Well I believe my old B4 is still going strong with its new owner, that's around 20 odd years old and my Gixxer ( though a 750) will be 20 years old in March this year and has just passed it's Mot with no advisories

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Its down to plenty of preventative maintenance though, just keeping an eye on oil levels and dealing with odd noises early rather than ignoring them and waiting until the bike grinds to a halt, then it gets expensive, or worse, its off to the scrappy! Plenty of people enjoy that side of ownership, working on your own bike can make it a more personal connection to the bike, in my mind, but then I know others who prefer to let more experienced or qualified hands take the responsibility of care and repair, but generally buy newer bikes with warranties etc. to cover that.
Horses for courses as they say ;) !
The only other issue with 400's is part availability, the popular models are still usually easily catered for but some more obscure models or Grey Imports may be a bit harder to find. So as with most things these days, do your research before you commit to buy anything ;) !
Good luck and welcome back to the fold

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