Front or rear? According to the cross-reference at Partzilla for the 76 750-B1, it uses the same Fr rim as the 650B, 750B, 900A & 1000A. The 87-88 305 Fr is also listed in the x-ref, but I would double-check that to verify.
For the Rr only the 750B & 1000A are listed. The Rr rim is a 2.15 x 18 --- same as the 650B & I think they are all 40-spoke, but I don't know if they're interchangeable as the Rr spokes are different. I'm thinking the spoke hole angles could be different. ???
