I just did a maxi that had been sitting for 20 years, it was in great shape but had almost 5k miles, i.e. it had been ridden for years then got abandoned after everything was wore out.
Just about everything was there and in good shape just wore out. I went through it all and now it's basically a new bike. Does low 40s, looks and rides like a stock bike just awesome-er. I probably would have stuck with a stock ported cylinder on this build but the stock cylinder was toast.
This is an almost complete list of what I did, probably put like 10 or so hours into this thing but like I said, it's cherry now, and I would put anyone on it and ride it anywhere.
New tires and tubes
New brake pads and sand the drums, grease pivot points.
New brake cable as needed (upgrade front to late model Tomos large gauge cable)
New throttle and starter cable as needed, grease throttle assy.
Clean and repack/grease cup and cone wheel bearings.
Clean and repack steering bearings
New plastic bushings in forks 'fork sliders' clean out old grease and re-grease
Maize's fork tube cutoff mod for more travel
New drive chain
Rebuild engine with new bearings and seals
Install 44 mm airsal kit
Matching high comp head
Port match stock 14 intake
Modify air filter to open inlet
Replace 12 Bing with 14 Bing from buy/sell
Upjet to 74 and tune
Proma gp pipe
New genuine Bosch points
NGK b6hs plug, gapped to spec
Di-electric grease all electric connection points
Remove horn circuit and ground blue-black
I think that's about it, basically tore down the whole bike and rebuilt it, but holy crap is it worth it, this thing is fantastic and I probably won't have to touch a thing on it for the next 10 years. Way better to do it all at once rather than chasing breakdowns and dumb little problems all the time