Loose crown race

Mike Muz · Jan 11, 2015

Happy Sunday evening, retrofolk

I have a small problem with a project I'm just starting. I have taken the 1" STX headset with cartridge bearings off, to be replaced with a DX one with proper balls :shock: in a race.
The only problem is, the part that fits on the forks is loose. :roll: By maybe 1mm :shock:
I think I have seen this problem mentioned here before, but can't find it.
Can anyone out there help? Is it a matter of getting the local frame builder to add some braze to the fork ?

Thanks in advance for your help

Mike

troje · Jan 11, 2015

Check if your DX headset is a JIS standard. It looks like your fork (and frame) is ISO standard, that requires a 26.4mm ID crown race. JIS is 27.0mm.

Sheldon Brown should clarify further if needed.

troje · Jan 11, 2015

Another giveaway is that the headset cups are pressed in the frame with too much ease, as JIS ID is 30mm vs. ISO 30.2mm.

Mike Muz · Jan 11, 2015

Re:

Hi Troje,

Thanks for your help

I measured the crown race at 27mm, and the cups that go in the frame at 30mm. Offered them up to the frame and didn't go straight in, so it will be ok I think if I get some braze put around the fork crown. It seems to be the right crown race for the headset.

Mike

Midlife · Jan 11, 2015

Way back when we used a centre punch to raise mounds of material round the seating area of the race on the top of the crown. If that makes sense....

Shaun

Mike Muz · Jan 11, 2015

Midlife":2h8diwnu said:
Way back when we used a centre punch to raise mounds of material round the seating area of the race on the top of the crown. If that makes sense....

Shaun

Hi Shaun,

Yes I know what you mean, but there is quite a gap on these forks I think.

Actually, I just went to the loft to measure with MR V Calipers. Roughly between 28.6 and 28.8mm

Mike

Midlife · Jan 11, 2015

That is quite a bit bigger ! I assume that its a threaded steerer?

Shaun

Mike Muz · Jan 11, 2015

Re:

Yes it is mate.

I have a few 1" Ultegra headsets that I could use if they fit better, but I want to keep as much DX on the bike as I can really

Mike

dyna-ti · Jan 12, 2015

When you say 'proper balls in a race' do you mean the thin metal carrier :?

Mike Muz · Jan 13, 2015

Re:

Yes that's the one fella

Left the forks at the local frame builders now.
Mike

Loose crown race

Mike Muz

troje

troje

Mike Muz

Midlife

Retro Wizard

Mike Muz

Midlife

Retro Wizard

Mike Muz

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Mike Muz

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