I purchased one of these new on ebay from a foreign supplier and had continuing problems with it from day one. At first it stuck when I did the seat clamp up (5Nm). I contacted the supplier and they suggested stripping it and increasing the spring pre load. I did this and had to remove a jammed piece of plastic whilst I was in there. Unfortunately it then started sticking on the first ride, after another strip down it was returned to the seller and another one sent out. THIS WAS EXACTLLY THE SAME. I emailed photos and videos to the supplier and eventually returned the second post. At this point the seller refused to refund or replace the part because they were unhappy that I’d given the product negative feed back. So far I’m out the price of the post and two lots of carriage charges and don’t even have the dam post! These are very poor quality supplied by a dishonest company that hides behind ebay.