External T47 Bottom Bracket

External T47 Bottom Bracket

Price range: $146.00 through $317.00

The White Industries External T47 Bottom Bracket combines precision machining with premium Enduro bearings for smooth, reliable performance. Designed for 68mm and 73mm T47 threaded frames and manufactured in Petaluma, California.

SKU: bttmbrcktexternalt47
Category:

Description

The White Industries External T47 Bottom Bracket delivers smooth performance, exceptional durability, and long-lasting reliability for today’s road, gravel, and mountain bikes. We machine, polish, engrave, and assemble every bottom bracket in our Petaluma, California facility. As a result, every bottom bracket reflects the precision craftsmanship riders have trusted from White Industries for more than 30 years.

White Industries helped develop the T47 bottom bracket standard in 2016 to solve common frame design challenges while improving serviceability. The larger threaded shell provides more room for oversized frame tubes and allows space for internally routed cables and wires. At the same time, it retains the simplicity and reliability of a threaded bottom bracket.

Every External T47 Bottom Bracket features premium Enduro bearings for smooth, efficient performance and long service life. Choose between durable Enduro stainless steel angular contact bearings or upgrade to Enduro XD-15 ceramic-hybrid radial bearings for even greater performance and corrosion resistance.

We offer three bearing sizes to ensure compatibility with a wide range of cranksets. Whether you’re running a White Industries crank or another manufacturer’s crankset, there’s an External T47 Bottom Bracket designed to fit your build.

The External T47 Bottom Bracket is designed for 68mm and 73mm wide T47 threaded bottom bracket shells. Its bearings sit outside the frame shell, providing additional spindle clearance for compatible cranksets. If your frame uses an 86mm or 92mm wide T47 shell, you’ll need one of our Internal T47 Bottom Brackets instead.

Because bottom bracket standards vary between frame and crank manufacturers, we recommend confirming your frame’s shell width and your crank spindle diameter before ordering. This ensures the correct fit and years of smooth, trouble-free performance.

Whether you’re upgrading your drivetrain or building a custom bike from the ground up, the White Industries External T47 Bottom Bracket delivers the precision, durability, and American-made quality your bike deserves.

Features

  • Precision CNC-machined in Petaluma, California
  • Designed for 68mm and 73mm T47 threaded bottom bracket shells
  • Available with Enduro stainless steel angular contact bearings
  • Optional Enduro XD-15 ceramic-hybrid radial bearings
  • Three bearing sizes available for broad crank compatibility
  • Threaded design for simple installation and reliable performance
  • Precision machine-engraved White Industries logos
  • Durable, fully serviceable construction
  • Made in the USA

Technical Documents

Looking for more detailed technical info? Visit our Technical Documents page here.

Specs

  • 47mm x 1mm threads (“T47” threads)
  • Designed to be used on 68mm or 73mm wide bottom bracket shells
    • Not compatible with 86mm or 92mm wide BB shells
  • Enduro stainless steel angular contact bearings
    • Enduro XD15 ceramic-hybrid bearings optional
  • Weight/pr (with bearings and seals)
    • 30mm: 91g
    • 29mm: 99g
    • 24mm: 104g
  • Cup widths (external section of each cup, including seal)
      • 24mm: 10.5mm
      • 29mm: 11.5mm
      • 30mm: 11.5mm
  • Thread depths
    • 24mm: 13.4mm
    • 29mm: 13.4mm
    • 30mm: 13.4mm
  • Bearings
    • 24mm: Enduro SMRA 2437 LLB or CXD MR 2437 LLB
    • 29mm: Enduro S71806/29 LLB or CXD 6806/29 LLB
    • 30mm: Enduro S71806 LLB or CXD 6806 LLB
  • Torque: 26-37 ft lbs (35-50 Nm)
  • Anodized with machine engraved logos
  • Available in black only

Compatibility

  • 47mm x 1mm threads (“T47” threads)
  • Designed to be used on 68mm or 73mm wide bottom bracket shells
    • Not compatible with 86mm or 92mm wide BB shells
  • Comes in three bearing sizes to fit:
    • 30mm White Industries MR30 series cranks as well as other brands of 30mm spindle cranks
    • 29mm SRAM DUB cranks as well as other brands of 29mm spindle cranks
    • 24mm Shimano HollowTech II road and mountain cranks as well as other brands of 24mm spindle cranks
    • Not compatible with square taper style spindles
  •  Compatible with White Industries T47 BB sleeve available separately under Cranks>Bottom Bracket Sleeves
  • Tools: see the Bottom Bracket Tool Compatibility document

How many spacers?

White Industries cranks

  • No spacers needed with White Industries R30 and G30 cranks on 68mm shells
    • 73mm shells are too wide to use with these models
  • No spacers needed with White Industries M30 and A30 cranks on 73mm shells
    • On 68mm shells, use one 2.5mm BSA cup spacer or one 2.5mm x 30mm spindle spacer on each side

For other manufacturers’ cranks it’s very hard to estimate exactly how many spacers you might need.  Most cranks these days have an adjustable bearing preload collar on them that can accommodate slightly wider/narrower “Outer Bearing Width” (OBW) than their target number, but you’ll need to check with your particular crank’s manufacturer. When in doubt, start with few spacers than you think you need so you don’t crush and destroy your bearings!

29mm SRAM DUB cranks

  • SRAM DUB 29mm spacers are not compatible with our BSA 29mm bottom bracket
    • Spacer kits available under Parts>Bottom Bracket Parts>Bottom Bracket Spindle Spacer Kits
  • Using SRAM’s charts, look at the BSA row, find your shell width, find your crank model, then see what spacers they require
  • Our cups are .5mm wider (each) than SRAM DUB cups so take this into account when estimating spacers

24mm Shimano HollowTech II cranks

  • Our cups are the same width as Shimano mountain BB cups (10.5mm each)
  • Our cups are 1mm narrower (each) than Shimano road BB cups
  • In either case you will normally not need spacers
  •  

What’s In The Box

  • Left and right threaded T47 external cups with bearings installed and two external seals
    • Seals should sit directly against the bearings, with the part numbers (molded into the seal) facing out
  • Cup or spindle spacers not included
  • Sleeve not included
    • White Industries T47 BB sleeve available separately under Cranks>Bottom Bracket Sleeves

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