The wheel and tyre spin beautifully when on the centre stand. Rubbing can only be due to tyre growth at speed I suspect. Lesson learnt: allow more space for tyre growth!
I don’t know why the fork oil lost viscosity, I do confess I did not change it annually, but my mileage is pathetically low, so this really shouldn’t be a reason. Fork oil is one of those things I don’t tend to put much thought into, I tend to buy whatever is on the shelf when I need it. Perhaps I used cheapo no brand stuff that just wasn’t very good? Second lesson learnt: use good brand fork oil and keep a note of what, and when, its used!
On the bright side, the rubbing must have been causing quite some drag. So sorting this out should yield a small performance boost...
And the carbon mudguard will reduce unsprung weight too...
So at least I’ve kept to my personal philosophy of always putting it back together (slightly) better than it was before!