Threaded Headset / Problems with 1" Headsets

Hi - old thread resurrection, following on from the question above about any 1 inch headset fitting any 1inch fork with the proviso that it's the correct size steerer - can anyone recommend a 1" threaded headset for a late 90s Giant TCR? I've chekced the webz and I'm sure these frames were originally kitted out with 105 or Ultegra - and I have a Shimano 105 but it appears the crown race is loose. Could that be due it being secondhand/ old/ removed too much - or is it the wrong size. Can I just get a new crown race, glue it in place or is or is it just best to get another headset. Any advice welcome, and yes it's definitley a a one inch threaded Giant carbon composite fork

Follow the link in post #004 above and scroll down to the headset table.

The most likely explanation is that you have a JIS headset (27.0mm crown race) and ISO forks (26.4mm crown).

Get some digital Vernier calipers (about a fiver off Ebay) and check.

You shouldn't glue anything in place, the crown race should be an interference fit: if it's loose, it's wrong.

In theory you could get a crown race separately, but in practice a new headset will be easier to find.

The Stronglight A9 is not only a suitable headset for a Nineties build, but it's also a great headset.

Thanks SS - that confirms my suspicions and Bikepedia confirmed that the HP 1055 came in JIS and ISO sizes - cheers

A strip cut out of a coke can makes an excellent spacer if your crown race is a bit loose.

Greetings, got a bit of a issue with trying to fit this headset. Measured my fork steerer and headtube (158mm/188mm) which left 30mm. Assumed that a headset with around 30mm stack height would be fine. Bought a Dia-Compe Gran Compe SE Threaded Headset which had been told was 34mm stack. It would be all good however there is only a short ammount of thread ontop of the fork steerer (14mm) and therefore doesnt all clamp down as normal but leaves a space of around 10mm. I cannot add any spacers as the top cup is threaded and reached the end of the thread. I assume im going to have to find a headset with a larger bottom cup? Any advice would be appreciated and sorry if this is a bit of a dim question. Thanks

If I've understood you correctly, you have a choice:

• a new headset with a greater stack height;
  
• get your LBS to cut the thread further down the steerer.
  
  

Of the two, the second would be my choice. Finding another HS with just the right dimensions to fit within such a narrow margin will be a PITA and end up costing you two HS; getting the thread cut will be cheaper than a new HS and give you more leeway too adjust it correctly: 14mm is very short, probably forks from a much larger frame that have been cut down.

Cheers for the suggestion, had totally forgot i could just get the forks rethreaded futher down. They are the original forks but for some reason have been cut slightIy before i bought the frame and forks. Was thinking a headset with 44 or 45mm stack would be fine though, 30mm space remaining and 14mm thread? dont mind getting another headset really as have a few frames needing headsets.

Top cup is at the end of fork thread in this image. Would a higher stack headset solve this problem? Generally does the stack height reffer to the size of the cups changing in height or is it more bolts and spacers above the cups ect. As maybe im over thinking it but im going to need a headset with a large bottom cup in order the keep the end of the forks thread as close to the headtube as possible. Would prefer not to get forks rethreaded to be honest.

Stack height refers to the total height of all the components of the headset. In your case you need some spacers to fill the gap between the top threaded race and the locknut, enough to allow it to be tightened without the top rim pressing on the steerer tube edge.

The top threaded race has reached the end of the thread on the forks so adding spacers would not cause that part to sit any lower.

The top threaded race has reached the end of the thread on the forks so adding spacers would not cause that part to sit any lower.

Edit: apologies, just read your post correctly. You need to tap a longer thread on the forks. AFAIK there's no way to add spacers below the headtube and fork crown race always sits tight down on the fork.

That's a big gap, which I can't see any headset coping with.

Short answer: you need to get the threads cut further down the forks.

Presumably the forks were originally in a frame with a much larger headtube.

It's a very straightforward job and cheaper than a new headset: just do it! :)