Cobaltos were lighter but . . .
. . . I hope to God they were better than Deltas cos they were pretty poor brakes, in both senses i.e v pretty & v poor. I ran them after dual-pivots were introduced & had scary experience in a very wet race where everyone could stop much more quickly than me! Figured that people must have been better at cornering pre dual pivot simply because slowing down wasn't an option. Do still miss my record deltas tho/