6400 West 105th Street / Bloomington, MN 55438 / www.problemsolversbike.com
499039 12/19 | 85-001053_INST_B
BUSHNELL
™
ECCENTRIC BOTTOM BRACKET INSTRUCTIONS
c. Reassemble. You’ll need to orient the main bottom bracket shell body to
match your bike setup. For tandem applications, the 4mm head of the
wedge bolt should face the drive-side of the frame, opposite the captain
chainring. For solo builds, the bolt head should face the non-drive side,
opposite the standard chainring(s).
When reassembled, the wedge nuts and wedge bolt should have a little
side-to-side play—not interfering with the wings (figs. 4, 5).
2. Install the EBB into the frame.
a. Insert the EBB into the frame’s bottom bracket shell and position it to be
centered from side to side.
b. Rotate to the EBB to position the wedge bolt at 3 o’clock when viewed
from the drive side, 9 o’clock from the non-drive side (fig. 6).
c. Use a 4mm hex wrench to cinch the EBB into place (fig. 7).
3. Install the bottom bracket and assemble the drivetrain.
a. Grease the EBB threads as well as the bottom bracket cups (fig. 8).
b. Install the bottom bracket cups, crankset, chain and rear cassette/cog
per the manufacturer(s) instructions (fig. 9).
4. Adjust chain tension.
a. Loosen the 4mm wedge bolt.
NOTE:
The bolt must be loosened until both wedges are free.
Otherwise the EBB will not rotate.
b. With the chain installed, rotate the EBB forward using a 6mm hex wrench
(fig. 10).
c. Position the EBB so that the chain is tight, then back it off just slightly.
d. Tighten the 4mm wedge bolt to 8.5–10Nm (fig. 11).
e. If your chain is too loose or too tight, adjust the EBB forward or aft as
necessary. For single speed drivetrains, ensure that the front chainring
and rear cog are aligned in the same plane.
NOTE:
Side-to-side adjustment of the EBB to optimize chainline
is permitted ONLY if the EBB does not extend outside the frame’s
bottom bracket shell.
WARNING:
A chain that is too tight will cause premature wear or chain
breakage, and a chain that is too loose may derail, causing a loss of control
and crash.
ONGOING MAINTENANCE
Check the EBB wedge bolt and chain tension before every ride. Adjust and
tighten as necessary. Periodically remove, clean, grease and reinstall EBB to
avoid corrosion and seizing.
WARNING:
Improper installation of bolts may lead to product failure, causing
serious injury. Do not exceed specified torque values. Periodically inspect bolts
and retighten if required.
WARRANTY PROCESS
If you and your shop think your Problem Solvers product is worthy of a warranty
inspection, please return the product to the original place of purchase,
accompanied by a sales receipt.
For complete warranty information, visit problemsolversbike.com/safety
Figure 9
Figure 10
Figure 11
Figure 6
Figure 5
Figure 7
Figure 8
Figure 4
