I’m getting ready to sell my old S3 but I’m taking the crank so I need to pick up something as a replacement. It’s driving me crazy trying to figure out what options I have so I can hopefully find a good deal on something. It’s 68mm English BSA and I currently have external Rotor BSA bearings (30mm spindle). If I want to leave the bb I need something with a 30mm spindle. Rotor 3Df and 3D+ are too expensive. What other options are there with a 30mm spindle diameter and 90mm length at a reasonable price - FSA BB386 EVO? Or I should be able to swap in a Ult 6800 or DA 7900 bb and matching Shimano cranks, right?
Bottom Brackets are cheap. Stop worrying about the BB, replace it with an Ultegra BB, and then just put in an Ultegra 6700 crank.
Replace the bb as the other poster said. You can then find used cranks from $30 (fsa gossamer) and up. I got a new sram force over the holidays for $150 and missed out on a takeoff one that went for less than 100 on eBay. There are good deals out there if you are patient. Your best bet is probably st classifieds if you are ok with used.