GEN I rear suspension

[big kev]

Hey guys long time no post , ive been doing a shit load of KM's with the wife on the busa of late and the rear is starting to not cope as well as it should . so ive tried searching this thread but all i get is an ERROR 404

so my question is what is a good afordable shock upgrade for the busa im looking for recomendations from guys on here that may have done an rear shock upgrade . or have they had the rear shock modified ?

thanks in advane guys