Last time I heard....which was awhile ago...the tires were no longer made. They were kick a$$ tires and hooked up on anything from dusty to cold tracks.
Has anyone started making rubber again like those guys used to? Sorex had just come on the market when I stopped racing but I think GTP rubber was still better for outdoor tracks.
If anyone knows where GTP tires are still available or who may be making something like them please let me know.