cheers Hondar...yeah it would depend on who fabricated them...metinks the pipe wall thickness is ok...it is more the quality of workmanship in this case...not the materials...an inexperienced or incompetant fabricater is the most likely scenario...no matter....they'll be TIG'd up in a couple of weeks ..the cracks are not big..only about 0.1mm wide...if that...I know the torque twist of the motor under load an reving on d-changes has caused this.....it could be avoided by incorporating a brace maybe just before the collector I reckon...keep the primarys load free

Quote Originally Posted by hondar
i feel for you mate. when u write this.. it reminds of the WTB quick header guide that i write on this thread

http://www.ozhonda.com/forum/newrepl...reply&p=184428

i have mentioned how header can cracked under extreme condition (point 2) and it must be frustrating for you.

mate,
i am not saying budget headers = bad headers, but what happen is usually the quality can be quite varies from one header to another from the same brand. maybe you are just unfortunate to pick the bad one..