jimmuller 

Looking for French HS info. When I built the Motobecane a few years ago I used a VO French HS. (I don't actually recall it being French but I'm pretty sure it is because of the "F" etched into the side and the metric tubing diameters.)

Problem is, it is indexing and the crown race shows considerable wear. I haven't had time to check the lower HT race yet. Anyway, I'm thinking about options. A perusal through Sutherlands shows French and ISO crown races to be the same. So in principle I should be able to use a VO crown race replacement, which they do offer, if the HT race is okay.

The VO French HS isn't very expensive so I could just replace the whole thing. But if the cause of premature wear is simply that it is made of soft material then it would be a temporary fix just like the current HS. Or I could find some other French HS with equivalent stack height, Gipiemme, Stronglight, whatever.

Of course it doesn't explain why it wore. Poorly aligned races?

Any advice? Thanks.

"Anyone who is crazy enough to ride a French bike ought to have his headset examined." - Paraphrased from Grouch Marx

qcpmsame 

Any pics Jim? Might help to see how the wear looks and just what's going on. One question about the VO headset, is the F after the threading numerals? I know that the Campagolo bottom brackets that are Italian threaded have 36X24F on them.

For some reason I keep recalling that even though the two standards are close, a problem can arise due to that slight difference in the thread's pitch. Maybe just a stray electron loose in the vast empty space of my cranium.

Bill

T-Mar

A quick fix for for 'indexing' headsets is to replace the caged ball bearings with loose ball bearings. Typically, the change in in ball to ball spacing prevents them from aligning with the pits in the races. However, that does not address the root cause. Conventional thinking in that the problem stems from a loose headset but Brandt contends it's lubrication failure.

Misaligned races are easy to identify from the wear pattern. The width of the wear track changes gradually from narrow on one side to wider on the other.

I don't know what VO's thread designation system was/is, but F can designate Italian threading, as F = fili, which means threads. It's best to check for an actual numerical designation.

SJX426 

Advice is based on your criteria. Mine is simple, I would start looking for a Stronglight competition after verifying that the treads on the steerer are still French.

jimmuller 

Okay, so I opened up the headset. It doesn't look nearly as bad as some I've seen, may be salvageable without major expense for now. None of the races look lopsided. Some slight indentationing (Is there such a word? If not, I just made one up.) is visible on the crown race but not on the HS races or top race. Definitely French dimensions and threads and the "F" is a single letter on one face of the top nut. (Not especially pertinent is that the ST is stamped Reynolds 531 Butted 16/13.) The caged bearings measure to be very close to 5/32". So I'm going take T-Mar's suggestion and install loose balls. Sutherlands says 22 top and bottom for most of the 5/23" races, particularly Campy. If this doesn't work or if it wears out quickly again I can try replacing just the crown race. At $3 it cheaper than a Stronglight Competition! If that still wears out I'll try SJX's solution, probably have to drop some coins on it though.

With a bit of luck I can have this done today.

Thanks for the input, guys.

qcpmsame 

Mine was just a random thought, it sounds like you have a grip on this now. Don't leave us hanging though, after you get finished, and probably ride a bit, let us know the outcome please.

jimmuller 

Well...I rode over to Belmont Wheelworks, took 5 minutes by bike to get there, 15 minutes waiting for someone to help me, another 5 minutes for him to figure out his billing mistake (long story nor worth repeating), then 5 minutes riding home. I came home with a tub of 75 Grade 25 5/'32" ball bearings. Time to open a beer.

I repacked the headset with 22 balls top and bottom and lots of Phil Wood grease (though lack of lubricant was not a problem). It's quite smooth now, not unexpected considering it went from 16 balls to 22 so they can't all drop into existing slots at the same time. No obvious indexing or free play. I'm going to ride it and see how it does. It doesn't exactly get daily usage so this may take a while. The crown race and lower HT race may wear away and I'll be able to tell by how it loosens up. In the meantime it seems just fine.

There is one interesting feature about the VO headset I hadn't notice before. With my Peugeot headset you assemble it by inverting the frame, packing the lower race with grease and bearings, insert the fork, turn the frame over holding the fork in the frame so the lower bearings don't fall out, then pack the upper race. The upper race on the VO headset is inverted, with the upper HT race facing outward and the threading portion being concave facing inward. That means you have to keep the frame inverted, pack the upper race, then thread it onto the steerer tub upward. It works just fine, just different from what I expected.

T-Mar

Let me clarify that, according to Brandt, the root cause is not "lack of lubricant" but "lubricant failure". When the bicycle is ridden in a straight line, the ball bearings experience microscopic vibrations called fretting, which results in dispersal of the lubrication film and metal to metal contact between the balls and race. The balls weld to the race and any subsequent rotation of the headset tears the softer material from the race and replenishes the lubrication film on the ball bearings.

jimmuller 

Got it, thanks. I did see some wear on the surfaces so I expect that sooner or later I'll have to replace the headset. It would be easier if I had the tool, alas.