La Brea Bike

This is new one for me. Any help on where this is located in the headset? Unfortunately I can't find any exploded views of this set up. Oh, and there is a non-broken one in the kit Thanks!!!

oneclick 

That's a special washer that goes between the top cone and the locknut; the cone should have a pin that fits in one of the holes. You adjust the cone, and then drop the above washer on top of the cone so the hole matches the pin and the tongue matches the slot in the fork. Then you tighten the locknut down.

juvela

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photo is of lockwasher

the adjustable race has an upward facing pin which is designed to fit into one of these holes

the pin is often knocked off by heavy handed mechanics

if yours is gone you should be able to see where it erstwhile was in residence

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La Brea Bike

Got it! Thank You!!!

juvela

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btw -

we failed to note that if locator pin hath gone walkabout headset is yet perfectly usable


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oneclick 

And I should have added, that after you adjust the cone and drop the washer on the pin and tighten the locknut, you get to take it all apart and do it again because the tightening changed the adjustment.

verktyg 

May I add that most of the headsets on entry level and lower priced European bikes from the 70's were pretty poor quality. Most were made of chrome plated case hardened steel. The chrome in the bearing race areas quickly flaked off and damaged the thin case hardened bearing races. That was one of the causes of "indentations"!

Cheap case hardened headset with unground races.



I use the term indentations because the actual cause of headset bearing race failure is difficult to determine without being tested by a metallurgical lab. Everything else is GUESSING!



Getting back on topic, going all the way back to the early 70's I don't recall ever seeing one of those Peugeot headsets used on U-08 and PR-10 bikes fail from normal use. They were easier to adjust and stayed adjusted.

The pin in the adjustable top cup fit into the close together holes in the keyed lock ring pictured above which allowed for much more accurate headset bearing adjustment than the toothed lock washers on bikes like Gitane, also Lightrace and Stronglight P3 and V4 headsets.

Gitane headset.




Stronglight P3 & V4 headsets with toothed lock washers.


verktyg

oneclick 

I don't think you are correct.

There are 26 holes in the ring and 40 teeth on the washer, so to a first approximation the toothed washer arrangement has greater precision.

And because the pin must be smaller than the hole there will always be clearance, even in the case where it doesn't matter because the locknut is tight enough to prevent movement (as it should be); whereas with the triangular shaped teeth they will when tightened take a relative position where there IS metal-to-metal contact, i.e. zero clearance, so that is a source of error removed.

However, accuracy requires that the adjustment be *correct*; and a plain pair of locknuts can be set at finer divisions than either of the above, probably by an order of magnitude. I suspect the pin/toothed washer arrangement came about as a result of the fancier-looking headsets having less purchase for the tool (or a special tool being required) and so many of them were not sufficiently tightened, becoming loose, and gathering complaints.