How do I Install Mid-Frame Air Deflectors for a Harley Davidson?

by Alexis Rohlin

Mid-frame air deflectors attach onto a motorcycle frame just below the seat. Mid-frame deflectors are a type of thermal deflectors.They are used to direct heat away from the rider's legs. Harley Davidson motorcycle passengers often suffer burns from coming into contact with the engine's heat on their right ankle and inner leg area. Some deflectors are designed to both move away engine heat and send on-coming air towards the rider during driving. You can buy and install a separate injection-molded trim with chrome accents as well.

Step 1

Remove the bolts from underneath the motorcycle seat with a socket wrench and remove the seat to reveal a square opening in the frame. Or, if you have a seat that can pivot, just flip it up to reveal the square opening. Remove the stock plastic cruise-control cable clip (if applicable) on the frame located near the end of the fuel tank and set it aside in a safe place.

Step 2

Insert the speed nuts onto the slots located on both ends of the mounting strap. Align the edges of the speed nuts to the angled ends of the mounting strap.

Step 3

Insert the mounting strap through the square opening of the frame, onto the downward slanting metal panel which is underneath where the seat goes on the motorcycle. Place the strap so that the speed nuts align over the 1/4-inch holes in the metal panel of the frame.

Step 4

Stand behind the motorcycle in a position that allows you to look up at the underside of the metal panel, which is beneath where the mounting strap was placed. Insert into the top hole of the panel's left hand side a 3/4-inch button head screw. Push it in and hand tighten it all the way until its head sits against the underside of the panel. Insert into the panel's right hand side top hole a 7/8-inch button head screw. Push it in and hand tighten it all the way so that its head sits against the panel's underside. Do not use a screwdriver, only hand-tighten the screws to keep the strap from moving and shifting out of position.

Step 5

Apply liquid dish soap onto the exterior of the well nut. While looking up at the underside of the panel, insert the well nut into the lower hole of the panel's lefthand side.

Step 6

While still looking up at the underside of the panel, remove the panel's top left hand side 3/4-inch button head screw. Position the top screw hole of the left hand side deflector over the panel's top left hand side screw hole. Place a 3/4-inch washer onto the 3/4-inch button head screw and slide it down so that it rests against the screw head. Re-insert the button head screw with washer assembly into the panel's top left hand screw hole. Do not tighten it yet. Insert the small screw with washer that came with the kit into the panel's top right hand screw hole. Leave the screw loose. Push the deflector against the exterior of the frame and tighten the screw to a torque of 25-35 pounds per inch with the torque wrench.

Step 7

Remove the panel's left hand side lower screw. Slip a washer over the left hand screw you removed, sliding it all the way down until it rests against the screw head. If you have a cruise control cable, slip the cable clamp over the cruise control cable. Insert the panel's lefthand side lower screw through the cable clamp on the cruise control cable, up through the left side deflector's screw hole, and into the mounting strap speed nut. Push the deflector against the outside of the frame rail and tighten the screw with a torque wrench to a torque of 25 to 35 pounds per inch.

Step 8

Insert the U-clip onto the top part of the large hole near the deflector and metal plate on the right hand side opposite of the deflector. Position it so that the U-clip's barbs are resting against the plate. Move the cruise control cable, if you have one, so that it is sitting above the rounded area of the U-clip.

Re-install the seat and secure it into place with bolts or tilt the seat back down into position.

Items you will need

  • Socket wrench set
  • Mid-frame air deflector kit
  • 3/4-inch button head screw
  • Screwdriver
  • 7/8-inch button head screw
  • Liquid dish soap
  • Well nut
  • Small screw with washer (kit provided)
  • Torque wrench
  • Cable clamp
  • U-clip

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