i have a lt 250 r and a ltr 450 i have been practicing wheelies and i went through a stock wheelie bar and a pro armor wheelie bar on the 450 i have gotten the wheels down pretty good but i was wondering if the bars are meant to break so it does not tweak the frame or could i have my bar welded up and strengthened any thoughts ?

Factory grab bars are actually pretty weak. They can hold the weight of the quad all day long with no problem but will bend when subject to sudden impact such as a tail drag. You should be able to have your bars straightened & reinforced without too much effort.