tyre's for a cat 2000

[stox217]

What do people think is best for racing on short grass track's as atm im getting to much grip out of the minipin's 60 x 10 one's with i think blue insert's front spring's are blue with 30wt oil with no caster/camber on the 6th hole on the shock tower ie closest one to the tyre & back is yellow spring's with 30wt on the highest hole in the shock tower and also has minipin's on the back any help would be gratefully recieved