Sorted 31/32" x 30tpi top nut for a clip type headset

[3wheeler7]

Definitely one for the old bike guys this one, has anyone got one they'll part with?
Not very common but a few manufacturers used 31/32" headsets in the 1930s/40s. I have a very lightweight path racer frameset (I think it's an FC Parkes) that came with one but I've misplaced the top nut.
I believe the one I had was octagonal but they were also made circular with knurling and peg spanner holes in the top face - possibly a Chater-Lea or BSA part. Either would do me.

 

[walkmanman]

I have lots of mixed headset bits of this type, from the eras you mention, but the thing is that I don't know if forks I have (from the same eras) would have the required threading that would match a top nut with the threading you're after, in order that I can test them. And TBH your description of the top nuts most likely to have the threading doesn't help that much. Perhaps you can find a few pics on the Internet (Velobase etc) of the headsets you're talking about so I can have something definite to search for?

 

[3wheeler7]

Hi, thanks for replying, the only pics I can find are here on Velobase

VeloBase.com - Component: Chater Lea Head clip Type

velobase.com

This is the Chater lea version, I've cropped the pics to show just the top nut.
Obviously the 31/32" nut I'm looking for will not screw on to a standard 1" fork tube.
Condition does not really matter nor does the style, I'm sure the one I've lost was a hex or octagonal nut.


The internal diameter of the thread on a 31/32" nut is 24.15mm (0.950") whereas the internal diameter of a 1" nut is 24.75mm.

 

[3wheeler7]

Still looking for a 31/32" top nut, anyone?

 

[Jonny69]

If you get stuck, the old chromed roadster style headsets have the same threading. They are the ones with integrated cups in the head tube and separate bearing races.

 

[3wheeler7]

If you get stuck, the old chromed roadster style headsets have the same threading. They are the ones with integrated cups in the head tube and separate bearing races.

Hi, yes but I can't find one which is 31/32" x 30tpi threading, I've got lots of 1" x 24tpi and 1" x 26tpi top nuts but not 31/32" x 30tpi.
The only thing I've found so far with the correct thread is a screw-on top race

 

[walkmanman]

Well it's took me an eternity, but I think I've actually found one of these top nuts for you, although I guess you may well already have sorted something by now.
If not then what I've found is a Brampton one. See here:





It definitely looks to be of the correct time period, and I've checked the threading and it won't screw onto a standard 1" threaded steerer. The threads also look to be in good condition. I noticed that the nut (as well as a top race it was zip tied to) is branded Brampton and remembered that this was also the name used by a French company manufacturing parts from roughly the same period as the British company that shared it's name. So I was a tad concerned that it could have been made by the French company which, as you're probably aware, would have French threading as this was the done thing in France at the time. Therefore I thought I should try the nut on a steerer of a Rochet frame I have from the 30s, and fortunately it didn't fit that one either So looks like it should be OK. BTW if you want the top race I'll include it gratis, although of course it would likely only be compatible if your existing headset is Brampton make and perhaps a matching model. It does look in quite nice condition though compared to the nut I've a digital caliper and can measure the internal diameter if you like.

 

[3wheeler7]

Hi, thanks for taking the time to sort through your bits. No, I haven't found one yet so I'm definitely interested in the one you have.
The inside diameter of the thread is 23.94mm on the TDC screw-on top race that I have and this screws perfectly onto the fork stem, so I'd be grateful if you would measure yours to see if it's similar and let me know the price please.
I could modify the TDC race into a top nut but it appears to be new old stock so I don't really want to destroy it.

 

[walkmanman]

OK well the inside diameter measurement I've taken is 23.91mm. It's a tad out but I guess that would just be my handling of my calipers. If you're OK with that then my asking price is £7 plus postage. Pm me and we can wrap things up.