Hey watch it! My arse is fairly wide too, but I've managed this many years on a stock seat for my 85. It's true I don't generally go more than 200 miles from home in any one ride though. I did manage over 770 miles in three days in and around Sturgis year before last and didn't have to complain about the behind even once.
I will alternate between the rider pegs back to the passenger pegs from time to time if I get a bit restless too. (My wife has her own bike)
Not to say anything's wrong with aftermarket, and especially anything aftermarket made/sold by Sean, :worthy: but maybe try the OEM seat Mother Yamaha gave you before you go further???????/
:clapping: