Yamaha 2000 xl1200 /Carb issues, Hole in piston,Burning up starter relays

Had carbs rebuilt and all bad since, Now we have hole in #1 piston and keep burning up starter relays, and wont run under load in water no longer than 2 min. then burns up relay I have ,Roasted 3 relays. Mechanic set pop off pressure at 82 psi with a 1.2 seat I have been told. Can anyone tell me what the stock pop off should be?Stock Yamaha 2000 xl1200 only has D plate and chip for it. I think it may be Pop off being to high that burned hole in piston but don't know.Could anyone help