ISG type guide bar installation
This season you have decided to unleash the horses and go big ? Installing a chain guide is a must! There are different systems and different mounting standards, but installing them is a fairly simple operation. Here is how to install an ISG type guide bar.
Tools : 1 Crank clamp / 1 5" BTR spanner / 1 4" BTR spanner / 1 Mallet / 1 workstand
Step 1
If your rear derailleur is equipped with a chain tensioning system (Shimano shadow), consider disengaging it to work more comfortably. If your rear derailleur is equipped with a chain lock (Sram cage lock) you can also use it.
Step 2
Loosen the BTR screws on the left hand crank.
Step 3
Loosen the bottom bracket clamping screw using the specific tool (in principle, this should be done by hand as the tightening torque is very low, but the tool has an indentation that allows you to use a spanner)
Step 4
Disengage the polarizer with a flat screwdriver.
Step 5
Remove the left hand crank.
Step 6
After disengaging the chain from the crankset, remove the right-hand crank (it may be necessary to tap the left-hand side slightly with a mallet to get the crankset out).
Step 7
Using a caliper, measure the distance between the ISCG legs. If the distance between two screws is 47.88 mm, the frame is ISCG03 standard (also called OLD). If the distance is 55.92 mm, the enclosure is ISG05 standard.
There are also BB standard chain guides on the market, which simply consist of a ring that is clamped between the frame and the bottom bracket shell. This allows frames with screw-on bottom brackets and without ISCG dropouts to be fitted.
Step 8
Install the guide bar by slightly tightening one of the 3 screws to hold it in place.
Refit the right-hand crank only. Test the transmission for proper operation, all gears should shift correctly. If this is not the case, remove the right-hand crank again, adjust the position of the chain guide and repeat the operation.
Step 9
Once the adjustment is satisfactory, remove the right-hand crank one last time, tighten the 3 screws of the chain guide and then reassemble the crankset according to the following steps:
• Lubrication and assembly of the cranks.
• Mounting and tightening the bottom bracket clamping bolt with the special tool (note that the clamping is done by hand, it is simply a matter of removing the play from the bottom bracket).
• Reposition the left crank pin. If it does not, the crankset is not tight enough.
• Tighten the BTR screws of the left hand crank gradually (alternating 1/4 turn on each screw) to the recommended torque using a torque wrench.
