This is my 1st post, great site, I’ve just purchased a VF1000F that’s been sitting for about five years & have just been over it servicing tyres etc. we found it was only firing on the front 2 cylinders the fix was spark igniter, runs well now except for a rattle in the front top of the engine when cold, goes away when warmed up. I’m thinking a loose cam chain maybe, any ideas?