BBSwapFinder

index / standards / record

T47 internal (T47-85.5 / T47-86 / T47-92) bottom bracket shell (M47 x 1.0, 85.5-92 mm)

What a T47 internal (T47-85.5 / T47-86 / T47-92) shell measures, which crank spindles it hosts, and the bottom bracket to buy.

Published dimensions
Typethreaded
Shell inside diameterabout 46 mm bore, cut with an M47 x 1.0 thread
Shell width85.5 mm, 86 mm and 92 mm
ThreadM47 x 1.0 (47 mm outside thread diameter, 1.0 mm pitch), drive-side left-hand
Crank spindles it hosts24 mm (Shimano), 24/22 mm (GXP) and 28.99 mm (DUB) via the matching T47 BB; the 46 mm bore clears a 30 mm spindle
SHELL 85.5 mm, 86 mm and 92 mm
SPINDLE 24 mm (Shimano), 24/22 mm (GXP) and 28.99 mm (DUB) via the matching T47 BB; the 46 mm bore clears a 30 mm spindle

Used on: road and gravel frames using the wider T47 shell (replaces a press-fit BB86/PF86 shell).

On an 85.5 mm or wider T47 shell the bearings sit inboard of the frame, so it is called internal and uses a shorter BB than the external version. An external T47 BB will not fit a wide internal shell.

Fit a crank to this shell
SRAM DUB (28.99 mm) in a T47 internal (T47-85.5 / T47-86 / T47-92) shelldrops inT47 external (T47-68 / T47-73)related shell (M47 x 1.0, 68/73 mm)

SOURCES: White Industries, Internal T47 Bottom Bracket · Escape Collective, Threaded #12: the woes of T47 bottom brackets