I have a Felt 3X (2015) CX Bike that has Ultegra crankset and has a FSA BB30 w/ 24mm spindle reducers bottom bracket. I took it apart to verify it was the same as on the specs and looks to be. If I am interpreting what I see correctly, the spindle is 24mm on the Ultegra so it uses the adapters to drop down from the 30mm internal race diameter of the bearings to the 24mm of the spindle. The bearings are press fit into the from with the c-ring on the inside and normal ring on the outside - additional dirt seal.
The bearings are in need of replacement. Before I do that, I wanted to check and see if there was a better solution or recommendation for replacement? Tried to look at bunch of websites and video but only got more confused. If not, will just replace bearings and reuse the adapters, easy enough, but I did see other adapters for sale for 68mm widths but was not sure if this was an “upgrade” or was to fix frames where the bearing seats may have been damaged, etc.
The way your felt is setup is fine and the way most bb30 to shimano conversions are done. I’ve also tried the wheels mfg outboard conversion. It looks a bit like a standard threaded hollowtech bb, just pressed in, with the idea that the wider bearings makes a better bb. I can’t tell the difference.
Your setup is okay, but my preference for that would be a BBIfinite module. It’s a one piece assembly that presses into your bottom bracket and then the bearings are sized for your crank (in your case, 24mm). No creaking, very little bearing drag because they’re perfectly aligned.
If you’re looking for an upgrade, I’d recommend checking out this old Friction Facts study. It used to be posted on the CeramicSpeed website but they’ve since pulled it, my guess is because a stainless steel BB beat them out. I run Hawk Racing in all my bikes so you’d probably need their BB30.24. They have great customer service as well.
To the above, thanks so much for the insights and help. Using your comments I was able to figure out a couple of options. I did take the crank off and retightened everything and the noise went away, but I do see the conversions as being a good way to go for the longer term. Thanks again for the help as saved me a bunch of time to get your experience.
In addition to the other recommendations, I 'd also suggest the Praxis Shimano -BB/PF30 conversion. This one was designed specifically for Shimano road cranks (FSA and others have slightly different spindle tolerances than Shimano, most are slightly larger).
Just an update. After going in and tightening everything back up, I rode it for a while and the creaking came back. So I went in the direction of the Wheels Mfg. outboard but was not available where I was looking so ended up with Rotor BB30-24 Bottom Bracket converter. Have to say, it was super easy to install and it has been excellent so far (super quiet and no more creaking). I did use a bearing press to seat the drive (female) side so I did not have to force anything and the non-drive (male) side just screwed on. I did not have any thread lock so I may have to go back in and do that if if starts to come loose but it seemed to fit in pretty tight.
Again, thanks to the folks that replied to this as you helped me out a bunch.
BBinfinite. Probably great for roadies but not OK in MTB conditions. I wasted $261 only to have it suck in grit and water like a sponge and destrcut after 2 short races. No bearing sealing/protection at all. Cost me time in the race turning a pepper grinder after one lap.They basically gave me the finger when I tried to get warranty help.
