Building a new bike - the seat post has the ‘wedge’ bolt.
When the bolt is placed loose, it is flush with the frame. As I tighten the bolt (<5 No) down, it starts to pop up.
Is this normal? Or, something I’m doing wrong?
Thanks
No, not normal. Have had this happen on one of my bikes, but not to that pop-up level. Basically, I did 2 different remedies. 1 was to push down very firmly on the bolt with the hex key as I was tightening it, and if that didn’t keep it down, then I would use a rubber faced mallet and tap the wedge down a few times as I slowly tightened it. Tap it just to get it flush with the top tube, but do this as you are tightening it in stages of increased torque, ie: tighten a little, tap it down, tighten some more, tap it, tighten, tap, tighten tap… eventually it will stay down as tightening torque increases and the wedge seats against the inner wall of the seattube and stops rising upwards.
Great - thanks for this information.
You might consider getting a new part. My Cervelo had a deformed riser post clamp. Dealer even thought it was the wrong part I wanted after looking at my picture, it was so bent out of shape by previous gorillas.
Point being- the part might be distorted, causing it to seat incorrectly.