Stronglight P3 Headset question
 

I have this headset (I think a P3?) - it keeps coming a bit loose every couple of months, the shop I used to go to told me it was normal and I just had to get used to tightening it from time to time. Not super, unsafe loose, but enough you can feel "play" when you apply the front brake with any force...The shop guys told me I think that I could just tighten it using a spanner?
I see this old thread: https://www.bikeforums.net/bicycle-m...t-headset.html
but cannot find the diagram it seems to reference...What are the tools/steps I need to take to tighten this headset?

The shop I used to go to went out of business and the place who helps me now didn't seem to know how to adjust it. They are trying to convince me to get rid of it for a campagnolo nuevo record (which would match other stuff on my bike but I also have a stronglight crank that this goes nicely with) I think I also saw online stronglight made an updated lock ring that used flats for a wrench instead of those pinholes - should I get that? Would it help with not having to tighten it up so often?

https://cimg3.ibsrv.net/gimg/bikefor...3b667ea178.jpg
https://cimg6.ibsrv.net/gimg/bikefor...beb36ad572.jpg
https://cimg8.ibsrv.net/gimg/bikefor...049b256aeb.jpg

I will assume that the top nut has decent amount of thread engagement. If there is room, maybe ditch the thin washer to add 2 turns?

Agree with repechage, remove the washer/spacer for a better bite.

Before following advice of the shop, your steerer may well be too short for a Campy NR…check your stack height before purchasing a headset that may not work.

Is that a Bernard Carre-built frame?

Thanks – I will think about removing the thin washer, tho I have a vague memory that it may have been necessary for some reason...
- yes it's a carre frame you can see on some of my other posts...

https://cimg7.ibsrv.net/gimg/bikefor...3c3543726c.jpg

The tools needed are a pin spanner like the Park SPA-2 for the locknut:
https://www.parktool.com/assets/img/.../SPA-2_004.jpg
And the VAR-78 or a slip-jaw water pump pliers for the threaded race.
https://cimg4.ibsrv.net/gimg/bikefor...03d760dac3.jpg
https://cimg1.ibsrv.net/gimg/bikefor...e74f45e36f.png
It can be difficult to get the pin spanner to apply enough torque to the locknut to hold securely; maybe that's the problem you've had. You can replace the locknut with one from a different headset with the same thread spec so you can use a real wrench to torque it down securely. Or, just use the pliers on the locknut.

This is probably the missing diagram you reference. Note that later versions of the P3 headset used a more standard locknut with wrench flats:
https://cimg5.ibsrv.net/gimg/bikefor...e7782d5278.jpg

JohnDThompson Thank you! Yes - that is exactly the diagram I was trying to find

If I try to find one of those newer lock rings with the flats - do I have to make sure it's french thread? or is that a given that it would be

A headset shouldn't loosen so yes properly adjust it so that does not occur. The advice about checking for stack height is a good one. The campy if I remember has a pretty decent stack height and some of the french headsets do not.

The P3 has a pretty low stack height…about 33 mm. Campy has about 39…same for Stronglight V4 or A9 or Delta, just to name a few others that you might encounter with French threading. Generally, I feel good about a headset stack height if I have a minimum of three full threads of engagement for the locknut. If I am cutting the column, I will measure carefully enough to fill the locknut with as many threads of length as possible without bottoming out. It would be interesting to see how many threads are engaged on the headset in question, but it appears that with the extra washers installed, there *might* be enough fork column for a 39 mm sh headset. As suggested by others, If three threads are currently present, my first move would be to get a proper pin tool to tighten the locknut FIRMLY. Failing that, my second move would be to get a standard Stronglight hex locknut and tighten down. The P3 ( and V4) were good headsets in my opinion….

argh, I was going to suggest the pin tool Grand Bois made specifically for Stronglight headsets, cool tool but I see it's no longer listed on their website.

https://cimg7.ibsrv.net/gimg/bikefor...57eea967ff.jpg
https://cimg8.ibsrv.net/gimg/bikefor...cb4af30e3b.jpg

I don't think SL ever made a hex-head top nut, I think they were all octagons. Sorry to quibble...

It reminds me of when Tom Fogerty left Creedence Clearwater Revival and the band continued on as a three man quartet….

Yes, the thread has to match. Stronglight made the P3 in both metric and English thread. Metric thread may be more difficult to source in North America, alas, but it doesn't have to be a Stronglight piece; any 25 x 1mm headset locknut will suffice.

Thanks, good to know.
I just got the thing apart - and (doubtless I'm getting the terminology wrong here) but that slim washer is needed because the steering column is almost too long - I think the lock nut is almost at it's limit with available threads or is maybe already bottoming out. I remember now the guy at the shop said he could either cut the steerer shorter or add a washer.
maybe in addition to the french threaded locknut with flats I should look for another washer or a thicker one. Would that be something I could just get at a home depot type place? edit - now I realize it needs the flat part to match the steerer tube - so maybe not
I'm in germany it's called bauhaus here

If so that would explain the "loosening" of your headset - it's not locked in place by the presure of the top nut.
Headset shims are cheap, put one on and tighten like you mean it, then ride it a while to see if it's sorted.

Okay that makes sense - Thanks

I've got it all back together and tight (for now) and will look into getting a washer and possiblly a new lock nut.

Def cheaper than a campy record headset for 150 that the shop dude suggested. It would look nice with the other italian components though

I would avoid shortening the steer tube; that limits what headsets will be able to fit in the future. You can add as many washers as you need to make up for a too-long steer tube (they can be standard 1" ID washers available from any bike shop), but you can't lengthen a too-short steer tube if the headset you want to use is too tall.


You don't need a special washer, those made to fit a 1" headset will work fine. Nor does it need the flat spot; the toothed washer (part #104 in the diagram) has a flat spot, so you don't need any more. Standard threaded headset washers will have an anti-rotation key that you may need to file off. Spacers designed for 1" threadless headsets will also work, and they don't have the anti-rotation key.

This type of Var tool for various pin applications is stout enough to tighten the locknut pictured in the original post as well…
https://cimg4.ibsrv.net/gimg/bikefor...4c0f438f3.jpeg

My Carre, a work in progress, has steerer cut longer for use with Campy NR headset. I’d measure your stack height, as I recall 33mm for a Stronglight and 41 mm for a Campy…thus the steerer tube is cut around 10mm longer to accommodate a Campy NR headset…maybe your Carre was built for a Campy.
https://cimg3.ibsrv.net/gimg/bikefor...7ff65f7de.jpeg

150 euros for a Campy NR headset? You said you were in Germany, right? I'll bet you can find one for less than that but honestly the stronglight headsets are good quality.

Every French “Campagnolo” bike should have a few French parts supplied in lieu of Campagnolo. A Stronglight headset is a perfect place for one of the substitutions. I am a fan of the quality and durability of of most Campagnolo parts, but the ( Nuovo) Record headset is not one of their better efforts….precision machined, but not up to the rest of the gruppo in terms of durability and definitely not tolerant of even slight misadjustment. Stronglight headsets have always been excellent. One other item related to the OP’s P3 and the next model up V4 models…..The toothed washer makes the a bit fiddly to adjust…You have back off the locknut enough to lift that washer enough to free the adjustable cup for adjustment, tighten again, and then check for proper preload…and the repeat as necessary. There is normally a bit of play with the toothed washer against the flat of the steerer which sometimes makes things a bit tricky to hold the adjustment while tightening the locknut, but once tightened these are usually rock solid against loosening. One other word of caution should you decide to switch headsets….The existing P3 likely has a crown race diameter of 26.5 mmm or possibly 27.0….A Campagnolo will have a 26.4 mm crown race which will require machining with a proper cutter. (Stronglight V4 headset on a French “Campgnolo” bike, still perfectly smooth and in use since 1971….although you would never guess that it is mostly Campagnolo equipped as everything pictured is French…)
https://cimg3.ibsrv.net/gimg/bikefor...1670b12f9.jpeg

Very tricky holding the crown race in a lathe chuck, and probably better to grind it as it is chrome-plated.
Almost certainly better to re-do the fork seat.

Thank you everyone for all these comments and tips. My frame was likely built for campy, when I posted the pictures of the frame here, repachage pointed out that the dropouts certainly were. I have campagnolo hubs, brakes, derailleurs, shifters, and seat post, the cranks, headset, and bottom bracket are all stronglight.

It's a daily rider, gets locked up outside frequently in Berlin (never overnight) and there is lots of curb hopping, cobbles, and dirt/gravel paths I encounter. The shop I most recently used is all italian so of course they want to push campy stuff...Nice guys tho. it does look if I ever upgrade the P3 I would want a steel headset for durability, sacrificing a little weight.

Now at least I understand how the P3 works, and am comfortable loosening and tightening it. Along with a washer I may invest in a slightly larger pair of channel locks, or a mini plumbing style "monkey wrench" for loosening the bottom lock nut. I like the idea of not hacking off the steerer - keeping it original, even if as you can see I've already gone partial frankenstein with newer Japanese pedals, spanish handlebars, dia compe brake levers, and brooks seat.

I worded it poorly, but I agree that is what I meant to convey as well…