Found this interesting article about factory support for vintage Suzuki motorcycles, would be neat if Yamaha had a similar program. Before anyone yells that this isn't Yamaha related, this post is in the lounge 

bikes.suzuki.co.uk/owners/team-classic-suzuki/bike-builds/

I've never seen anyone "yell" at anyone here because a post is not Yamaha related...  and in any case, this one kind of is about Yamaha parts availability.

It's not clear what Suzuki is doing or supplying...  is it only for certain classic models? 

Anyway, a big part of the success of Yamaha vintage bikes in my opinion is the exceptional parts availability...  some of this is due to Yamaha "recycling" by using the same parts on different models for decades. 

Suzuki has decent parts availability...  I have a couple of Suzuki's...  Yamaha parts, new and NOS, seem to have the best availability though?