Fork advice
 

On my '73 Raleigh RRA, I have always had a problem with the fork. On both it and my previous '73 International, I had noticed a fork blade misalignment looking down at the brake bridge/crown lug versus the dropout/hub position. I got Raleigh to replace both forks. When the replacements came, the crown race must have been set for JIS (27mm) instead of the 26.4 ISO dimensions I needed for the Campy NR headset (from the International). Since it was a relatively new LBS in Iowa, they didn't have a fork crown race cutting tool, so I wound up taking them to a machine shop (at different times).

The machine shop did the International fork perfectly (even though I didn't know anything about the proper dimensions at the time... no internet back then.) On the RRA fork, they messed up and cut the crown to ~25.96mm (what I measure now). I got some shim stock and have always shimmed it as tight as I could get it, and haven't noticed any real problems with it. However, I would now like to get it fixed.

Suggestions? Tom Kellogg from Spectrum Cycles told me via email that they could braze the crown up and re-machine it. It would damage the paint so repainting would be required, and he didn't know whether their standard white would match or not.

The shadetree mechanic solution would be to hit the crown race surface around the circumference with a punch, to slightly raise areas so the crown race fit tightly. Or JB Weld. Not sure its worth the brazing and machining and repainting, unless you demand perfection.

If it isn't broken, don't fix it.

Yeah, I had considered knurling or hitting it with a punch, but 0.4mm seemed like a bit of a gap. Still pissed at the machine shop :)

I was planning on doing Dairyland Dare this year, and speed of over 45mph might be anticipated, so wanted it good for that, though I have never had any problems with shimmy or anything over the years.

get a really fine point bunch and go at large spaced punches first. Test. If it still slips on easily do another round of punches in between those punches. 0.4mm isn't much and when you add up the cumulative effect of the punched on both sides you only need 0.2mm. I think you will find this will work. It has worked for me and many others many times.

Might be able to get a good machine shop to make you a "perfectly sized" permanent shim...............

Tried the center punch... it helped (with the shims), but nowhere near tight by itself. It was difficult to get both shims in however, so it is tighter than before. I may talk to a machine shop or two to see about the permanent shim. Or I may try JB Weld.

Has anyone on here done that before? I was curious as to what the right procedure would be on doing that.

Is there a smaller ID crown race (e.g. French?) that is otherwise compatible with the existing head set, that could be bored/honed out to match your oddball steer tube size?
I confess I don't have the problem fully visualized, I'm imagining that the steer tube OD is too small, but that makes me wonder about the integrity of the threads.:(

If you're going to depend on that fork so heavily, I'd suggest taking it off and shipping it with the desired crown race to someone like Tom Kellogg and have him build up the surface and then machine it to the correct dimension and the correct centered position. Then you can focus on training on the bike. These other techniques all run a risk of a misaligned fork. If I'm looking at descending the Alps at speed, I only want to do it on a well-aligned frame.

Or a professionally done knurling job.

That's a standard practice. I'm surprised that it took so long for someone to bring it up.

Thanks. I wasn't sure that knurling could make up ~0.2mm or not. I have the bike torn down to the bare frame right now for rebuild, so I'll look into machine shops in the area. The frame on this is full 531DB. The steerer is marked 531 as well.

GB, you had mentioned a Raleigh Pro fork you have in a thread recently. If this is something you want to get rid of, PM me.

Two options.

1). Beer can. Cut the aluminum into strips. Works.

2). (the proper way), get a Stein Knurling tool:

http://farm8.staticflickr.com/7181/6...ff172c97_z.jpg

You can drink alot of beer for the cost of the tool, but you won't be scoffed by the next person to remove your headset.

Heh! I'm the only one who ever takes it apart, so no worries over being scoffed at (other than scoffing at myself).

Stein tool seems a bit expensive for one use. I may check with the shop I had reface the BB and see if they might have one. Spectrum would do the rebraze fork crown for ~$80 + repaint, but Testors white is a near perfect match, so I might be able to just paint what was necessary myself.

I'm going to check around with some of the shops to see if they can do the knurling. I don't know any of the machine shops around here, but will call around as well.

If anyone here had a knurling tool such as balindamood posted above and would be willing to lend it out, I'd be interested in that as well.