Do Seahawks fans despise the 49ers as much as followers of Galatasaray Spor Kulub hate Fenerbahce Spor Kulub? We'll find out Sept. 15. That's when the 49ers visit CenturyLink Field and when the fans there hope to set a Guinness world record for the loudest crowd. The current record holders, the fans of Galatasary, a Turkish soccer team, achieved a din of 131.76 decibels during a match against rival Fenerbahce on March 18, 2011. According to The Seattle Post-Intelligencer, a Seahawks fan group called Volume12 has applied to Guinness to break the record and figures that the 49ers game will bring fans to full roar. The 49ers players, especially the offensive linemen, long have acknowledged that Seattle is their loudest and toughest venue, and they suffered the worst loss of the Jim Harbaugh era, 42-13, there on their most recent visit. In fact, the 49ers have lost seven of their last 10 contests in Seattle. The good news: The 49ers can take solace that despite all the noise from those blasted Galatasary backers in 2011, visiting Fenerbahce triumphed 2-1.