hmmmmm ...i hwve to admit it very possible my lines are original ....not sure how bad they inside lines with residue leeching off....wish i had money to replwce all lines....id for sure go extra mile if i could ...truth is i was just trying to improve brakes some as i did some two up riding with my dauther being hete for visit with me.....hadnt seen her for year.....the return hole on brakes had just started being cloged up ......and i was quite proud i figure way to power clear it....it certainly isnt a complete all bases cover deal for brakes but it was rather quick ....and did it while i changed thr tire also......i need new lines in my future for sure along with new fluid.....but as stated fluid was flushed not long ago before return hole startrd acting up ....