SF-B1877 Bearing and Middle Axle Replacement

How to replace the bearings, middle axle, and hardware on the unit. Tools required for this task are a socket wrench, crank puller tool, snap ring pliers, mallet, and screwdriver.

Here is a quick guide that will assist you with the proper procedure to successfully replace the bearings and middle axle on your unit. 

STEP 1: Remove the flange nut that secures the left crank arm to the middle axle using a 14mm socket wrench. 

STEP 2: Thread the Excrator Tip/Head of the crank puller tool into the crank arm by hand until it stops. Then thread the rod into the crank arm to push the crank off the middle axle. 

STEP 3: Remove the middle axle plastic cover, exposing the axle and C-Clip. Using Snap Ring Pliers, remove the C-Clip.

STEP 4: Switching over to the right side of the unit, repeat the same steps to remove the crank. 

STEP 5: Using a crosshead screwdriver, remove the screws holding the belt cover and expose the drive belt within.

STEP 6: With the drive belt exposed, proceed to remove the belt. Grab the belt with your fingers and pull it towards you sliding it off the belt wheel. Be cautious that you do not pinch your fingers.

STEP 7: Using a rubber mallet, tap the middle axle from the left side toward the right side to slide it out of the frame.

STEP 8: Insert a narrow piece of pipe or tube that you can strike with the mallet to push the bearings out of the frame. Repeat the process for both sides.

STEP 9: Insert the new bearings by hand, making sure they are flush with the frame, and finish off by tapping the bearing with the mallet to fully insert it into the frame. Repeat the process on the left side.

STEP 10: When reinstalling the middle axle, make sure that the hardware is installed in the correct order. Insert the wave washer and spacer before inserting the axle through the right side. 

STEP 11: Insert the middle axle into the frame.

STEP 12: With the axle installed make sure that you push the belt wheel far enough that you can find the groove for the C-Clip.

STEP 13: Using the C-Clip/Snap Ring Pliers insert the clip onto the axle and make sure it lands in the groove. You should hear a "click" as it snaps in the groove.

STEP 14: Reinstall the plastic cap and crank. Secure the crank by tightening the flange nut.

STEP 15: Center the belt on the tensioner pulley and loop it over the belt wheel making sure it sits correctly.

STEP 16: Using your left thumb as support, rotate the flywheel with your right hand to guide the belt around the belt wheel until it snaps in place. 

STEP 17: Reinstall the belt cover and secure it with the previously removed screws.

STEP 18: Finish up by installing the right crank and securing by tightening the flange nut. 

(NOTE: Pay attention to the position of the left crank arm. If the crank is pointing down then make sure the right crank arm is pointing up so that the cranks rotate correctly.) 

For more information, please see the video below:

Additional video support: (how to remove the middle axle 04:02)