God, this guy is quite persistent
"Distance selling regulations is for disputes where the seller sells an item which is different to what was listed. You received the tyre which was listed"
Isn't that exactly the issue in the first place? It was listed with 3.5mm and 4mm thread, but it doesn't have that...
So I went back to him and said either arrange for someone to pick this up and provide a full refund or escalate it to eBay.
That's the eBay listing:
http://www.ebay.co.uk/itm/255-35-zR1...-/231105431067