The frame breaking on the tls is quite common but the trick is to run the chain a little slacker than normal, around 38mm instead of the usual tension which should be around 25mm. you dont get any chain slap or notchy throttle response. Have you had any work done to the rear damper unit? if not the weight of the bike is resting on the damper and not on the spring where it should be, puting undue stress on the frame.