Since I dry fit my tires I found I'm going to have to use 2 inch tires, the 2.3 inch that are on those rims are giving me less than a millimeter of clearance between the chain stays.

i had designed my frame for 25mm tyres, as it is a track bike, but ended up having to use 23mm ones. they work fine, but yes, the seatstay bamboo diameter is something to consider. i think i can make them thinner using the iron bamboo, as it is really stiff.