I have been running the Rotor BSA30 ceramic bottom bracket with a Rotor 3d+ crankset for about 18 months now and it is awesome.

There seems to be an assumption that the bearings in the BSA30 adaptor are tiny, but I'm not sure why they would be. The bearings do not fit inside the BB shell and so the extra spindle diameter is besides the point. The bearings are in external cups and are sited outside the threaded BB shell, so in theory they could be as big as anything, assuming clearance from the crank arm.



I run the BSA30 in my Cervelo P3 with a Quarq Riken/S975 in BB30. No problems, but take care to space it out evenly DS>NDS to maintain the correct chainline. The only problem I ever had was with positioning the cadence magnet when I received the Riken spider under warranty, it was a bit tricky. But you don't need a magnet with your P2M.

Question - why not get a native BSA power2max, do you just really like the Rotor cranks? This "stiffness" bit with BB30 is a load of old cobblers I reckon. You push the pedals, the crank turns the chain. One of the only genuine advantages I ever saw was that a "proper" BB30 crankset can have a narrower stance width or Q-factor, but that doesn't work for everyone. Besides which, the Rotor BB30 has the same Q-factor as a BSA chainset anyway. I'd just get the FSA one if I were you, unless you have a pressing need to swap it quickly into another BB30 bike without using adaptors on that one.

Cheers,
Rich.

In reality, the Q-factor is pretty constant across most road doubles (as you can point out with the 3D and 3D+) -- even though they can have a narrower Q-factor, usually they don't because that's not what the market wants. The main advantage of a true BB30 crank is that it allows for a narrower spindle which gives your heels/ankles more clearance at "3 o'clock" on the pedal stroke. The Rotor cranks have extra-long spindles so they don't have this advantage, but other BB30 cranks like SRAM Red/Force (non-Quarq) and the Cannondale SiSL do. And this advantage is only an advantage if you pedal with a significantly heels-in/duck-footed stance.

I also run a BSA30 with my Felt B12 (the last BSA threaded B-series version) with a 3d+ and it works fine. The only grip I have is my BSA30 drive side cup the threads are damaged and it is tough to get the thing in and out (luckily I don't have to do that too often and I bought it off of another Slowtwitcher so I can't complain too much as I saved quite a bit over new).

I also have a regular 3d crank that I run on my road bike with a Dura-Ace 9000 BB. I can barely (might be all in my head actually) the difference in stiffness between both cranks. I honestly only attribute what I think I feel is stiffer is the fact my 3d+ is a TT version and my 3d is has a regular spider. That solid spider for the TT version might make it feel more stiff. In reality if I was subjected to a blind test with both cranks on the same bike I probably wouldn't be able to tell the difference (I have the same type of chainrings on both just slightly different teeth counts on the small ring only).

That is indeed the dilemma: use an ordinary BSA crank in the BSA frame, or go through the hassle of using these special BSA30 bearings for a potential gain in stiffness with a BB30 crank. Of all the cranks useable for power2max, I much prefer the look of the Rotors (especially the new ones with the simple graphics) over the others. Not that looks are most important, but it is also good crankset from what I hear about it.

Based on info from Rotors site you get the impression the 3d+ is the new an improved crank, while the 3d is old but still okay-ish. However, it's like some people have said here already, there really isn't much difference in terms of stiffness. And like you said, it is probably easier to just go with the BSA crank. Also because an ultegra BSA bottom bracket costs only 20$, while rotors BSA30 is 50$.

I've had the same experience as others with the BSA30. No issues, worked great... and wouldn't think twice about using one to accommodate my 3D+ SRM on a frame with a threaded BB.

I'd go with the 3D+ if it were me, just because most everything has gone to OS BB's. Specialized has its own, BB30, BB386Evo, BBRight, etc. The 3D+ is super versatile and would fit in all of these. You can also not only retrofit it to a threaded BB, but also a BB86 frame as well. The only problems you used to run into was BB91 (Trek's BB) but I believe that's no longer an issue.

Anyway, just my opinion. Either way, Rotor makes some great products so you'll be good regardless.

I've been running the BSA30 bottom bracket for several months on my road bike. I have had no issues with it other than what was mentioned above about mounting the Quarq cadence magnet.

I made the switch because it allowed me to buy a SRAM S9xx crankset and then just switch my S975 Driveside back and forth from my BB30 Tri bike to my road bike with just one bolt. Has worked great so far.

You just need to make sure to always keep the special tool for it close by, since as also mentioned above, the OD is is larger to fit in the bearings, so it requires its own tool and I will almost 100% guarantee that if you have any issue while traveling etc, most LBS's won't have the wrench to remove/install the BB.

---

Tim Anderson
"It's the nature of the internets that you get some dweeb who knows nothing about (insert topic here) pontificates about (topic), believing that his/her opinion is worth the same as opinions from those who actually knows what's going on." --Echappist

I have an OmniRacer 30mm BSA bottom bracket, and been trying to install a set of Rotor 3D cranks....but it appears the spindle is too short. I thought the Rotors would fit.....Am I missing something here? Rotor sells an external 30mm BB....but that would present the same issue.