Andy I am headset guy! Tried/trying to instal xt shifters and xt brakes for my old lx combo’s, which I will be selling at some point. Oldfart has it right. The nipple end has gone too far into the housing! It’s supposed to stop at first resistance so when the trigger is pressed tension is caused. I must have hit one of the triggers when pulling it through. Andy please give me your mates number or email, And someone else please post a story of bike DIY gone wrong, cos I’m having the weekend from hell, and need to feel better. Can’t see me riding on Monday as planned. Now I know why you pay so much for a service!!!!