Hi Dave, welcome to the forum, best place to ask questions about your bike is in sohc4 bikes section.
It's nice to have a new north westener to help swell the ranks, I'm in Warrington (in US at moment) on the Manchester side, hope you won't hold it against me
We have another Dave in Scouse land with a 400, he might know things about the 550, I've only seen inside the head just this week. From what I've seen, oiling is essential.
Sam.