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Well, they arrived with the freewheel still on, which was a bonus for me, but it turns out the freewheel was never removed for the sandblasting, so it had lots of grit inside making a crunchy sound when it turns.
Given the rarity of these freewheels (I haven't been able to find one like it anywhere) I decided to take it apart and clean it up. It seems that very few people do this, and not much info was available that I could find on how to do it, so I did it anyway.
It turns out the hardest part of the whole project was getting the sucker off the rim. To do this I modified a Park FR-6 freewheel removal tool.
This part has been done by lots of people, and the tool and modification info is pretty easy to find. I removed two teeth, and narrowed the other two from 8mm to 6mm.
I also shortened the teeth a little so the tool would sit flush on the freewheel.
The modified tool had a couple problems: It slides back and forth on the freewheel, and it likes to pop off when I try to torque it. Fortunately, I was able to solve both issues with a lag bold I found amongst the strange things laying around in my basement.
It fit over the tool, and through the axle hole and the washer and nut went on just perfect on the other end. And for a few minutes, I even had a novel way to carry it around.
It took a while to figure out how to get the rim to hold still so I could wrench that freewheel off. I thought of all sorts of things, but kept finding a lack of parts or tools to make it happen. I finally ended up sticking a 2x4 through the spokes to stand on, and butted one side up to an unfinished cabinet. That held it still enough to put some real torque on it without it moving much.
A bit of extra leverage also helped:
It finally broke lose, and was then easy to turn.
Just for reference, what I have is a 23-tooth, single speed, freewheel, made in France by a company called Atom. Or maybe that's just the name of the freewheel. Well, like I said, I haven't found anything like it on the internet.
It seems most freewheel bearing covers have left-handed threads. Although, a few have standard threads. I started out assuming it was a lefty, and I got lucky. Of course, to keep everything from moving around, I had to put the freewheel back on the rim. A little tapping with a punch and hammer got it loose pretty easy.
There is a pin-spanner tool available by Park to get these things open also; an SPA-2. But I don't have one, and the punch and hammer trick worked well just by light tapping, so its all good. Here is the freewheel with the cover removed:
I had expected ball bearings to fly everywhere, so I put the freewheel in a bowl first. Well, they didn't fly; just sort of sat there. But there were 50 of them, and there small! So why take chances?
With the bearings out, and also a washer, (Or is it a spacer?) the spring and lever mechanism is exposed. This is really neat! I've never known before how these things work just by making some clicking sound.
Lifting the sprocket off the center assembly, I discovered another set of 50 ball bearings underneath! Fortunately, these didn't move around much either, since I didn't have it in the bowl at this point.
With all the ball bearings and the sprocket out of the way, that just leaves the center assembly. Which is obviously still full of sand and grit.
The levers and springs were easy enough to remove. Although, as I'm now writing this up, I realize I've put the springs back in upside-down!
The freewheel is now completely disassembled and ready for cleaning. The good news is that because the freewheel hasn't been used since the sandblasting, the grit inside hasn't caused excessive wear yet. And since I'm cleaning it all out, it won't in the future either.
I used carburetor cleaner to get the grit and grease off. Then I used Krud Kutter to get the carb cleaner off. Water got the Krud Kutter off. My hands were filthy of course, so no pictures.
With all the parts clean and dry, I started by putting the springs back on the center assembly. Now you can see pretty clearly the springs installed upside-down. The shorter "arms" should be toward the inside, and the longer "arms" should be facing outside. After this writeup I'll have to go back and fix that...
With that done, I put some grease on both ball bearing tracks on the sprocket to help the bearings stick in place.
The 50 ball bearings are now in place. This part is a bit tedious, but tweezers help.
With the bearings in place on the back of the sprocket, I put the center assembly down onto the sprocket, and it now holds the ball bearings in place. The whole thing can now be flipped over. I haven't installed the levers yet. They would stick out and make it harder to get the center part over the sprocket and bearings.
Ok, now the levers are back in place. (At this point, I still didn't know the springs were upside-down.)
Bearings and the washer/spacer thing back in place. I managed not to loose a single ball bearing!
And then the cover goes back on. Early on, I noticed a "P" mark on the front of the sprocket, and no markings at all on the back. I used that to make sure I got it back together the right way.
The freewheel now turns easy, has a nice sounding click to it. No more crunchy! I'll have to open it back up later and put the springs in right, but it seems to work fine the way it is. And maybe I'll add some grease to the spring and lever parts too while I've got it open. Maybe it won't need it. A lot of excess grease came out the seams during the first few turns. Perhaps its distributed itself well enough already. For now, I'm jazzed I don't have to try to replace this thing. Although if I had the part available, I would have replaced the washer/spacer thing. Its only as thick as a couple sheets of aluminum foil. And it was the only part that looked like it had any wear at all.
