Hi Colin. How are you getting on now? I have just remembered that when I got my Plus 4 brand new 5 years ago it had a tendency for the front end to start bobbing up and down over certain road surfaces and at certain speeds. I thought it was something I would just have to get used to but it gradually went away over the course of the first year, presumably as "things" bedded down/wore themselves in/got lubricated properly.