Thorn Cycles Forum
Technical => General Technical => Topic started by: Matt2matt2002 on January 22, 2013, 07:20:03 pm
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I am thinking of splashing out on a Brooks.
I have consulted their web site but cannot find and answer to this question.
Is it possible to make a 'bottom' impression and send it to Brooks for their opinion?
I know this sounds a bit suspect but the idea rings a bell with me.
Thoughts folks please
Matt
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You will need to post a pic of your impression on this website for us to make an informed decision Matt.
Dan should be able to help you out with how to post wide angle photos........
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You will need to post a pic of your impression on this website for us to make an informed decision Matt.
Dan should be able to help you out with how to post wide angle photos...
Ah, Ian...Ian. I can help with posting photos, but I have my limits as to what kind... :o ::) :D
Is it possible to make a 'bottom' impression and send it to Brooks for their opinion?
Well, Matt...I suppose one could, though I've never heard of it being necessary.
Generally, it isn't too hard to pick a Brooks that will result in a good fit that will prove comfortable over time.
I think you'll be in pretty good shape if you...
1) first select a Brooks suited to the kind of riding you do most (Brooks categorize their offerings by use on their website) and your preferred position (bent well over as on drops, atop the brake hoods/equivalent, or bolt upright)...
2) then check to make sure your sit-bones will sit comfortably so you aren't on the metal flange at the rear of the saddle. I've met a very few people who can tolerate sitting on the flange, but the vast majority of those I've polled are happier sitting on the leather portion just ahead. The flange wraps around the sides and the saddle cover is slightly convex, so your chances for comfort and success increase if you're sitting on relatively flat leather.
The ischial tuberosities (sit bones) tend to flare a bit and become effectively wider as the pelvis is rotated rearward (i.e. when sitting more upright). Bending over a fair ways (as when on the drops), one can more comfortably use a narrower saddle than when sitting more upright.
I learned my lesson on my first all-leather saddle -- a gorgeous Fujita Pro with water buffalo cover a full quarter-inch thick and about as wide as a B.17 Narrow. In my favored touring position atop the brake hoods, it proved too narrow and I sat squarely on the metal flange where it curved 'round the rear of the saddle. It caused all sorts of problems culminating in a saddle sore the size of a silver dollar that had to be lanced and drained. Sold it on to my then-neighbor who only rode the drops and he was happy as could be. For use with my preferred riding-on-brake-hoods back position, the B.17 Standard has worked well for me.
I hope this helps.
All the best,
Dan.
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You will need to post a pic of your impression on this website for us to make an informed decision Matt.
Dan should be able to help you out with how to post wide angle photos........
Ok I can take a joke, but I really do recall reading something about sizing and impressions. Guess it could have been a hoax but given the cost of the saddles I would have thought there would be some sense in having some kind of measurement system.
Maybe I'll ask my pal, Ben Dover?
;)
Thanx Dan. Always an oasis of sense.
Matt
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;D ;D ;D very good .
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...I really do recall reading something about sizing and impressions.
I think this is what you have in mind, Matt:
http://www.thorncycles.co.uk/forums/index.php?topic=4965.msg31333#msg31333...given the cost of the saddles I would have thought there would be some sense in having some kind of measurement system.
Agreed, there probably should be a Brooks Official Measurement System™...but there isn't, so far as I know.
Here's what I did, all details included...
I stood in my underpants and bent over at the same angle as I ride. Holding a ruler in one hand, I felt around till I found the rounded, bony head of my left ischial tuberosity (sit-bone) and pressed that end of the ruler against it with one hand. I then felt around with the other hand till I found the bump on that side and put a finger on the ruler there. I kept 'hold of the ruler and looked to see how many millimeters it was to the center of my finger and wrote the number down. I repeated the exercise a few times and was amazed at how consistent the results were.
I then transferred the measurement to a piece of cut-to-size index card I took with me to the bike store.
Placing the card on the display saddles, I could see exactly where my sit-bones would be when sitting on the saddle (remember, I took the measurements in the position/back angle I usually ride). This made it easy to see which saddles would work for me and which would not. I avoided the saddles where I would be sitting on a "corner" of the leather or atop a metal flange. As it happened, a Brooks B.17 was ideal for my needs, just as predicted by Brooks for that section of their offerings.
I hope this will help, Matt. Yes, Brooks saddles are expensive, and a mistake is disappointing and costly. Try the above, and then put the little paper card on your present saddle. It really does help when evaluating a Brooks. Any questions, give a shout.
Oh! One last thing...For many years, Brooks saddles were scarce in my part of the Yew Essay. Most were kept stored in sun-drenched window display cases and had all the compliance of cast iron. I hefted a few and was put off for many years. I was stunned when I sent away for my first one and it arrived feeling about as compliant as one of my leather belts. Hey! This could work! (and it did). So when selecting a Brooks saddle, try to get one that at least *feels* compliant to some degree when holding it...and avoid those that have been sun-baked in display cases, sometimes for a matter of years.
All the best,
Dan.
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Thanks Dan & co.
I am now at the stage of checking on ebay for secondhand Brooks
One caught my eye but has a small scuff at the rear side
http://www.ebay.co.uk/itm/261160609479?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649
Any thoughts as to potential further damage progressing into a split and also on a possible repair or at least a cosmetic cover up?
I guess scuffs are common?
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I know that Brooks saddle appear expensive but I would, from a bargain hunters point of view, feel are one of the areas worth buying new or atleast unused. A brooks saddle breaking in is much better done by the owner rather than the pre-owner. It is very difficult to tell from photos and wear if the saddle will be broken in or not and if it is broken in if it will be comfotably broken in for you.
I would be very surprised if you do not find a b17 comfortable. I prefer a b17 narrow but still find the standard b17 more comfortable but less comforting if that makes any sense at all.
I would also comment that brooks sadles seem to fetch an inordinate resale value which also goes against any sense in buying second hand.
Andy
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I know that Brooks saddle appear expensive but I would, from a bargain hunters point of view, feel are one of the areas worth buying new or atleast unused. A brooks saddle breaking in is much better done by the owner rather than the pre-owner. It is very difficult to tell from photos and wear if the saddle will be broken in or not and if it is broken in if it will be comfotably broken in for you.
I would be very surprised if you do not find a b17 comfortable. I prefer a b17 narrow but still find the standard b17 more comfortable but less comforting if that makes any sense at all.
I would also comment that brooks sadles seem to fetch an inordinate resale value which also goes against any sense in buying second hand.
Andy
Yes, that's spot on Andy. A few scuffs and scrapes are not a problem but Brooks work by being personally sculpted to your shape. If someone else has begun this journey it might not be possible to get it perfect. Imagine buying a pair of leather shoes, second hand would feel very odd at first. I am annoyed at the price hike over the last few years as it has nothing to do with production costs and everything to do with market placement, but something that lasts 10 years or more is still value for money.
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Hi Matt!
Looking closely at the auction photos in the link you provided, I don't see anything in this sort of scuff that would morph into a larger issue down the road. An outright tear or cracks radiating from the rivets, yes, but impact damage...no. It is possible for impact damage to crack the rear flange, but it generally doesn't hurt the leather much beyond cosmetic damage.
I would suggest avoiding the chrome-railed Brooks saddles, especially if buying used. Though a rare problem across the mass of saddles produced, they can be more subject to breakage and a small number do break outright and without warning. Some of the rails were not sufficiently heat-normalized (baked at sufficiently high temps to outgas the hydrogen that goes into solution: http://en.wikipedia.org/wiki/Hydrogen_embrittlement) after plating and suffer from hydrogen-embrittlement that makes the rails subject to breakage, even with a Brooks-recommended seatpost clamp (avoid the "rail-biter" kind of clamp). I've gone through a couple. The copper-plated or black powder-coated ones avoid the problem entirely. Photo/story on one of mine that broke here: http://www.thorncycles.co.uk/forums/index.php?topic=2294.msg16209#msg16209
I concur with our fellows on generally avoiding used/well broken-in, but in this case, the auction photos show no concavities have formed and the saddle does indeed look as if it had been ridden only briefly.
I've a couple used Brooks B.17s in very good condition I will be putting in eBay (people really like the ones I've re-riveted with the Brooks Pro's larger hammered copper rivets in place of the B.17 Standard's plated sheet-steel rivets that can rust) -- because I prefer them largely unbroken-in*. People buy them 'cos they don't want to break them in themselves! Hmm...Dan's Saddle Break-In Service™. The trouble is -- just as others observed above -- though lightly broken-in, these saddles reflect where my sit-bones go, those dents might not match someone else's and worse -- also as mentioned -- the existing hollows can "guide" the next person's sit-bones rather than forming to them, leading to a squirmy, uncomfortable experience. Very much indeed like trying to walk in someone else's shoes.
I've had a number of B.17 Standard saddles, and (so long as they haven't been sun-baked for ages in a shop window display case) have always found them comfortable from the get-go and fully "broken-in" to my purposes within about 300 miles. All I do to treat them is place an initial light coat of Proofide on the top and another on the bottom and let it sit overnight in a warm room. Next morning before riding, I polish off all the excess on top with a soft cotton towel, then ride. After about the third ride, I very lightly recoat the top again and then polish it off after a day. That's it for the Proofide; overdoing it can lead to premature stretching. Perhaps once every 18 months or so, I'll re-apply the lightest possible coat...just a thin smear to keep the saddle "fed". Of course, I cover the saddle in rain so it is never wet or soaked, and that helps extend saddle life greatly. My former neighbor used to de-tension old, used Brooks and Ideale saddles and then re-form them with wads of newspaper and old toe straps on drying after soaking them overnight in a bucket of water. He was happy with the result and they looked much better than I would have thought possible after such treatment.
*The reason I replace my saddles when they have "broken-in too much" is I find the center ridge that sometimes develops is painful to my tender bits; put delicately, it causes some abrasions and it is this downside that caused Jobst Brandt to label tensioned leather saddles as um, "hatchets"; some (not all) do become rather pointed along the midline axis. Tightening the tension bolt makes it worse. I've looked at a lot of saddles and this doesn't happen to every person, nor with every saddle. A Brooks is handmade from natural products (leather) and cuts vary in thickness and the amount of scar tissue incurred by the animal as well as the tanning process. I had one saddle with a hefty barb-wire scar that broke-in a bit diagonally, since that scar was less elastic. I had one saddle that was way, way too slack for my needs and was essentially worn out for my purposes in only 300 miles. It was a thin cut and just too elastic; the fellow I sold it on to thought he'd found Brooks Nirvana -- most comfortable one he'd ever tried and he won't give it up, old though it now is. I also own a beautiful honey B.17 Champion Special that is so thick and resistant I've not managed to put a bottom-dent in it yet; almost too much of a good thing!
The point is, people vary and so do the saddles, by cut of leather, but how they're wet-stamped and formed, but how evenly they're riveted (a crooked saddle causes me back problems every time). This is why I prefer to either hand-select my Brooks saddles or get them from a source with generous return privileges so I can return ones that don't suit after my own hand inspection. An acquaintance of mine, Bill Laine, runs Wallingford Bike Parts down in N'Orlins (as folks there say it; I know him from his Seattle days years ago and introduced him to Gilles Berthoud's product line; Bill is now the US distributor for GB and they became friends). He's a nice fellow, yes, but his is the only shop I know that allows a 6-month unconditional guarantee on all new Brooks saddles he sells. It is a remarkable offer. Like Thorn, he is basically self-insuring and has enough happy customers to make up for the small number of returns (which he also resells at good prices without the return privilege). That should tell you something about the success rate of Brooks saddles for the bulk of customers. See: http://www.wallbike.com/brand/brooks With the cost of outgoing and return shipping, it makes far more sense for UK and European buyers to purchase closer to home, but Bill's policy illustrates generally high satisfaction for those choosing a Brooks saddle.
Probably the best deal in the world on Brooks saddles comes from Thorn with the purchase of a new bicycle. Buy a saddle, get a Thorn for free! Well, not quite, but Thorn's bulk-purchase prices and passing on their OEM discount is a tremendous opportunity for anyone thinking of trying a Brooks. At the prices offered, if it doesn't work, you'll never lose money on the deal. A most "powaful" (yes, Andre, I remember the RBT days and your unforgettable recounting of an interview with Idi) incentive for a Thorn!
Hope this helps, Matt. I really don't think you'll have a problem after splashing out for a Brooks, particularly if you choose a model suited for your style of riding, get the setup/angle right, and treat it appropriately to initially soften and feed the leather by some means or other (Andre is a proponent of the Neetsfoot method, I favor Proofide, Lon Haldeman favored 10W-40 motor oil; like the helmet issue, whatever works for you).
Best,
Dan. (B.17 Connoisseur)
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When I bought my Raven from Andy he kindly threw in a second hand B17.
It fits me like a glove, although I don't usually wear them there!
A great saddle but the small Brooks badge on the rear is fading and coming away.
I like the look; well worn and rugged like me. But I think it will fall off soon.
Is it a glue job or a rivet job? It is so worn that I don't think rivets will hold it.
Advice sought folks.
Matt
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Matt,
Hardware stores will often have small rivets you can install by clinching yourself. I generally prefer the copper ones, but the steel ones cut to flare on impact will work as well.
Because Brooks saddles are handmade, there can be some slight variation in where the badges are affixed. Some badges are set opposite the rear cantle plate (the flange that joins the rails, to which the cover is riveted), so the back side of the leather is often not directly accessible. If you can look under the rear of the saddle -- and if your badge rivets are exposed -- you can replace the missing rivet with a small machine screw (bolt) and nut, using a flat washer as a backing plate. Or (even better), insert a new rivet and clinch it on the backside so things are good as new and look original.
Glues don't generally work too well to affix metal to leather, though it can be done after a fashion; the Brooks leather is pretty thick and stiff and well-supported in that area, so a fairly thick and viscous glue or contact cement might work. If you decide to go that route, I would suggest McNett's SeamGrip, often used to seal tents and seams in outdoors gear, or ShoeGoo, a product used to repair shoe soles (Barge contact cement is more of a contact cement and likely won't hold in this application). Do be aware, these products contain Toluene and the fumes are extremely toxic so should be used outdoors or with good ventilation. If any squishes out, it is bound to be unsightly and should be wiped away quickly before it sets. I would avoid trying to glue the badge for those reasons.
Brooks do offer a repair service...depending on circumstances. As they say, a repair is sometimes not possible (or economical, I'd add): http://www.brooksengland.com/getting-in-touch/contact-forms/repair-enquiry/
I've re-riveted a number of Brooks saddles, swapping the small chrome-plated steel rivets on B.17 Standards for Brooks' larger, solid copper rivets used on other saddles in the range (Why? The larger copper rivets looked prettier to my eye and some of the earlier steel rivets were very rust-prone and have been greatly improved in recent years). The results were always good, and I made sure the badge rivets were properly clinched while the cover was off.
I have seen loose badges saved with a bit of copper wire wrapped through the holes and then twisted 'round on the backside. A bike-racked example I noticed recently used one zip tie going through into the head of another, the excess trimmed off. And...I've seen a few where the owners gave up and tried twisting the badge free of the remaining rivet, usually with little success. There seems to be an unwritten law the remaining rivet of a pair will cling like grim death and refuse to let go. Yanking and rick-wracking the badge till it eventually fatigues and breaks leaves a sharp edge and invariably damages the leather. Better to try the wire than that!
Hope this helps.
Best,
Dan. (...who thinks it sometimes takes a bodge to save a badge)
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Many thanks Dan.
I did see a badge for sale on UK eBay a few months ago. I will keep an eye out for one and then take the plunge one way or another. As I said, I don't think it is re rivetable. If I get a chance I will post a snap shot of the present situation.
Matt
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Some Brooks saddles are said to be more comfortable out of the box than others, for instance the B73, which is of medium width and has coil springs at all three corners. I bought one for an experiment when SJS had a half price sale several years ago. You'll have to prise it out of my dead fingers to get it. But I think myth of the Brooks saddle wearing-in is mostly a myth. True, some have after much abuse gained slight indentations where their owner's sit bones touch them, and truly abominably maltreated Brooks saddles can appear swaybacked, like any other overstretched leather. But my B73 was comfortable right from the get-on and go and, if it seems marginally more comfortable, has improved only through familiarity rather than any perceptible softening.
Late this afternoon, settling in for the first long ride of the year, I thought about the saddle while on the bike for the first time in a few years, simply because it is currently under discussion on the forum, moved 3/8 of an inch, found my sweet spot from last year, and soon forgot about it as a stupid woman in an SUV too big for her driving skills took up impatient position within arm's reach of my rear mudflap.
Personally, I think that if within fifteen minutes you can't forget what you're sitting on, you want to send the new Brooks back and ask for a different one; usually you need a wider one for any of a variety of reasons, the main one being that the narrowest Brooks saddles, like the B17, are built for roadies who hardly touch their saddles as they try for the iconic flat back, while the progressively wider Brooks are intended for those pedaling from a progressively more upright posture. I've never believed in the B17 as a suitable saddle for loaded tourers. Admittedly, many undoubtedly loaded tourers swear by them, but that's probably the comfort of the familiar; the suspicion remains that if those tourers came to Brooks saddles fresh, rather than via a history as a roadie, and without the baggage of the the drop bars, even those who want to build a shrine to the B17 would choose something substantially wider from the Brooks catalogue.
Andre Jute
Iconoclast
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Hi Dan,
Like the idea of swapping out the silver rivets to brass type on my Black Brooks B17 saddle can you give some instructions on how to do this and where can you get the large brass rivets (live in the UK)
Thanks
Alastair.
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...can you give some instructions on how to do this...
Hi Alastair!
Sure can! I'll start a separate topic on it with full links. I'm 8 hours behind you and it's after midnight here, so I'm headed to bed soon.
My technique is a little different from others shown on the 'Net and has been successful for every saddle I've tried it on. It is not difficult, and greatly minimizes the possibility of bruised leather and damaged rails/cantle plate.
I feel sure I have some photos from the last go-'round and will see if I can find them to go with the procedure.
Best,
Dan. (...who has stayed up to watch some major breaking news on television)
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...can you give some instructions on how to do this and where can you get...
Alastair,
I have posted a tutorial and suppliers list here: http://www.thorncycles.co.uk/forums/index.php?topic=6369.0
Best,
Dan.
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Hello Matt,
Did you get your brooks in the end?
I have been instructed to stay off the bike for a minimum of two months because of damaged ischial tuberosities (sit bones)
This was probably started on my first trip to Istanbul on a used brooks sprung saddle. For quite a while I hadn't realised that the spring needed adjusting and the saddle was actually bouncing off the metal. Add that to the last few years and I've been in quite a bit of pain for the last part of my trip. I have now been told to sit on a rubber ring at home and stay off the bike :(
Is there a thread with alternatives to Brooks? I found not only my sit bones got a battering but also the insides of my thighs rubbed a lot. I tried all sorts of adjustments but could never get it to go away.
For my next trip I'm considering the following.
Different saddle to the standard Brooks B??47??
Drop bars or different bars to give me a less upright position.
Thudbuster seatpost.
Has anyone got any experience with any of these???
what better way to avoid the post tour blues than planning the next one :)
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Hi Richie!
My combination of drop handlebars for a 45° back angle*, a Brooks B.17 Standard and a Thudbuster LT suspension seatpost have resulted in unqualified success on my own Nomad. You can see photos and a discussion of the LT and ST 'post options in my "Danneaux's Nomad" gallery entry.
Related threads here:
http://thorncyclesforum.co.uk/index.php?topic=7089.0
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49113#msg49113
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49115#msg49115
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49125#msg49125
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49147#msg49147
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49255#msg49255
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49269#msg49269
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49273#msg49273
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49567#msg49567
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49587#msg49587
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49589#msg49589
http://thorncyclesforum.co.uk/index.php?topic=4523.msg49735#msg49735
http://thorncyclesforum.co.uk/index.php?topic=4523.msg50471#msg50471
http://thorncyclesforum.co.uk/index.php?topic=4523.msg50507#msg50507
http://thorncyclesforum.co.uk/index.php?topic=4523.msg50585#msg50585
http://thorncyclesforum.co.uk/index.php?topic=4523.msg50655#msg50655
http://thorncyclesforum.co.uk/index.php?topic=4523.msg50849#msg50849
http://thorncyclesforum.co.uk/index.php?topic=4523.msg50891#msg50891
The ST worked well on-road, but was inadequate to address what I found to be a neck-snapping stiffness on the Nomad's robust frame when riding off-road and on very rough logging roads _unladen_. The LT works ideally in that case, but I am seriously considering an ST as a "someday" purchase for my primary randonneur bike and also for a second one, which doesn't get ridden so much because it has a very stiff ride on pavement. I'm not old, but the time and miles have taken a toll and I do think such pounding damage can be cumulative after a couple hundred-thousand plus miles.
For what it is worth, I think the suspension post's blunting of sharp impacts results in an easier life for the saddle leather and rails (I've broken three sets of Brooks saddle rails over the years, and transferred my old leather covers to new rails, re-riveting using Brooks' copper rivets).
Hope this helps. All condolences on your painful injury and all the best for a speedy and complete recovery soonest.
Dan.
*NOTE: To use drop handlebars and get a 45° back angle on my size 590M Nomad, I use an inverted 60mm riser stem and compact drop handlebars. No leverage, steering, or handling problems using the short stem, and it results in more of my weight being carried within the wheelbase of the bicycle. I used the same stem length on AndyBG's loaned size 587s Raven Tour with Thorn's Zoom Anatomic handlebars to produce the same fit within 1mm or so. Again, no leverage, steering, or handling problems for me on my fully loaded double European transcontinental crossing this summer. My former 560S Sherpa Mk2 used a shorter top tube and a more conventionally sized stem to achieve the same fit.
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Wow Dan I had no idea you had all of my ingredients.
I will have to look into it all.
Cheers
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The Brooks Conquest is essentially a Brooks Pro with springs, it is narrower and less likely to rub. I have Conquests on all my bikes.
Brooks has come out with some non leather saddles. If I was looking for a saddle for touring that I did not want to worry about it getting wet, I would consider it. I have not ridden on it yet, but have seen on that another person was touring on, he liked it.
I think if you lean more forward, you may need a narrower saddle.
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Cheers Mick, it's all being noted.
Does anyone per chance know the shop that will let you try out a Brooks and if not happy they give you a refund?
I saw an advert for it a few years ago and can't find it now :(
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Does anyone per chance know the shop that will let you try out a Brooks and if not happy they give you a refund?
Yep; sure do!
My friend Bill Laine at Wallingford Bicycle Works in New Orleans offers such a service over a 6-month period, as does a "saddle lending library" in New York City.
Bill can be reached here: http://www.wallbike.com/
Be aware of the added costs of international shipping each way, which will make the potentially free trial not so very free at all.I think it would be more cost-effective for customers outside the US to buy a saddle and then sell it on if it doesn't work.
All the best,
Dan.
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I think you may have solved my mystery. My addled brain was telling me it was somewhere near Oxford (UK)
Wallingford is near Oxford. I think I may have seen it online and not noticed it was in the US.
So many reasons to visit North America for a little trip at the moment. How cold is LA in December/Jan
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oh, Louisiana in January, for cycling... might be a delight!
http://www.usclimatedata.com/climate/louisiana/united-states/3188
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I am thinking of splashing out on a Brooks.
I have consulted their web site but cannot find and answer to this question.
Is it possible to make a 'bottom' impression and send it to Brooks for their opinion?
I know this sounds a bit suspect but the idea rings a bell with me.
Thoughts folks please
Matt
This first post here gives some useful tips. It suggests playdoh for making the impression but corrugated cardboard can sometimes work. Note the special calculations for Brooks.
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Jim it does indeed. 8)
So here's a different take on things...I'm thinking of getting a Brompton or a Bike Friday to do a different type of bike touring.
Would one saddle be appropriate for a foldy and my Nomad or would it wear in different places???
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Would one saddle be appropriate for a foldy and my Nomad or would it wear in different places???
Richie,
So long as your position on each (different) bike is the same, the saddle should be freely transferable. The sit-bone impressions made on one would work on the other. All my bikes are set up so I can duplicate my preferred position, and I've had no trouble transferring saddles from one to another.
However (you saw this coming, I know), if your position differs greatly from bike to bike, then yes -- the saddles will form to a specific bike.
The key here seems to be whatever affects back angle. As the pelvis rotates forward (result of a forward lean), the ischial tuberosities (sit bones) become effectively narrower. As the pelvis rotates rearward, it becomes effectively wider (as when sitting uprght). That's how saddle wear patterns are most affected.
Either of the bikes you mentioned can be made to pretty much duplicate your position on a larger-wheeled bicycle. The key question is, do you want to have the same position? If you do, then no problem switching saddles between them. If you don't (and many people seem to prefer a more upright position on small-wheeled Folders), then you'd likely want different saddles for each bike.
Where Bike Fridays are made here in my town, I was going to mention some things to keep in mind when selecting a small-wheel folder, but that is beyond the scope of this Forum, which is geared primarily toward Thorn Bicycles. Richie, you're welcome to contact me off-list if you wish to discuss the particulars of Folded touring in greater depth.
Best,
Dan.
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I ride a Thorn eXpr and an H6 Brompton, I have them set up to give as near the same very relaxed ride position as I can.
I ride a titanium B17 with a titanium seatpost on the Brompton, a Flyer (= a sprung B17) on a cro-mo seatpost on the eXpr.
Both rides are comfortable.
I simply don’t put the sprung saddle on the Brompton to save weight and folded size, but I could.
Julian.