MY09 has seen a proliferation of frames with “new” bottom bracket designs:

• BB86, or PressFit Road• BB92, or PressFit MTB• Trek’s BB90 & BB95• BB30

In addition to these, we are seeing customers developing proprietary bottom bracket systems. There are two main goals behind all of these new BB designs to keep in mind:

to reduce frame weight and/or increase frame stiffness.

This document is intended to define these new standards and prescribe which standards SRAM/Truvativ will support.

MY10 Bottom Brackets Defined

Quick BB Reference Chart PressFit GXP

BB86 & BB92Spindle Diameter and Material

24mm, Steel

Heavy

Bearing Size (ODxIDxW)

37x24x8

Standard bearing size

Bearing FittingsPress Fit Cups

Lightweight design, easy install,

simple frame manufacture

BB Shell Requirements (WidthxID)

Road – 86mm / 41mm

MTB -92mm / 41mm

SRAM Support

Yes

PressFit GXP Road

Press Fit GXP Road Ceramic

PressFit GXP MTB

Press Fit GXP MTB Ceramic

PressFit GXP

Quick BB Reference Chart Trek

Spindle Diameter and Material

24mm, Steel

Heavy

Bearing Size (ODxIDxW)

37x24x8

Standard bearing size

Bearing FittingsDirect Press into BB Shell

Lightweight design, complex frame

manufacture

BB Shell Requirements (WidthxID)

Road – 90mm / 37mm

MTB -95mm / 37mm

SRAM Support

Cranks only

BB90

Quick BB Reference Chart

Spindle Diameter and Material

30mm, Alloy

Light weight and stiff

Bearing Size (ODxIDxW)

42x30x7

Larger bearing = Longer life

Bearing FittingsDirect Press into BB Shell

Lightweight design, complex frame

manufacture

BB Shell Requirements (WidthxID)

Road – 68mm / 42mm

MTB -73mm / 42mm

SRAM Support

Yes

BB 30 Bearing Assembly

BB 30 Bearing Assembly Ceramic

and

BB30 to BSA Adaptor Kit

BB30 Adaptor to BSA

Quick BB Reference Chart PressFit 30

Spindle Diameter and Material

30mm, Alloy

Light weight and stiff

Bearing Size (ODxIDxW)

42x30x7

Larger bearing = Longer life

Bearing FittingsPress Fit Cups

Lightweight design, easy install,

simple frame manufacture

BB Shell Requirements (WidthxID)

Road – 68mm / 46mm

MTB -73mm / 46mm

SRAM Support

Yes

BB 30 Press Fit

BB30 Press Fit Ceramic

Quick BB Reference Chart PressFit GXP /

BB86 BB92Trek BB30 PressFit 30

Spindle Diameter and Material

24mm, Steel

Heavy

24mm, Steel

Heavy

30mm, Alloy

Light weight and stiff

30mm, Alloy

Light weight and stiff

Bearing Size (ODxIDxW)

37x24x8

Standard bearing size

37x24x8

Standard bearing size

42x30x7

Larger bearing = Longer life

42x30x7

Larger bearing = Longer life

Bearing Fittings

Press Fit Cups

Lightweight design, easy install, simple frame manufacture

Direct Press into BB Shell

Lightweight design, complex frame manufacture

Direct Press into BB Shell

Lightweight design, complex frame manufacture

Press Fit Cups

Lightweight design, easy install, simple frame manufacture

BB Shell Requirements (WidthxID)

Road – 86mm / 41mm

MTB -92mm / 41mm

Road – 90mm / 37mm

MTB -95mm / 37mm

Road – 68mm / 42mm

MTB -73mm / 42mm

Road – 68mm / 46mm

MTB -73mm / 46mm

SRAM Support

PressFit GXP Road

Press Fit GXP Road Ceramic

PressFit GXP MTB

Press Fit GXP MTB Ceramic

Cranks only BB 30 Bearing Assembly

BB 30 Bearing Assembly Ceramic

BB30 to BSA Adaptor Kit

BB 30 Press Fit

BB30 Press Fit Ceramic