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B17 rail breakage and Thudbuster

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dsim:
Hi everyone!

I've been using a B17 with a Thudbuster ST G4 for a while now. I got the Thudbuster with the primary aim of protecting my saddle rails.

A few days ago the left rail broke just behind the clamp on my B17 and Brooks are going to repair it.

I'm a bit worried that it could happen again when I'm in the middle of nowhere. Looking at where it was clamped, it was clamped a bit further forward (saddle pushed a bit further back) than centre, where I ideally would have put it. I wonder if I clamped it like that in a hurry a while ago.

I put a C17 on it while the B17 is being repaired, and I noticed that it wasn't possible to ensure the two clamps were uniformly engaged, with diagonal opposite sides of the rails not sitting quite right - e.g. one would sit flush, and the diagonal opposite wouldn't, then pushing the higher side down would result in the other going up again.

I wonder if the B17 was clamped not quite evenly which could be another potential contributing factor to the rail break.

I got a replacement clamp kit a while back so I was able to swap some parts. All four corners now sit flush on the clamps, both top and bottom. I'm hoping that this has fixed the issue!

If it hasn't, then I'm attracted to bring my C17 with me on my world tour because I can carry a replacement rail and it only needs a Torx 25(?) which I'll have with me. However, I much prefer the B17 to the C17, both for sitting comfort and the surface smoothness (I don't ride in bibshorts).

Alternatively, would a suspension saddle (e.g. a Brooks Flyer) be more suitable than the Thudbuster? Or is it possible to use both? I think that's probably a bit overkill though and I'm not sure if a sprung saddle can even protect the rail.

Does anyone have any recommendations to minimise the risk of a rail breakage? I really don't want to get stuck in the middle of nowhere and no saddle. I'm not going to carry a spare one.

Danneaux:
I'm sorry to hear of your recent saddle rail breakage. I've broken a number of B.17 saddle rails in a short period back when they were improperly chromed and were embrittled by hydrogen as a result of the process. I've not yet broken one with black powdercoated rails. I used mine with SR LaPrade seatposts, known for fully and evenly supporting saddle rails. I repaired them all myself, transferring each leather cover to a new frame, re-riveting the lot together. It isn't difficult.

It is important to use a seat clamp that is smooth where it contacts the rails and contacts and supports them evenly. Avoid the "rail biter" types for maximum rail longevity.

I have two bikes equipped with B.17s and Thudbuster LT (Long Travel) seatposts; two more have B.17s paired with Thudbuster ST (Short Travel) seatposts. These are not the current models, all dating from 2012, but the combination has given me no trouble to date. I did have a faulty LT pivot that drove me crazy with a clicking sound despite taking all measures to correct it. Cane Creek/Thudbuster went over my checklist, then kindly dispatched a pivot bushing and installation tool free of charge; appreciated.

I love my Thudbuster/Brooks B17 pairings and find the combination of the tensioned leather cover and the Thudbuster were "enough" for my needs. I can offer one tip that may aid comfort. I prefer a 45° back angle. I found this was not enough to adequately depress the elastomers in that position because there was not enough weight on my bottom. I subbed the next-lighted elastomer in each case and found the comfort and action I desired with no risk of bottoming-out the available travel and no "pogo-stick" effect, either. If you don't have "enough" cushioning, you might try the same. I don't see any advantage to combining a suspended saddle with a Thudbuster. Oh! One more tip: I found with my preferred back angle, it helped to move my saddle nose 4-5mm forward compared to where it would be placed on a rigid post. This allows for initial preload (i.e. settling under your body weight while seated) to place you in the same position behind the bottom bracket.

If I were going to use a Thudbuster for a RTW tour, I would toss in a pivot replacement/service kit and a spare elastomer -- puck for my ST, elastomer stack and retention bolt (they've been known to break) for my LT. These are all wear items in constant motion, are lightweight and don't take up a lot of space in your toolbag. Don't forget to oil the bushings occasionally. I'd also suggest fitting the optional Thudglove thin neoprene cover to shield the pivots from dust and moisture to extend service intervals and lifespan. Otherwise, I think you'll get along fine. I find myself less tired at the end of long randonneuring days on chipseal with the STs and the LTs solved the shock-induced headaches I got hammering my Enduro-Allroad and Nomad Mk2 on roughly graveled logging roads. With the LT, these heavy-duty bikes ride as nicely unladen as they do with an expeditionary load, where the frame absorbs more road shock.

Hopefully helpful; best, Dan.

martinf:
I've used B17 saddles (steel rail and titanium rail versions) for several decades and about 127,000 kms total. Mainly on drop handlebar bikes and Bromptons.

No breakages in normal use, but I did scrap two after crashes bent the saddle frames and damaged the leather tops.

And on the first one that I bought in 1977,  the leather top is very worn now with over 46,000 kms of use, so I put it on a bike I don't use much.

________________________________________________

I also use or have used various sprung Brooks saddles, mainly on MTB style and utility bikes with flat bars, where my riding position is often more upright. Again, several decades of use and about 115,000 kms total.

I have never had a rail breakage on any of these, but on my most-used saddle, an old B66 Champion with twin rails and the softer springs fitted in the late 1970's, I did have part of the nose assembly break a few years ago, probably at about the 60,000 kms mark while using the bike for off-road survey work (roughly equivalant to moderate mountain biking). I found a compatible single rail and nose assembly (called a "cradle" IIRC) and transferred the saddle top and springs to keep this saddle in use, it is now past 68,000 kms. The saddle top is discolored, but compared to my oldest B17 it doesn't seem very worn, either the leather is thicker or the B17 suffered more wear when I rode a lot in jeans before I started buying specific cycling shorts.

Andyb1:
My experience is very limited compared with what is written above but a few thoughts.

1.  The load on the seat rails will depend on quite a few factors - eg rider weight and how the rider uses the seat (I have seen some crash down hard on it).  Factors like rear tyre pressures will effect the shock loading.  So a heavy rider with a softer rear tyre who is more gentle on the seat may never have a problem while a lighter rider with high pressure rear tyres who bounces on the seat may damage it.

2.  I am using a B17 on a bike that previously I had a sprung Brooks Conquest on.   I want to ride in India again later this year and am trying out different options.  The Conquest does take out some road shocks so is more comfortable, but it is heavier and early on I had a spring fail.   Also, I have had to add a locknut to the nose bolt to stop it loosening due to the movement of the saddle.   The B17 is a simpler design and is perhaps more robust?   And over a rougher road I simply put less weight on the saddle - while with the Conquest I can more rely on the springs.

3.  The B17 will carry a saddlebag - the Conquest being sprung has no saddlebag buckles.

4.  A sprung saddle needs a shorter seat stem position by an inch or so.

dsim:
Thanks for the replies all.

I've decided that since I'm not comfortable with a Brooks B17 due to the risk of rail breakage while far from a bike shop as well as with a C17 due to the non-leather surface, I have now ordered a Gilles Berthoud Aspin saddle since it has user changeable rails, rear plate, and nose.

I'm also going to stop using a saddlebag, as although I only ever once had more than a kilo or so if weight on it, it doesn't help the rail and will change the effect of the Thudbuster.

I currently weigh quite a big more than I used to - about 112kg - so that won't help either.

I'm not sure if I am harsh with my saddle or not, but I'll try to be more aware of how I use it. But having the ability to change my saddle rails in the field will definitely give me confidence that even if something does break I can fix it there and then.

Hopefully I won't be making a similar post in a few months time when I'm on my tour!

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