Thorn Cycles Forum

Community => Non-Thorn Related => Topic started by: Andyb1 on September 10, 2023, 08:42:20 PM

Title: Brooks saddle nose adjusting nut
Post by: Andyb1 on September 10, 2023, 08:42:20 PM
Does anyone know the thread used on the Brooks nose adjusting nut - the one that adjusts the saddle tension?
Mine keeps slackening off and I want to add a second one as a locknut.
I guess it is a whitworth thread?
Thanks
AndyB1
Title: Re: Brooks saddle nose adjusting nut
Post by: UKTony on September 10, 2023, 09:24:58 PM

If your saddle uses this tension pin then according to SJSC who answered a similar question about this item,  the thread is M8 (see the Questions and Answers). Otherwise I’m afraid I don’t know.


https://www.sjscycles.co.uk/saddles/brooks-tension-pin-assembly-64-mm-with-nut-zinc-bmp173/
Title: Re: Brooks saddle nose adjusting nut
Post by: JohnR on September 10, 2023, 10:23:54 PM
Can you loosen the nut and apply some blue (low strength) threadlocker then retighten? 
Title: Re: Brooks saddle nose adjusting nut
Post by: Andyb1 on September 10, 2023, 10:37:53 PM
Thanks for the replies -
- the thread on mine does not look like metric, I read elsewhere it was 5/16 bsf so have ordered a couple of nuts to try.  I think later ones may be M8.
- I have tried locktite but the nut still loosens.  Maybe grease under it, or the movement of the saddle just rocks it loose?
Title: Re: Brooks saddle nose adjusting nut
Post by: j-ms on September 12, 2023, 05:04:29 PM
My tensioning nut on wife's previous B67 started  to loosen after a few years.  We were on a long tour when this became  a problem and so after struggling for a few days I simply superglued it after setting the correct tension.  It never needed to be retensioned after that because the rails both snapped about a year later (but that is a story on its own).
Title: Re: Brooks saddle nose adjusting nut
Post by: Andyb1 on September 13, 2023, 12:14:15 PM
Hi,
The nut thread is 5/16 BSF on my Conquest saddle which is about 20 years old……but the bolt part was worn so a locknut could not be used.   Anyone want a couple of 5/16 BSF plated nuts?

I have just ordered a new unit from SJS with adjuster nut, and that may be metric.

Once apart I realised why the locktite had not worked - the threads were filthy.

Thanks again for the replies.
Title: Re: Brooks saddle nose adjusting nut
Post by: Andyb1 on September 16, 2023, 09:42:15 AM
The new adjusting bolt is also 5/16 BSF threaded so I added a locknut in front of the adjusting nut.

The Conquest saddle has rear springs which will allow the saddle to rock from side to side much more than a B17, so that is maybe why it loosens?