Breeze3at
Experienced Member
Polishing Fork Lowers (or any aluminum)
Note: This is not a quick project, and the results are directly proportionate to the care and effort taken in each step. One full day from start to finish is my estimate.
There is a protective coating on the aluminum. This coating cracks and lets air & moisture in, causing those ugly dark spots. I use paint stripper to remove it, but have also heard that oven cleaner and/or Acetone will take it off. Some say HD powder coats the aluminum, but I’ve never had any problem using basic caustics to remove the clear coat on any aluminum on my Harleys.
The easy way to tell if there is a coating over your aluminum is to rub a small area with any kind of wax or cleaner and a light colored rag. If the rag turns black right away, it’s not coated.
After the front wheel and fender is removed, tape over the cowbells, chrome or rubber slider covers to prevent scratching. Several layers of tape are best. Cover EVERYTHING except the lower tubes to prevent paint damage. Good idea to cover garage floor also.
Caution: Paint remover is VERY caustic, and burns skin on contact. Wear rubber gloves and eye protection or face shield. Oven cleaner isn’t too pleasant on skin either. Acetone removes all the oil from your skin quickly.
Put a bucket under fork tubes to catch drippings and carefully apply the paint remover. The coating will bubble immediately. Wait a few minutes, then rinse the dissolved mess off with water. I like to repeat this process. Don’t use water pressure, it will splatter the remover onto good paint – guaranteed.
Put another bucket under the fork tube and start wet sanding. I use a spray bottle, but dipping in the water works too if you change water between grits. The grits I use are 320, 400, 600, 800, 1000, 1200. You can go to 1500 or higher but it’s optional. I cut the sandpaper in strips, and sand in alternating diagonals like polishing the toe of a shoe. This helps to prevent flat spots in the tube (very noticeable when completed). Turn the forks occasionally, the backside will be visible from the other side of the bike as well. Use your finger and clothes pin sticks or popsicle sticks to get the small tight areas. The more patient you are with each grit, the better your results will be. Be careful of sanding down the fork drain screw heads if you have them. When you finally get to the 1000 grit, you will have smooth satin aluminum tubes. You can stop sanding here and start polishing, or continue to finer grits.
Now start with the aluminum polish. I like Mothers but White Diamond, Busch’s. Eagle 1 or Clear coat polishing compound works. I use strips of rags like I did with the sandpaper and go at it. Most alum. polish should be removed before it dries. Now you are starting to see the glow. A few more applications, and you should have a nice shine.
No matter how hard you try, it will not be the hard bright shine of chrome. It’s a softer warmer shine, but most people won’t see the difference. I like to finish with some carnauba wax to protect the surface. There is not a lot of care required. I give them a good polish once a year with the alum. polish.
Caution: Paint remover is VERY caustic, and burns skin on contact. Wear rubber gloves and eye protection or faceshield. Oven cleaner isn’t too pleasant on skin either.
This is a messy project.
Of course I dispose of my dissolved paint residue responsibly.
A palm or random orbital power sander can be used, but care must be used to not sand flat spots into the round tube.
A drill motor with a polishing pad works well with the polish step.
Forks are the only part I would do while still assembled on the bike. Other parts (Rocker box covers, or engine covers) are not as accessible. Paint remover makes a MESS when not contained.
Note: This is not a quick project, and the results are directly proportionate to the care and effort taken in each step. One full day from start to finish is my estimate.
There is a protective coating on the aluminum. This coating cracks and lets air & moisture in, causing those ugly dark spots. I use paint stripper to remove it, but have also heard that oven cleaner and/or Acetone will take it off. Some say HD powder coats the aluminum, but I’ve never had any problem using basic caustics to remove the clear coat on any aluminum on my Harleys.
The easy way to tell if there is a coating over your aluminum is to rub a small area with any kind of wax or cleaner and a light colored rag. If the rag turns black right away, it’s not coated.
After the front wheel and fender is removed, tape over the cowbells, chrome or rubber slider covers to prevent scratching. Several layers of tape are best. Cover EVERYTHING except the lower tubes to prevent paint damage. Good idea to cover garage floor also.
Caution: Paint remover is VERY caustic, and burns skin on contact. Wear rubber gloves and eye protection or face shield. Oven cleaner isn’t too pleasant on skin either. Acetone removes all the oil from your skin quickly.
Put a bucket under fork tubes to catch drippings and carefully apply the paint remover. The coating will bubble immediately. Wait a few minutes, then rinse the dissolved mess off with water. I like to repeat this process. Don’t use water pressure, it will splatter the remover onto good paint – guaranteed.
Put another bucket under the fork tube and start wet sanding. I use a spray bottle, but dipping in the water works too if you change water between grits. The grits I use are 320, 400, 600, 800, 1000, 1200. You can go to 1500 or higher but it’s optional. I cut the sandpaper in strips, and sand in alternating diagonals like polishing the toe of a shoe. This helps to prevent flat spots in the tube (very noticeable when completed). Turn the forks occasionally, the backside will be visible from the other side of the bike as well. Use your finger and clothes pin sticks or popsicle sticks to get the small tight areas. The more patient you are with each grit, the better your results will be. Be careful of sanding down the fork drain screw heads if you have them. When you finally get to the 1000 grit, you will have smooth satin aluminum tubes. You can stop sanding here and start polishing, or continue to finer grits.
Now start with the aluminum polish. I like Mothers but White Diamond, Busch’s. Eagle 1 or Clear coat polishing compound works. I use strips of rags like I did with the sandpaper and go at it. Most alum. polish should be removed before it dries. Now you are starting to see the glow. A few more applications, and you should have a nice shine.
No matter how hard you try, it will not be the hard bright shine of chrome. It’s a softer warmer shine, but most people won’t see the difference. I like to finish with some carnauba wax to protect the surface. There is not a lot of care required. I give them a good polish once a year with the alum. polish.
Caution: Paint remover is VERY caustic, and burns skin on contact. Wear rubber gloves and eye protection or faceshield. Oven cleaner isn’t too pleasant on skin either.
This is a messy project.
Of course I dispose of my dissolved paint residue responsibly.
A palm or random orbital power sander can be used, but care must be used to not sand flat spots into the round tube.
A drill motor with a polishing pad works well with the polish step.
Forks are the only part I would do while still assembled on the bike. Other parts (Rocker box covers, or engine covers) are not as accessible. Paint remover makes a MESS when not contained.
