At this stage in the project, the bike is apart. I took the frame, sub-frame, center stand, battery box halves, headlight ears, license plate bracket and thFe handlebar controls to Brad at BFN Industries, a local company near me in Arvada, CO.
A week later, I picked up the parts from Brad at BFN Industries. The total price was $190 and change for bead blasting and powder coating. I think the price was very reasonable as I got quotes of close to twice the much from some other power coating companies in the Denver area and I’ve gotten notes that others have paid $500-600 for powder coating this many parts in other areas of the country.
When I closely inspected the right side handlebar control, there was a problem with the coating. It was uneven and lumpy. I took it back to Brad and he said it looked as if some oil or other surface contaminant was on the part even thought the sand blast and clean before coating. “It’s not right. We’ll take care that.” I appreciate that level of customer service.
The battery box brackets were rough when I took them in and they show that after being coated, but that’s part of the story for a 40-year-old machine, isn’t it? 🙂
Here’s are some before pictures of the parts.
I wanted to powder coat the swing arm, but not remove the drive shaft. So I came up with a “soup can sock” to prevent beads from striking the joint and the bearings.
Although I got away with my “soup can” method to avoid removing the drive shaft from the swing arm, it’s a bit risky and relies on the powder coat company to be careful when they blast the swing arm. Also, the temperature used to melt the powder coat is around 400-425 F. The swing arm bearings are sealed and the drip point of the grease used is likely closer to 500 F, but the heat may cause the grease to leak out of the drive shaft bearings. So far I have had no problems. That said, the safest approach is to remove the drive shaft coupling so you can remove the drive shaft from the swing arm. I purchased the tool from Cycle Works to remove the drive shaft coupling: you can read about how I did it here:
An alternative it to take the swing arm to your BMW dealer and have them remove the coupling which is about a 20 minute procedure. They can reassemble it for you as well.
And here are some after pictures starting with the unwrapping.
All the threaded holes look clear of coating but several need some cleanup at the beginning of the threads due to minor intrusion of the powder coat.
One area I need to clean up is a bit of over spray at the edges of the frame identification plate on the front of the steering head.
I got a note after my initial post that mentioned some over spray to clean up and heard about using Permatex Gasket Remover to soften and lift powder coat over spray. Here’s the stuff.
It is pressurized and comes out very quickly when you push the button. I found it best to hold it upright with the brush at the top and press gently until the white liquid remover is visible on the brush. Then apply it where you need to remove powder coat. I cleaned up the badge on the steering head and then moved on to the frame, sub-frame and controls as a small amount of powder coat at the top or bottom thread was evident. When I only needed a small dab, I used a q-tip to apply the liquid remover just where I wanted it.
I put a little of the gasket remover on the bolt threads and then starting it in the hole. The gasket remover softened the powder coat in less than a minute and by working the bolt in and out of the thread, it cleared the powder coat very quickly.
This worked well for all the threaded holes. About 50% of them needed to be cleared at the start of the thread.
The rear brake bushing is a close fit to the brake pin since it holds grease. In this case, I used my Dremel tool with drum sander to clear out the powder coat. I forgot to indicate this hole should be blocked when I dropped the parts off.
It took me about 2 hours to go over all the holes being sure bushings, bolts and such smoothly fit the threads.
Be careful using the gasket remover so you put it where you want it and it doesn’t inadvertently get onto the frame. Keep water and a sponge handy to wipe it off immediately if you get a dab in the wrong place.
I like the look of the powder coat, and clean up wasn’t a PITA. Based on the price and finish, I think powder coating is a viable option for painting tubes and small parts. I’ll have to see how well it wears over time.
I also took a couple pictures of the “in Boxes” parts pile with restored/refinished parts. This is what I start from when I begin to reassemble the bike.
There is work to be done on the engine, transmission and clutch and more cleaning and polishing of a few items such as the steering damper knob below. But, I’m getting pretty close to that point we all read in a Haynes or Clymer manual, “Reassembly is the reverse of disassembly.” 🙂