1. Pulled the forks. Found that they both had the corrosion in the usual spot. I cant be bothered mucking about filling and sanding so plan to replace them next year. Fitted new fork seals anyway and Gizmos springs that I've had for a while. Much better now and not leaking despite the corrosion. New seals are a lot softer than the old.
2. Removed the tire to replace with one of these http://veerubber.co.th/web/mview.php?Pname=VRM-022&Ptype=Trail%20Tires&lang=en
Tire quickly went flat because I had pinched it in 2 places despite using antipinch tire spoons.
3. Swore a lot.
4. Removed tire and patched 2 punctures and refitted.
5. Repeated the above 2, 3 but with 3 being much longer and louder.
6. Used the cable tie method of tire replacement (described on this forum) which is easy and makes pinching the tube impossible.
7. Wondered why I didn't do that in the first place.
8. Took it for a ride. Suspension great and new tire looks the part.