OK had no tire slip at all through 5 1/2 hours of track time at WGI yesterday and Mondday, which was about the only good thing I'd say about the Toyo R888. Black Boss and I spoke with the lead mechanic on a Canadian Viper ACR World Challenge team who gave us the following info;
Don't sandblast the bead surface, if anything use walnut shell media, even that makes it difficult for tire tech to get the tires to bead seat.
Clean the bead area of the tire with brake cleaner on paper towels, he mentioned a specific brand but I don't remember it
, clean the rim with it too using a red scotch brite pad.
Ask the tire tech to use isopropyl alcohol as a lubricant instead of tire soap. He said it works and leaves no residue behind.
He also balances all of his tire sets but said many teams don't because of slippage. Michelin slicks are the worst he experience, but with his methods he gets them to seat and stay in place.
It was very good talking with them, they had 3 Vipers which were very nice and very fast on track.
Steve