I unfortunately had to replace one of my tyres this week as I had managed to pickup a nail in a spot where it could not be patched. I ended up going to Addison Tyres in Tipton www.discounttyresuk.co.uk
The did a really good job for me but obtaining the correct tyre is not a simple and straight forward as you would think. When they searched the Continental site for the correct code 2 tyres turn up with different codes, but no explanation as to what the difference is. After an email to Continental themselves it turns out that one is a standard tyre with very little rim protection and the other is the correct Honda specific fit with the extra wide rim protection. When you compare the two tyres they are completely different.
Jason (the manager at Addison Tyres) went to a great deal of trouble to track down the correct tyre for me and passed on the details from Continental. I have attached a copy of the email (redacting the contact at Continental as I'm sure he won't want loads of people emailing and phoning him).
So If you are looking to match up the existing tyres on your FK8 on the OEM rims the type specification and product code you need is:
245/30 ZR20 90 Y XL FR Sport Contact 6 (03579010000)
While I was there the manager warned me about 20" rims being susceptible to buckling with the amount of pot holes that we have, especially at the moment. But he sowed me the 'state of the art' straightening machine that they have there and combined with a refurbishment service that they use can fix most problems. Which, being local to me is good to know if the worst happens.
The service there was really good and they went the extra mile to get me sorted. The lads there were really good and took a lot of care over my car and pride in their work, they even cleaned all the fitting soap off the tyre, so it doesn't look a mess when you leave (unlike a lot of garages that I know).
So I thought I would pass on this info, just in case you need to replace your tyres and want to be sure that you are getting the correct ones.
Hope this helps...