How to Adjust Push Rods for a Harleyby Kyle McBride
Harley-Davidson adjustable push rods allow for the use of non-stock or performance cams. These types of cams will have different profiles than the stock cams with variations in lift and base circle diameter. Stock, non-adjustable push rods will likely not be the right length for use with the new cams. Adjustable push rods are set to the proper length with a few basic tools.
Raise the bike with the bike lift. Place the bike lift close to the rear of the frame so that the bike is supported with the rear wheel off the ground. Put the transmission in first gear.
Remove all four push rod cover clips by hand or with pliers if they are stubborn. Use caution and do not bend or ruin the finish on the clips. Pull the upper and lower push rod covers from their recesses in the head and block, respectively. Inspect the push rod tube O-rings for damage and deformities.
Hold the covers up to expose the adjusters. Push the covers up and clip a clothespin to the push rods to hold the covers in place.
Roll the rear wheel until the rear exhaust valve cam is in the Open position or when the maximum lift on the rod is detected. Now you can adjust the front exhaust push rod.
Extend the adjuster on the front exhaust push rod until the rod can spin freely but has no up-and-down slack. Tighten down the lock nut with wrenches (most likely 5/16 and 3/8 inch, but this may vary by push rod manufacturer). Recheck the adjustment once the lock nut is tight.
Roll the rear wheel until the rear intake cam is at maximum lift. Adjust the front intake push rod at this time. Repeat this process until all four valves are adjusted.
Put the O-rings back into their recesses. Carefully extend the upper and lower push rod cover tubes back into their recesses. Reinstall the push rod cover clips by hand.
- close Always roll the rear wheel as it would roll if you were moving forward. Never rotate the engine backwards. The geometry of the internal parts is not designed to allow for reverse rotation, and serious damage may occur.
Items you will need
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