(english) part # GEN.0000000001722 Rev.
SRAM LLC Warranty Extent of Limited Warranty SRAM warrants its products to be free from defects in materials or workmanship for a period of two years after original purchase. This warranty only applies to the original owner and is not transferable. Claims under this warranty must be made through the retailer where the bicycle or the SRAM component was purchased. Original proof of purchase is required. Local law This warranty statement gives the customer specific legal rights.
2010 Technical Manual © SRAM LLC • 2010 TRUVATIV TECHNICAL MANUAL 3
Table of Contents road chainring compatibility chart....................................................................................................................................................................................... 6 MTB Handlebars and Stems.......................................................................................................................................................................................................... 7 Pressfit gxp bottom bracket and crankset.....
SAFETY FIRST At SRAM Corporation, we care about you. Please, always wear your safety glasses and gloves when servicing your Truvativ products.
road chainring compatibility chart Combination 39-53 39-53 * 39-53 39-53 39-53 42-54 42-55 39-48 39-48 34-48 34-48 36-50 36-50 36-50 34-50 34-50 34-50 36-52 38-52 38-46 30-39-50 30-39-52 30-42-52 30-42-52 30-42-52 Rings 39 53 39 53 39 53 39 Material Steel Steel Steel AL-7075-4mm AL-7075-3mm AL-7075-4mm AL-7075-3mm 53 AL-7075-4mm 39 AL-7075-3mm 53-TT AL-7075-4mm 42 AL-7075-3mm 54-TT AL-7075-4mm 42 AL-7075-3mm 55-TT AL-7075-4mm 39 48 39 48 34-110BCD 48-110BCD 34-110BCD 48-110BCD 36-110BCD
MTB Handlebars and Stems 2 i d e n t i f y p ar t s a n d T o o ls STEM Parts* A - Steerer Clamp or direct mount bolt(s) B - Face Clamp bolts Tools Needed Safety Glasses 4, 5, and 6 mm hex wrenches Torque wrench Friction paste A B C - Stem D - Face Clamp Grease or titanium anti-seize for titanium bolts Isopropyl alcohol 400 grit sandpaper 28-tooth blade saw *Your Truvativ stem may differ from the model shown p re p are p ar t s C 1 D Use isopropyl alcohol to clean the fork steerer tube, stem steer
MTB Handlebars and Stems 4 4 Size your handlebar. If necessary, your handlebar width can be cut narrower to suit your personal preference. remove handlebar bar plugs prior to cutting. Do not cut narrower than the cut down lines specified on the handlebar. important: Standard handlebar: use the cut down lines to determine your final handlebar width then cut at the same mark on each side of the handlebar.
MTB Handlebars and Stems 8 Install handlebar controls according to manufacturer’s instructions. ADVICE Avoid scratching or gouging the handlebar when installing controls. Remove any burrs from the control clamp surfaces and smooth with 400 grit sandpaper. We highly recommend the use of friction paste when installing controls on a carbon handlebar. Coat each contact surface of the handlebar and controls with a moderate amount of friction paste prior to installing.
Pressfit gxp bottom bracket and crankset 1 anatomy 1. Non-Drive Side Crank Arm 6. Drive Side Bearing Shield 2. Non-Drive Side Bearing Shield 7. Drive Side Bottom Bracket Cup 3. Non-Drive Side Bottom Bracket Cup 8. Wave Washer 4. Bottom Bracket Shell 9. Drive Side Crank Arm and Spindle 5.
Pressfit gxp bottom bracket and crankset 5 5 Install the wave washer and then the drive side bearing shield onto the spindle, making sure the bearing shield is oriented correctly. The stepped lip on the bearing shield should face the bottom bracket shell. Advice The drive side bearing shield inner diameter has a circular design. The non-drive side bearing shield inner diameter has a “flower” like design.
Giga x pipe bottom brackets and cranksets compatibility Cranket Model Track / Single Speed Omnium Double Elita*, Rouleur, Rouleur OCT, Rouleur Carbon, Noir Road Triple Firex, Stylo, Stylo OCT, Noir XC Triple / Double with Rockguard / Single Speed Chainline Frame Shell Width Spacer Configuration 41.0 mm 68 mm - 41.2 mm 70 mm (Italian) - 44.5 mm 68 mm - 44.7 mm 70 mm (Italian) - 46.5 mm 68 mm - 46.7 mm 51.
Giga x pipe bottom brackets and cranksets 4 4 GREAS E If it is not already assembled, prepare the self-extracting crank bolt as illustrated. Apply grease to the surfaces indicated. Use a 16 mm hex (5/8”) (10 mm hex for Elita cranksets) to install self-extracting crank bolt and torque to 12–15 N•m (106–133 in-lb).
Giga x pipe bottom brackets and cranksets 8 9 p e d al i n s t alla t i o n 9 Grease the pedal threads and install pedals to the crankarms. Torque to 31–34 N•m (274–301 in-lb). Use the included pedal washers (a, Figure 9) if the pedal contact surface is not flat and smooth. important : drive side is right hand pedal-thread. Non-drive side is left hand pedal-thread.
Giga pipe / isis drive / isis overdrive bottom brackets © SRAM LLC • 2010 TRUVATIV TECHNICAL MANUAL 15
Giga pipe / isis drive / isis overdrive bottom brackets © SRAM LLC • 2010 TRUVATIV TECHNICAL MANUAL 16
Square XR / Square le / power spline bottom brackets © SRAM LLC • 2010 TRUVATIV TECHNICAL MANUAL 17
Square XR / Square le / power spline bottom brackets © SRAM LLC • 2010 TRUVATIV TECHNICAL MANUAL 18
boxguide / shiftguide / chain tensioner © SRAM LLC • 2010 TRUVATIV TECHNICAL MANUAL 19
boxguide / shiftguide / chain tensioner © SRAM LLC • 2010 TRUVATIV TECHNICAL MANUAL 20
hammerschmidt anatomy Note: The information at the beginning of this document is pulled from the user manual. Some of the user manual information will be referenced in the technical service section. introduction Your days of front shifting as you know it are over. Welcome to instant front transmission. Welcome to HammerSchmidt! HammerSchmidt is a front transmission so fast and so seamless it’s magical. It gives you the security of a single chainring, with the gear range of a double.
hammerschmidt Par t s a n d T o o ls n ee d e d • • • • • • • Safety glasses HammerSchmidt frame compatibility checker 2, 2.
frame preparation f rame p re p ara t i o n Im p o r t a n t : The following sections on Frame Preparation call for making permanent and non-reversible modifications to your frame, requiring advanced mechanical knowledge, skills, and tools. We recommend these procedures only be performed by a qualified bicycle mechanic. If you choose to perform these procedures yourself you should read and understand these instructions and have a working knowledge of tools required prior to starting work on your frame.
frame preparation f rame p re p ara t i o n - p ar t 2 Ok, are you ready for the final and most critical step in frame preparation? Step 3: Replace the bottom bracket facing cutter on your tool with the Truvativ ISCG tab facing cutter that is appropriate for your size ISCG tabs and remove all spacers from the cutter. Flush • If your ISCG tabs are flush with the face of the bottom bracket shell (zero offset), you will only be facing the tabs to ensure they are parallel to the bottom bracket shell face.
installation i n s t all h ammersc h m i d t b o t t o m b rac k e t 1 If you have a 68 mm bottom bracket shell, separate the two parts of the bottom bracket and install the included bottom bracket spacers, one over the drive side bottom bracket cup, the other over the non-drive side bottom bracket up. This will set the bottom bracket spacing to accommodate HammerSchmidt. 1 spacer spacer 2 Apply a liberal amount of grease to the bottom bracket shell threads in the frame.
installation The HammerSchmidt bottom bracket needs to be installed in a specific order: 3 A. Thread the drive side bottom bracket assembly into your frame using the Truvativ ISIS (or equivalent) bottom bracket installation tool. The drive side assembly is left-hand threaded, so turn it counter-clockwise to install and torque to 34-41 N·m (301-363 in-lb). 3 B. (not pictured) Install the non-drive side bottom bracket assembly using the Truvativ GXP (or equivalent) bottom bracket installation tool.
installation 7 The collar assembly must sit flush with the bottom bracket shell face (or spacer for 68 mm bottom brackets). So now you need to determine if you need to add ISCG tab spacers. 7 If your frame’s ISCG tabs are flush with the bottom bracket shell face, you do not need to add any spacers.
installation 9 You can check for proper collar assembly installation by sliding the anchor bolt on the collar assembly back and forth in the seal disk window. You should see the pawls in the collar assembly extend to ‘catch’ and retract to ‘release’; there should be no binding of the actuator. If you removed the rubber seal from the front of the collar assembly, slide the anchor bolt so the pawls are retracted, and re-install the rubber seal, lip side down.
installation d r i v e mec h a n i sm a n d cra n k arm i n s t alla t i o n 11 Press the large shifter paddle to pull the actuator and retract the pawls on the collar assembly. Apply grease to the drive side bottom bracket splines and crank bolt threads. Use an 8 mm hex to install the drive side crank arm assembly, making sure the spindle splines engage with the bottom bracket. Tighten the crank bolt until it stops, and torque to 48-54 N·m (425-478 in-lb).
use / maintenance h ammersc h m i d t u se 14 HammerSchmidt has two front transmission gears: 1:1 and Overdrive. In 1:1, everything in the mechanism is locked and spinning together; one turn of the pedals equals one revolution of the chainring. This is great for tackling steep climbs! In Overdrive, one turn of the pedals equals approximately 1.6 revolutions of the chainring.
technical service / anatomy E x p l o d e d v i ew o f Hammer S c h m i d t M ec h a n i sm Exploded view of Mechanism Assembly 18 17 8 9 16 15 14 13 12 11 10 Exploded view of Collar Plate Assembly 5 7 6 1 2 1 Bash Guard Nuts 2 Bash Guard 3 Planet Nuts 4 Crank Arm 5 Carrier Seal 6 Planet posts 7 Carrier Assembly 8 Planets 9 Planet Retaining Rings 10 Sun Gear 11 Ring Spacer 12 Damper 13 Bearing Assembly 14 Bearing Seal 15 Sun Retainer 16 Chainring 17 Guide Ring 18 Retaining Ring for Guide Ring 33
service schedule / torque values S er v i ce i n t er v al sc h e d u le To maintain optimal performance and durability of the HammerSchmidt, periodic maintenance is required. If you ride in extreme conditions, maintenance should be performed more frequently. Im p o r t a n t : We recommend that you have your Truvativ HammerSchmidt serviced by a qualified bicycle mechanic.
troubleshooting Tr o u b les h o o t i n g If performance issues arise, please consult the following table for possible solutions. For more information, please contact your local dealer or SRAM Dealer Service. Issue Possible Cause Cure Stuck in Overdrive/Loss of 1:1 Gear Too little tension in shift cable Adjust the shifter by turning barrel adjuster on the shifter counterclockwise.
troubleshooting Issue Possible Cause Erratic Shifting Too little tension in shift cable Cure Adjust the shifter by turning barrel adjuster on the shifter counterclockwise. If barrel adjuster will not provide sufficient adjustment, reattach cable at the cable anchor bolt per “Shifter Installation Instructions”. Too much tension in shift cable Adjust the shifter by turning barrel adjuster on the shifter clockwise.
technical service M ec h a n i sm A ssem b l y a n d Dr i v e S i d e C ra n k A rm S er v i ce W ar n i n g : Always wear your safety glasses and gloves when servicing the HammerSchmidt. Some parts of the HammerSchmidt are spring loaded and can pop out suddenly which could lead to injury if your eyes are not properly protected. Make sure you have a clean work area, clean rags, and the necessary parts and tools to service your HammerSchmidt.
technical service C h a i n r i n g R em o v al 3 Using a flathead screwdriver gently pry the retaining ring off the ring guide. Remove the guide ring and chainring. 3 Bas h G u ar d R em o v al 4 Using a 6 mm hex wrench, loosen and remove the four bash guard nuts. Remove the bash guard.
technical service C ra n k A rm R em o v al 5 Using a 5 mm hex wrench, loosen and remove the four planet nuts. Lift and remove the crank arm. 5 Hammer S c h m i d t M ec h a n i sm D i sassem b l y 6 Clamp the bearing removal tool base into a vice. Place the HammerSchmidt mechanism assembly on the tool base so the tool pins engage the recesses on the HammerSchmidt mechanism. 6 7 Place the tool clamp over the planet posts.
technical service 9 The HammerSchmidt mechanism assembly is left hand threaded. Use a 24 mm wrench and turn the clamp clockwise until the mechanism breaks free. It could take significant force to open the system. 9 10 Using a 5 mm hex wrench, remove the shoulder screw and the planet nuts. Remove the clamp tool. 10 Planet Removal Note: HammerSchmidt planet retaining rings are not reusable. Do not continue disassembly without new rings to reassemble the HammerSchmidt.
technical service Bearing Seal Removal 13 Use a small flathead screwdriver to remove the bearing seal by gently prying upward from the inner edge of the seal. Perform this step carefully to avoid bending or damaging the seal. If the seal is damaged during removal, it should be replaced to avoid creating increased drag and poor sealing performance. 13 Ring Spacer and Damper Removal Note: It is not necessary to remove the ring spacer and damper to service the HammerSchmidt mechanism assembly.
technical service C lea n M ec h a n i sm A ssem b l y Thoroughly clean any contamination and grease from the components of the mechanism assembly. Ensure that any grease residue is removed from the pawls, pawl seats, gear teeth, and the outer bearing and ensure these components are dry prior to applying fresh grease. Grease a n d R eassem b le M ec h a n i sm A ssem b l y Im p o r t a n t : Use only the grease provided in the HammerSchmidt grease kit inside the mechanism assembly.
technical service R eassem b le Bear i n g A ssem b l y 20 Apply a thin bead of grease in the space between the bearing and the outer race. 20 21 Replace the bearing seal by placing it over the bearing and pressing it firmly into the groove on the outer race. A screwdriver may be required to push the last portion of the bearing seal into the groove. 21 Ring Spacer and Damper Assembly 22 If the ring spacer and damper were removed in disassembly, they should be reassembled now.
technical service 24 Apply grease to the inside of the bearing. Make sure you fill all of the gaps with grease. Spin the bearing to evenly distribute the grease. 24 25 Thoroughly grease ring gear teeth and 1:1 pawl teeth. 25 L u b r i ca t e S u n Gear A ssem b l y 26 Apply grease to pawls, pawl seats, and spring groove of the sun gear. 26 27 Apply grease to the gear teeth and pawl teeth on the inside of the sun gear.
technical service R eassem b le M ec h a n i sm A ssem b l y 28 Place the sun gear assembly inside the ring gear. Rotate the sun assembly counter-clockwise inside the ring to allow the 1:1 pawls to mesh with the corresponding pawl teeth. 28 29 Apply grease to the sun retainer groove. 29 30 Hold the sun firmly against the ring and flip the assembly over. Using a flathead screwdriver, reinstall the sun retaining ring by pushing it into the groove on the sun assembly.
technical service 32 Place the bearing assembly on top of the carrier assembly. Wiggle them together until the bearing assembly slides slightly into the carrier assembly. Turn the ring gear counter-clockwise to ensure the gears mesh properly. Continue to turn the bearing assembly counter-clockwise until it is fully hand threaded into the carrier assembly. 32 33 Place mechanism assembly on the base of the bearing removal tool so the tool pins fit into the recesses on the outer race.
technical service C h a i n r i n g I n s t alla t i o n 36 Apply a small dab of grease to the splines and retaining ring groove of the ring gear. Using a grease brush or your finger, spread the grease all the way around the edge. 36 37 Slide the chainring and guide ring into position. 37 38 Using a flathead screwdriver, install the chainring retaining ring. Make sure that it is fully seated in the groove of the ring gear by rotating it a couple of revolutions.
technical service Bas h G u ar d I n s t alla t i o n 41 To replace the bash guard place it over the planet nuts. Using a 5 mm hex wrench, tighten the bash guard bolts. Torque to 4.5 N·m (40 in-lb). 41 reassem b le t h e mec h a n i sm A ssem b l y a n d Dr i v e s i d e C ra n k arm For reassembly of the mechanism assembly and drive side crank arm follow the instructions as shown under headings “Drive Mechanism and Crank Arm Installation” in the Installation section of this manual.
technical service C o llar Pla t e A ssem b l y S er v i ce Parts and tools needed for service: • Safety glasses • Gloves • 2, 2.5, and 4 mm hex wrenches • Clean rags • Pick • HammerSchmidt grease kit* • Small grease brush (optional) * You must use the grease supplied in the HammerSchmidt grease kit unless otherwise specified. Using any other grease will void your warranty. R em o v e t h e C o llar Pla t e A ssem b l y 1 Shift the HammerSchmidt into overdrive by pressing the small shifter paddle.
technical service C o llar Pla t e D i sassem b l y Chain Guide Removal 4 If your chain guide is damaged and needs to be replaced, locate the two screws that attach the chain guide to the collar plate and note their position. You will want to reinstall the chain guide in the same position later. Using a 2.5 mm hex wrench, remove the screws and chain guide. 4 Cable Stop Removal 5 If your cable stop is damaged and needs to be replaced, use a 2 mm hex wrench to remove the screws and cable stop.
technical service Seal Disk Removal 8 Using a 4 mm hex wrench, remove the cable stop bolt and cable stop washer. 8 9 Using a 2 mm hex wrench, remove the disk bolt. 9 10 Lift and remove the seal disk. 10 Wiper Seal Removal 11 With the seal disk removed the wiper seal can removed.
technical service Actuator Removal Note: Be sure to wear your safety glasses for this step. The actuator spring is pre-loaded and may pop out suddenly. 12 Remove the actuator spring by pinching the curved tips together and lifting the spring out of the assembly. Remove the actuator. 12 Crank Stop Removal 13 Locate the beveled edge of the crank stop retainer. Using a pick, start at the beveled edge to lift the crank stop retainer from its groove.
technical service C lea n C o llar Pla t e A ssem b l y Thoroughly clean any contamination and grease from the components of the collar plate assembly. Ensure that any grease residue is removed from the pawls, pawl seats, actuator, and the actuator recess in the collar plate and ensure these components are dry prior to applying fresh grease. Grease a n d R eassem b le C o llar Pla t e Im p o r t a n t : Use only the grease provided in the HammerSchmidt grease kit inside the collar plate assembly.
technical service 16 Insert the actuator into the collar plate and install the actuator spring by squeezing the tips together and pressing it into the collar plate recess. 16 Wiper Seal Reassembly 17 Fit the wiper seal over the cable bolt tab on the actuator. 17 Seal Disk Reassembly 18 Replace the seal disk with the recessed side down.
technical service 19 Using a 2 mm hex wrench, install the seal disk bolt. Torque to 0.6 N·m (5.0 in-lb). 19 Cable Anchor Bolt Reassembly 20 Using a 4 mm hex wrench, install the cable anchor bolt and washer. Tighten to hand-tight. 20 Overdrive Pawls Reassembly 21 Apply a light coat of grease to pawl seats on the collar plate assembly. 21 22 Install the pawls in the collar plate assembly. Make sure the pawls are oriented correctly.
technical service 23 Carefully stretch the overdrive spring around into the grooves of the collar plate and each of the pawls. 23 Note: Be careful not to damage the spring upon removal by over stretching or kinking it. If the spring is damaged upon installation, replace it with a new one. Make sure that the spring is fully seated in the groove of the collar plate and the pawls. Collar Seal Reassembly 24 Pull the actuator arm so the pawls are retracted, and re-install the collar seal, lip side down.
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