Truvativ HammerSchmidt front transmission is launched

Posted on August 13, 2008 @ 11:12 AM

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

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