Replacement bearings for Stronglight JDX94 headset

[mzjo]

IProvoked by a couple of other topics here I have started thinking of and looking for replacement races and rollers for my old JDX 94 headset. I don't mind buying a complete headset but they (and the Miche Primato which is identical) don't seem to be very available (except perhaps on E-Bay which I don't use and which seems to deny me access to anything other than french Bay).

The question therefore is is there a 1" threadless headset which uses the same bearings as the vintage Stronglight and Miche headsets - and which I could cannibalise. I have an added interest because I am hoping (although I haven't yet tried) that the same races are used in the semi-integrated 1" threaded headset in the Vitus. Anything else out there? Or could the Stronglight cartridge bearings in the current deluxe A9 be made to fit (seems a bit unlikely to me)?

[Torslanda]

You'll need to sit down and measure the originals but you might find replacement rollers HERE .

Regards races, I might be being a touch thick but could you not simply reverse the positions of the races in situ? My recollection is they're the same size but haven't one to hand to check.

Your other suggestion of modifying to take a cartridge bearing depends on your machining skills...

[Brucey]

the races cannot be swapped about because the inner race is a smaller diameter than the outer race. Sourcing/making new rollers is not difficult (you can buy a pressed steel outer roller bearing for about three quid that contains rollers that you can trim to size) but the original acetal carriers will be worn and the rollers won't stay put during assembly unless the assy is well greased.

The seating angle for the races is not one that is shared with any modern cartridge bearing and the cups don't have a very great wall thickness, so there is limited scope for modification to accept a different bearing.

So I don't think that there is much scope for improvisation; you really need the correct bearings to make a repair.

Not being a lover of these headsets anyway ( I think they are perfectly horrid things that should have never seen the light of day in the first place) I have relatively little interest in refurbing one.

cheers

[Torslanda]

[Zhukov] Well! That's me told! [/Zhukov]

[Brucey]

I wondered about swapping the raceways over myself years ago, and then someone asked me to look at their bike which had 'steering that was not quite right' and they had inadvertently swapped the parts around, giving incredibly bad steering I think. You can see the size difference here



cheers

[Torslanda]

 

It's a sense of humour thing...

[mzjo]

I wondered about swapping the raceways over myself years ago, and then someone asked me to look at their bike which had 'steering that was not quite right' and they had inadvertently swapped the parts around, giving incredibly bad steering I think. You can see the size difference here



cheers

As I recall I swopped the entire assembly top for bottom (keeping the two races together with the bearing and in their original positions) which has worked but is obviously not a solution for eternity. The threaded headsets being unavailable, I was wondering whether the bearings from a Miche Primato 1" threadless headset were the same (so that I could buy a new one to raid the bearings from, if I could find one).

Alternatively does the JDX94 have the same stack height as the modern version of the A9 (allowing me to fit the ball-bearing version to please Brucey)? I still have the problem of the semi-integrated headset on the Vitus 992 to deal with but that way I might gain some spare bearings to provide a short-term solution (asking Look directly may be the only real solution of course).

thanks Jo

[Brucey]

I agree replacing the threaded 1" headset and keeping the spares for the semi-integrated one makes sense if (as I suspect) the latter isn't easy to replace.  ISTR the miche primate used the same bearings at one point, but I bet they later revised the headset and kept the same name or something....

cheers

[rogerzilla]

How much does it cost to have a headset changed these days?  The tools are about £90 all-in (I still find a hammer and punch works best on most crown races, although I do have the proper tool too) and can pay for themselves after not all that many headset jobs.  Forget reamers and facers, it's never economic to buy those unless you're running a shop (and they need regular sharpening).

[Jakob W]

At my LBS, about £10-15 (which seems cheap to me).

[Torslanda]

Labour varies quite a bit, new cartridge bearings in a semi or integrated headset is quite a quick job, removing and pressing new cups is a little more labour intensive. Steel external cups can be tapped in - especially in older frames - but alloy must be pressed and kept square to prevent distortion.

[mzjo]

How much does it cost to have a headset changed these days?  The tools are about £90 all-in (I still find a hammer and punch works best on most crown races, although I do have the proper tool too) and can pay for themselves after not all that many headset jobs.  Forget reamers and facers, it's never economic to buy those unless you're running a shop (and they need regular sharpening).

I must admit the idea of paying someone to do this had not occurred to me. I don't think my LBS would charge very much but I tend to use them for things I can't do (like retapping italian BB threads).