How do I know what type I have ? Is the any standard size to a modern BB. I do have external BB I think. But I do not know what size it is? There BB looks to be average size but I do not know if it is oversized, appears threaded I guess. Are they serviceable or just replace the entire BB unit. I am old schooler so the older types I am good with.
I need to replace chainrings and figured BB would need new bearings or to be replaced as well.
Thanks.