fsa gossamer bb30 crankset installation instructions

Most outboard bottom brackets for BSA threaded frames originally were designed around cranks with a 24mm spindle. These days, BSA, ISO, and English are used interchangeably to refer to what is now considered to be a standard threaded bottom bracket shell or bottom bracket. As you may recall from AASQ #1, BSA refers to the Birmingham Small Arms company which established the threading standard for threaded bottom brackets – 1.370/1.375″ x 24 TPI threads and a left hand thread on the drive side cup. BB30 specifically refers to a standard that used 68 or 73mm shells with a 42mm inner diameter meant to press 6806 bearings directly into the frame which had a 30mm internal diameter.īefore the introduction of BSA30, there really wasn’t an answer to this question. A major source of confusion lies in the name itself – all BB30 cranksets have 30mm spindles, but not all 30mm spindle cranksets are BB30. Maybe you already own a BB30 crankset, or perhaps bought the wrong one, whatever the reason, it’s a valid question. That was sent in recently, and it’s the exact opposite of our very first AASQ – how to fit a BSA crankset into a BB30 frame. Which brings us to today’s questions, “How do I get a BB30 crank in BSA bottom bracket?” Something made even more confusing with the proliferation of 30mm spindles. Regardless of how we got here, we’re now faced with question of what cranks fit which frames. While some see the opportunity to squeeze every last bit of performance out of a frame and crankset, most see it as an endlessly confusing parade of standards designed for no other purpose than confusing the consumer.

Hit the link at the bottom of the post to submit your own question!Īh, bottom bracket standards. But there are some questions you might not want to ask your local shop or riding buddies. AASQ is our weekly series where we get to the bottom of your questions – serious or otherwise. We know, there’s no such thing as a stupid question.

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Fsa gossamer bb30 crankset installation instructions