I just got a Dura Ace Crank (7710) off of Ebay and I was wondering which Dura Ace BB it is suppose to be paired with. I know it needs a Splined BB Interface and I've seen the Dura Ace 7700 and 7703. Any ideas?
(a) Dura Ace 7701 octalink road bottom bracket (aka dual chainring Dura Ace road): Nicest bearings of the bunch, and perfect on the track. Doesn't have NJS rating if that matters. Lighter than the other two. If you get it wet, it needs to be opened fairly regularly and regreased. Needle bearings on the drive side and actual adjustability in case your bottom bracket shell width is off by a millimeter or two. Great for those who don't mind working on their bike just a bit, or for track.
(b) Ultegra 6501 Octalink (aka dual-chainring Ultegra road): This is the durability winner. Good seals, steel axle, steel housing. This bottom bracket is far and away the best for typical road fixie use, and it'll outlast the frame. Easy assembly (just screw in the drive side, tighten, then screw in the non-drive side and tighten -- no adjustment per se). The seals may create slight friction, but you'll never know it in use. Find it on eBay for $25-20 brand new -- can't beat the deal.
(c) Dura Ace 7710 track bottom bracket: Heaviest of the bunch (all steel, no aluminum). Pretty much the same as the Ultegra but with the seals removed so it spins a bit easier (but frankly not much). Except for the NJS seal there's not much reason to buy this one. Why pay 2-3 times what the Ultegra costs, and get lesser performance? It's one example of where NJS means that it got approved, not that it's the best alternative out there.
Sorry, that was my mistake. There was a 6503 triple bottom bracket in Ultegra that I was indirectly warning you off on (since it wouldn't give correct chainline) and fell into the numbering system of the Dura Ace line. You are correct.