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Sprucing up an old road bike (maybe late 90's) that takes a 1" aheadset.
Replacing the headset, removed old cups etc, but the new cups slide straight in with little/no effort - quite literally slid in by hand. My only guess is that the last headset cups were a fraction of a mm larger.
Never had this before, so good to know how much of an issue this is?
My thought is that there's no inherent danger in the short term, but the possibilty of cups rotating in the frame could cause damage/wear to head tube.
Any thoughts? Cheers
Red Loctite (641?) Is used for retaining bearings and races if they're a bit loose.
1) try some alternative brands of headset. They can all vary minutely.
2) Use bearing-fit (posh threadlock) to glue the things in.
3) Chris King used to do oversize and/or deep insertion headsets to order. You'll pay for it though!
I've used option 2 in the past with no ill effects.
Thanks both, will try some loctite, seems there's 641 and 638 to choose from.
I would try other headsets, but that could get pretty costly quickly, particularly as there's not a huge selection of 1" headsets.
No experience of either 641 or 638, but from the look of it 638 is going to be stronger, but might be too permanent.
I used 641 in a loose headset. Fitted in 2012, not heard a peep out of it since. I've plenty, but not thousands of miles a year or anything. and it's a Chris King headset. Steel frame, so applying heat won't be an issue to help break the bond if /when I need to get the top cup out.
I've got a carbon frame with a similar issue. No got any further with that one. Cups went in with expected resistance, but I get a cracking/knocking noise under hard loads. Might be the stem, headset, fork steerer... ? Checked and retightened everything, bearing retainer might be the next thing to try. Apparently you need an activator for to it bond to the fancy plastic, and applying heat is a bit more of an issue.
1" headset were not quite standard, the most common would be ISO which has a 30.2mm headset cup. JIS and Raleigh were 30.0mm, and various other less common sizes.
Have you checked the crown race? ISO is 26.4mm, JIS 27.0mm.
We used to ream JIS frames to IS standard and cut the fork crown race seat to fit better headsets to some bikes, occasionally open up a crown race ID on the lathe. You used to sometimes see some knurled forks or headset cups to increase the OD, the bodge way was to centre punch the cup OD or fork crown to create a raised surface for an interference fit (on steel parts)
Sheldon's site has a size list;
https://www.sheldonbrown.com/cribsheet-headsets.html
Thanks for that info bigyan. Headset is an FSA Orbit X (1") looking again at the spec drawings on the FSA website FSA Orbit pdf and the outside cup size is oddly listed as both 30 and 30.2 (+/- 0.1) which seems strange, surely it should just be one or the other?
The crown race is stated as 26.4mm - which should make the whole thing ISO. So it's either a tolerance issue or it's actually 30mm cups...annoyingly can't find my calipers anywhere!
The crown race is stated as 26.4mm – which should make the whole thing ISO. So it’s either a tolerance issue or it’s actually 30mm cups…annoyingly can’t find my calipers anywhere!
Just stick some bearing retainer in... if nothing else its peace of mind.
It's quite possibly ovalised anyway.
It’s quite possibly ovalised anyway
Yep, that probably is the case.
Just frustrating that FSA list the cup size as both 30 and 30.2 - without that being on the diagram I wouldn't be doubting the headset.
I had this with a second hand Kona frame three years ago. Cups rotating within the headtube during the course of a ride, they were that loose. I just glued them in with some Devcon 2 ton epoxy that I had lying around from another job (glueing a shim into a cracked seat tube to reinforce it after drilling holes to stop further crack propagation). I'm still riding the Kona thousands of miles later, the cups have never budged.
Just frustrating that FSA list the cup size as both 30 and 30.2 – without that being on the diagram I wouldn’t be doubting the headset.
Given the manufacturing quality of FSA its probably both... whatever going for the extra security of bearing retainer will be less stress. TBH never put a Orbit onto a bike... I usually use them until they need a bearing change and just swap cups over - not worth the 37 deg angle on a poor quality headset IMHO as you just pay for expensive and harder to source bearings often so I swap for either a decent one or something cheap 45/45. (Brand X or NP)
The old vintage steel frame DJ had the same problem it would fall out without holding it in ... brand-x headset and bearing retainer and it's been fine.