So I got a few posts in other sections but I'll post this Q? Here. I'm 6'4" 280lbs and picked up a old 1977 Fuji s10-s. It's all original and in good shape. The frame is a little small so Im gonna need to get a longer setback seatpost cause those old ones a super short. Ive been searching for one but can't find anything in a 25.8. Am I sorta screwed with that size post and just have to get what I can find? Also the hubs and rims are the original suntour set up. The rims are pretty wide for a road bike and hopefully the can take a beating from me. I tend to brake spokes once in a while on my mntnbike. Is there anything I might worry about breaking on this bike? Ive already got it dripped down and plan on getting new tires, chain, grips, and seatpost.