MRP S4 Installation Instructions

Step 7
Check the position of the top roller. Only when the bike is com-
pletely bottomed out should the chain be touching the groove in
the top roller. The top roller is designed to be a guide, not to
tension the chain at any point in the bike's travel. Improper top
roller position may result in broken or lost rollers, bent boo-
merangs and dropped chains. The best method for determining
the top roller position is to remove the spring or air pressure
from the rear shock and bottoming the bike out completely. Ro-
tate the boomerang so that the chain just touches the top roll-
er when the bike is completely bottomed out. Mark the position
of the boomerang. Please note that MRP chain retention devices
are designed to ISCG and ISCG-05 standards. Our experience is
that some frame manufacturers position the tabs not in accor-
dance to the standard. These frames may require modifications
or special installation instructions. If you find you do not have
enough adjustment, it may be due to the frame manufacturer not
following the standards. Please contact MRP for further in-
structions for fit.
Step 8
Remove the drive side crank arm. Make sure that the boomerang
is in the position that you determined correct in Step 7 and se-
cure it. If you have ISCG or ISCG-05, tighten the ISCG screws.
If you are using a bottom bracket mount boomerang, tighten the
bottom bracket cup to the manufacturer's specifications. The
boomerang may want to rotate as you tighten the cup, so double
check the position after everything is tight. Reinstall the com-
plete crankset and bottom bracket according to the manufactur-
er's instructions.
Step 9
Finishing Touches. Make sure that all bolts and screws are
tight. Saddle the bike and bounce around, check to make sure
there is no interference between the guide and the suspension
action or linkage on full-suspension bikes. Check your chain
length by shifting through all gears. It should be easy to shift
through all gears, but not have a lot of extra chain slack. Keep
in mind that most full suspension frames require additional
chain length to accommodate for rear travel. Check chain
length with the chain on the largest rear cog and bottoming out
the bike.
THE MRP DUAL ROLLER SYSTEM IS
PROTECTED BY U.S. PATENT 5725450
MRPBIKE.COM
970.241.3518
580 North Westgate Dr.
Grand Junction, CO 81505

INSTALLATION INSTRUCTIONS

Thank you for purchasing an MRP chain retention system.
MRP invented the bicycle chain retention system in the mid
90's and forever changed downhill and freeride mountain
biking. MRP's patented dual roller system found on the
S4 combines ultra-reliable performance, quiet operation,
and near universal frame compatibility. To ensure the
best out of your MRP chain retention system, we strongly
recommend that you have a trained service technician
at your local bike shop install your MRP. A properly
installed MRP will function flawlessly every time!
We've designed the S4 to be simple to install.
Before beginning your installation, you'll typically
need these tools:
4mm, 5mm, and 8mm Allen keys, an appropriate BB tool
(for BB mount applications) and a pedal wrench
The S4 is
available in
three different
mounts, make
sure that you
have the right
MRP kit for your
bike.