MaineDad 85 #1 Posted December 3, 2012 Guys: I believe that the 300 series, 400 series, and 520 use the exact same frame correct? Or is the 520 different? Thanks, Share this post Link to post Share on other sites
TT-(Moderator) 1,127 #2 Posted December 3, 2012 Lengthwise, they are the same. I believe later-model 520 frames received additional reinforcement at the tranz mount and maybe the front footrest support rod area. Share this post Link to post Share on other sites
