Brilliant, Andre. Have you thought of writing as a career!?  🤣

I'm curious to know if a used Brooks saddle have to be replaced by a new one..

If yes, how can we know ?

There's a tensioning bolt under the nose of the Brooks saddle. You take a one-eighth turn on it when the saddle starts looking hollow (the proper English is swaybacked -- don't ask me why: English isn't my first language, by half a dozen or so, so I would have said that if we have to have a horsey metaphor it should be lordosis, an equine spine symptom). In your case maybe a quarter-turn. When you've used up all the thread on adjustment bolt, you take the bolt to a welder and ask him to weld on a longer piece of threaded rod, same diameter and thread count per inch. If you're worried about the appearance of your clearly neglected saddle, buy some neat foot oil from your local saddlery (more £$%^&* horses), pour the contents of the can into a baking dish or a bowl large enough to take the saddle and soak first the top and then bottom in the neat foot oil, 10-20 minutes per side. You do that only once, then a thin layer of Proofide once a year only on top. After the short soak in neat foot oil lay the saddle aside for a few days to dry out a bit, then polish only the top with a soft cloth. Tension with your longer bolt and you're good to go for several more years.

A Brooks saddle is like a Catholic wife, you marry it for life, no divorce.

I'm curious to know if a used Brooks saddle have to be replaced by a new one..

If yes, how can we know ?






Thanks in advance

You'll know when the one you have gets uncomfortable.

Except it's likely a boiled-frog thing. It might be hard to remember how much more comfortable the saddle was when in better repair.

When I bought my Mercury, I fitted an ancient Brooks Professional that I had acquired from a bike purchased used 40 years earlier. I'd revived it with a soak in neatsfoot oil and had used it happily enough on several multi-day tours. I had preferred it to various plastic saddles I'd tried.

With the Mercury purchase I was in the saddle much more frequently and for longer periods. I started to wonder whether a new B17 might be better. Took me a while to male the jump because I'd heard the horror stories about the discomfort of a new Brooks and the need to accommodate that for a thousand miles or more while it broke in. If it broke in.

Bit the bullet and on went a standard B17. First ride it proved exactly as comfortable as the ancient Professional it replaced, and hurt in just the same places.

It's now been under me for a couple of thousand miles (guesswork as I don't use a cyclometer) and it's fabulous. Way better than the old one, which is the point of this anecdote.

It's a real pleasure setting off on a ride and feeling the comfort of the broken-in Brooks underneath me. For the next couple of hours I don't even think about it. At that point if I've not been off the bike or much out of the saddle I may want to stand on the pedals for a bit of relief. I'll only need a few seconds.

Not sure I understand all of that…..but the basic problem with the longer biplane fork for me was that it raised the bottom bracket height too much.  The alternative 40mm shorter Thorn fork I now use allows me to have the correct pedal - seat distance and still be able to get a foot safely down when stopping.  Essential on sloping ground and when carrying luggage.  I am sure both fork types are well strong enough for my riding speeds and style!

Forks are measured crown race to axle (C>A) that's the only length that effects geometry, it makes no difference how much of that is crown and how much blade.  I think there must have been some misunderstanding with your bike, I doubt Thorn has ever offered forks with a 40mm difference intended for the same frame. A twin plate crown fork may need to be slightly longer to maintain the same tyre clearance, a few mm, but as this link shows they don't take up much more room than any other design.
https://www.framebuilding.com/NEWPARTSPAGES/Cast%20Fork%20Crowns.htm

I think their present use is largely aesthetic, they are measurably stiffer, but not as stiff as a unicrown and it's questionably how much benefit is derived from any extra stiffness beyond what's required.  They were popular at one time because frame builders could make their own rather than buying in cast crowns, there was also the idea that they could be used with lighter blades to add compliance. I think it may also be possible to weld the blades in place rather than braze them, which might explain their popularity with Thorn's frame builders.

I've got a barely-used C17 but know people who are happy with them. Those people weigh somewhat more than my 64kg / 142lb and I think that's a factor. Few saddles have versions to cater for different rider wights.