I went to get some new pads fitted and the mechanic said he couldn't get them on as the teflon ? tips to the brake pistons had warped. He suggested replacing with the steel ones used in the earlier models. This is on a 2009 xr6t with updgraded brakes - dba4000 ?....... the heat treated ones anyway slotted front rotors and standard dba slotted rotors on the rears. Don't recall the pads he got but some heavier duty than normal ones. Question is do I ; file down the originals ? replace with new teflon ones, or replace with steel ones from earlier model ? Experiences and opinions appreciated. Cheers Stu