The heart of Truvativ’s new front transmission is its
planetary gear mechanism. Think of it as one chainring
with all the strengths of a traditional two-ring system
and none of the weaknesses.

An early development drawing.

HammerSchmidt’s BB features a new proprietary
BB/crankset interface.
• Designed based on the legendary Howitzer BB
• Compatible with 68, 73, or 83 mm bottombracket
shell widths
• Spacers included
• AM: 15 mm crankbolt (saves weight)
• FR: 12 mm crankbolt (delivers increased stiffness)
HammerSchmidt’s Collar Assembly locks and
unlocks the sun gear, allowing rotation and
stop-rotation of the sun relative to the bike.
• Designed to mount to frames with ISCG 03
or ISCG 05 chain-guide mounting tabs*
• HammerSchmidt chain guide included
• Perpendicular axis relationship between the
collar assembly and the BB is important—this
can be tuned with a standard BB facing tool,
using both a standard BB cutter and a special
HammerSchmidt ISCG cutter

All Mountain
• Arm-length options: 170, 175
• Finish: Tungsten Gray
• Material: AL 7050 TV

Freeride
• Arm-length options: 165, 170, 175
• Finish: Galvanized Silver
• Material: AL 7050 TV (optimized
stiffness for Freeride)

The heart of Truvativ’s new front transmission is its
planetary gear mechanism. Think of it as one chainring
with all the strengths of a traditional two-ring system
and none of the weaknesses. And this magic is wrapped
up in a small, streamlined package that provides
unheard-of ground clearance.

There are two gears: 1:1 and Overdrive.

• In 1:1, everything is locked and spinning
together—in other words, turn the pedal once
and the chainring goes around once
• In Overdrive, the ratio is approximately 1:1.6;
so, turn the pedal once, and the chainring
goes around about 1.6 times
• Run 1 through 9 rear cogs: compatible with
any width bicycle chain
• 22/36 or 24/38 gear range, with a single ring!
So, how do you make this revolutionary, instant shift?
With special HammerSchmidt triggers, of course!
• Compatible with HammerSchmidt X.0 and
HammerSchmidt X.9 only
• Actuates in reverse; with a traditional front
derailleur, you pull cable to upshift—on
HammerSchmidt, you pull cable to downshift
• With only two shifting directions, you’ll never
make a bad shift