INSTALL HAMMERSCHMIDT BOTTOM BRACKET
The HammerSchmidt bottom bracket needs to be installed in a specic order:
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).
B. Install the non-drive side bottom bracket assembly using the Truvativ GXP (or equivalent) bottom bracket installation
tool. The non-drive side assembly is right-hand threaded, so turn it clockwise to install and torque to
34-41 N·m (301-363 in-lb).
CHAINRING CHANGE UP - OPTIONAL
If you want to change your chainring size, now is a convenient time to do it. Locate the retaining ring on the
HammerSchmidt mechanism crank arm and use a athead screwdriver to gently pry the retaining ring off the ring guide.
Remove the ring guide and chainring. Install your other chainring. Re-install the ring guide and carefully press on the retain-
ing ring using the athead screwdriver. Make sure the retaining ring is fully seated in the groove of the ring guide by rotating
it a couple of revolutions.
INSTALL THE COLLAR ASSEMBLY - PART I
A. Get Your Disk on
Check that the seal disk for your frame’s ISCG standard (ISCG 03 or ISCG 05) is installed. If you need to change out
the seal disk, use a 4 mm hex to remove the cable anchor bolt and a 2 mm hex to remove the seal disk retaining bolt
then switch seal disks. Make sure the recess on the seal disk anchor bolt window faces down. Re-install the cable
anchor bolt until it is hand tight. Re-install the seal disk retaining bolt and torque to 0.5 N·m (4 in-lb).
B. To Space or Not to Space?
The collar assembly must sit ush 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.
If your frame’s ISCG tabs are ush with the bottom bracket shell face, you do not need to add any spacers. If your frame’s
ISCG tabs are offset inboard of the bottom bracket shell face, you will need to add the same amount of spacers you used
when facing the ISCG tabs in the Frame Preparation section in order to make the surface ush (you wrote this down
remember?). Locate the ISCG specic spacer(s) you need.
68 mm bottom bracket users! You must add an additional 2.5 mm of spacer thickness to the ISCG spacers you needed
above. This will complete the spacing requirements necessary for HammerSchmidt.