Problem with forks

[chaterlea25]

Hi Richard,
Another idea came to me 
A brake cylinder hone would remove scores std but follow any locality
With an extended drive it would also go further down the slider????

John

[RichardL]

Gents,

Again, I've been slow to reply, so slow, I had to go back and re-read all or my posts and yours to remember what's been said.

Recapping: My stanchions with new bushings wouldn't push into what appeared to be smooth bores in the fork legs. Before trying any remedy, these new bushes came out with a lot of scratches. The legs do have some ovality, though I am unable to determine how much ovality through the length of the leg. No visibly obvious distortion on the exterior or interior.

I decided that honing inside the legs was the most readily available possible solution at my disposal. I bought a brake cylinder hone (pictured) that I thought would work for the job. The 2"-long stones avoid the bottom peg and allow me to get within about 3/4" bottom without an extension.

As Chaterlea John has noted, the hone may just be riding on the ovality. OK, fine, but I have to get the stanchions in the legs some how. I have gone through several cycles of honing the leg (I'm just working on one, for now) and cleaning up the scratches on the bottom bushing. Each time, the bushing comes back with new scratches and passes them (very lightly) on to the bore. I'm pretty sure the bushing is much softer than the leg, so don't know why it would scratch the leg. I will say, things have gotten looser and I can get the stanchion to the bottom of the leg, but the scratches keep coming. I considered the possibility of problems at the very bottom where I haven't honed, but that wouldn't explain why I was getting bushing scratches when I could only get the bushing three or four inches in.

You can see the bushing scratches and interior of the leg (and the hone) in the attached photos. (I was surprised I was able to get a respectable photo of the leg bore.)

As always, a sponge for your advice and thoughts.

Richard L.

[morris]

My twopence worth of thought Richard, but the thing is that the tolerances between bushes and sliders are very small. The smallest spec of dirt will pull a scratch already.
When I redid the forks I was pretty sure that the sliders where as clean as a wisthle but when I dismantled them after a couple of hundred miles the bushes showed plenty scratches all around.
Just get them to go up and down all the way without any rough spots.

[RichardL]

Wow. I hope all of this is not due to bad hygiene. I was stuffing in cotton rags and swirling them out, then followed those with microfiber. Nevertheless, thanks for the good advice. I will go for an even more aggressive clean. Suffice to say, the bushing-to-leg clearance won't be as small as it once was.

When I put the A10 forks together about 14 years ago there was none of this trouble.

Richard L.

[Jules]

Hi Richard, just looking at your slider bore photo, it does look like you have vertical scratches in the bore (not surprising) and I must say that I'm surprised (for a barn find) that there doesn't seem to be any obvious corrosion down there, although hard to see really. When you look at your bearing photos magnified up, it does look like something is "wiping" the bearing (look at the end of the bearing in places you cant see the edge any more) and I thought that corrosion/pitting would create something like that, particularly if the pitting has retained some of the honing material...….Maybe a more robust scrubbing with a brush and wash, rather than just wiping out with rags???