Which Bottom Bracket Should I Choose & Why?

[RGJCPU]

History: Last bike I had was a 1980 Schwinn Deluxe Varsity; I put well over 1500 miles on this bike. This bike did it all: road, cyclocross, gravel grinding and curb jumping. The bike was solid and virtually indestructible… Fast forward 30+ years and now I want to get back into biking.

I want to build a carbon cyclocross bike. I have not purchased the frameset but I have zeroed in on one (http://flyxii.com/en/products/flx-fr-603.html ).

Question: Which bottom bracket should I go with, BSA English Thread 68mm or BB30 and why? I am leaning towards the BSA 68mm because common tools can be used to service this assembly.

 

[outlash]

Both BB's need specialist tools to install, and in my experience I've had to replace the square taper BB more often than a BB30 one, but I'm sure they'll be plenty along in a minute to tell you otherwise and BB30 is the devil's work.

FWIW, Sizes are a bit limited and I can't see a geometry chart to check. Cheap carbon CF on a crosser? Not for me, and TBH it's not that light either. I wouldn't buy it.

 

[Milkfloat]

BB30 is in theory lighter and stiffer as well potentially being narrower. The tools required for maintenance can be pretty cheap circa $30. However, many people have reported issues with creaking and frequent bearing replacement. I have BB30 on one of my bikes and apart from some early creaking that was remedied with some grease it has been fine.

However, good BB30 fit depends on a well built frame with very good tolerances. Looking at the frame you posted the finsihing is not too amazing, so you may have more issues than from a recognised frame supplier.

 

[lpretro1]

Stay away from BB30 - PF30 fine but not BB30 unless you want a creaking BB. TBH looking at that website that frame doesn't look very good quality at all - better off going for a known brand

 

[boydj]

The English thread 68mm would keep things simple and give more options for the selection of chainset.

 

[Venod]

I have run and serviced BB30 in a Cannondale (without special tools) but I prefer 68mm threaded for ease of maintenance and choice of BB and Chainset.

 

[fossyant]

If it will take a square taper then you might be better off as Hollowtech and BB30 require well finished and 'square' threads/bb shell. That frame looks a poorly finished, so stick with square taper if you can.