Marin Bear Valley 1991 Seattube Dia?

[Inigo Montoya]

anyone knows the seattube diameter for a 1991 marin bear valley? got them frame here and caliper says its ~26,2mm but that sound strange.
looked in sheldons seatpost database but no luck. anyone here who owns a 1991 marin with similar tubing please look up seattube dia and tell me. pleeeeeeeeeeeeeeeease

 

[hamster]

I've got a 1990 Palisades, and it's a 26.2 - I think it was the same tube set.