned cool and doesn't have to be exotica, just your bike, your way