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Brompton introducing a 12 speed

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Brompton introducing a 12 speed

Old 01-24-24, 05:38 PM
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My own view is that Brompton does provide people exactly what they want, and that explains its undeniable appeal, popularity and success. For some people, that means the smallest, quickest fold. But for many others for which the fold is a nice-to-have-but-not-necessary, brag-worthy rallying point, it provides access to a lifestyle, conspicuous consumption and to the sense of belonging to an ostensibly exclusive in-group of people in the know. Never mind, of course, that there's little exclusive about a bike of which there are now at least one million specimens. But facts have never gotten in the way of religion.

​​​​​In the Global South, it is often a trophy of the New Middle-Class, signifying that the person has arrived and can afford a luxury Western product. Not very different from Prada, Gucci, etc. There's a whole psychology to this, Brompton ain't stupid and exploit it fully, and many people are willing, happy participants in their own exploitation. Note, for example, the invitations to purchase. WTF! Conditioning, a term from psychology, was mentioned earlier, for example. The psychology of a Cult Brand has been studied and well understood for decades now. It's no mystery.

Precisely because Brompton has an invested, captive audience, it can afford to offer innovation and improvements at trickle pace and volume. For their part, the cult members put up with it gladly or grudgingly because Brompton provides other intangible but highly sought-after belonging and prestige benefits - as well as the smallest, quickest fold, of course -- that well offset what would otherwise be unacceptable technical shortcomings. This again is no mystery, and has been well studied and understood in the field of Economics. Brompton gives people exactly what they want. But it often has nothing to do with the technical merits of the bicycle per se. After all, the rational consumer turned out to not be so rational after all.

Last edited by Ron Damon; 01-25-24 at 04:25 PM.
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Old 01-25-24, 04:24 AM
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Splithub, tds101, Ron Damon, I agree with you all; Brompton trickles out innovation, and understands marketing; Regular Bromptons are premium priced, and they have special "designer" editions that are more than twice the price. Having said that:
- Premium pricing is one of the Seven Deadly Business Sins; it gives incentive for competitors to enter the market and can easily undercut the price and do so profitably. Having said that, I saw a Chinese Brompton copy, and during the pandemic when shipping costs were high, it would have cost 3/4 the price of a Brompton, with unknown frame quality and sketchy warranty at best. I told the seller that I would not consider a copy unless is was priced *at most* 1/2 the genuine article, and by the way, I do respect intellectual property, so I would check on the patent status.
- Other manufacturers also used to trickle out innovations. Until other companies tried harder to please customers, exceeding expectations, among them, Apple, who had the philosophy of making their product "insanely great".

Fortunately, Bromptons are now commonly available, didn't used to be, which is why I see craigslist ads for used ones at new prices, those folks haven't gotten the word.

I also think a company should have some control over retail pricing, not in terms of discounting, that is price fixing, but in terms of gouging markups; I read that C8 Corvettes, now in its 5th model year for that generation, are selling at 100% markup (Pricing 200% of MSRP), which is why I see them selling used for over MSRP. That's ridiculous, does nothing to help GM, just fat commisions for dealers. Many decades ago, the government prohibited the carmakers from owning dealers (which, IIRC, has been tested under Tesla), but if I was GM, I'd cut off dealers that were charging that much markup. Saturn made huge points for selling at a fair and flat ("no-haggle") price (which GM was able to enforce), and their dealers treated people well. Sorry to see them gone.

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Old 01-25-24, 05:05 AM
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Yes Brompton is using its brand name to put high price and avoid to innovate. I also would like to see Brompton doing more innovation and using more up to date components especially for the transmission, for instance P-line and T-line with a 11s or 12s cassette+derailleur instead of the 3x4s solution.

But the higher price is not only margin, costs of Brompton are also higher.

The bikes are really manufactured, not only assembled, in the UK were manpower costs are much higher and in many countries Brompton has big network of resellers that support customers and cost much more than selling only online.

Every customer has to decide if this is important for him or not and if he is willing to pay a higher price for that.
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Old 01-25-24, 09:16 AM
  #79  
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Originally Posted by Ron Damon
​​​​​In the Global South, it is often a trophy of the New Middle-Class, signifying that the person has arrived and can afford a luxury Western product.
I suggested as much a few years back and had a couple of posters (with no rebuttal from anyone else) deride the thought that a bicycle could ever be any sort of status symbol.

- as well as the smallest, quickest fold, of course --
How good is Brompton's marketing? Brompton's fold is neither the smallest nor quickest, but even folding bike enthusiasts parrot Brompton's claims.



Brompton employs the Blue Ocean Strategy in their marketing (brilliant!) They don't target the small pool of cyclists but the vast numbers of people who don't cycle and don't know anything about bikes. You see this in things like an issue of the gearing being too high. A cycling guy would say 'Either put a smaller chainwheel on the crankset or a larger sprocket on the hub.' Brompton doesn't demand their customers learn what cranksets or sprockets are or how to calculate gear inches; they say instead, 'We offer the option of 12% lower gearing.' A cycling enthusiast would point out Brompton's debunked material science claims and antiquated manufacturing techniques; their blue ocean customers will instead gush the marketing literature: 'Bromptons are hand built employing the almost lost art of torch brazing.'
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Old 01-25-24, 10:27 AM
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Originally Posted by tcs
How good is Brompton's marketing? Brompton's fold is neither the smallest nor quickest, but even folding bike enthusiasts parrot Brompton's claims.
The Brompton is the smallest widely available because Brompton has a wide network of resellers.

I know that you advocate that the Curl is slightly smaller, which is true, but for any reason, Dahon doesn't promote it and doesn't distribute it widely.

Most people doesn't know the existence of the Dahon Curl and those who know that it exists cannot buy it easily.

I never saw any bike shop selling the Curl even those I know who have other Dahon do not have the Curl, I could never see it in real, only some online store sell it with often the Curl sold out for long period of time, while I have about 20 Brompton resellers at less than 30km from where I live and as consequence there are many Brpmpton users where I live, I see people riding Bromptons daily.

BTW, to a lesser extend, the same is valid for the Birdy, much less resellers, no promotion by Riese & Müller, many Riese & Müller where I live but most of them only sell R&M ebikes, not the Birdy, only 3 or 4 sell the Birdy and have one in their showroom. Most people do not know the existence of the Birdy.
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Old 01-25-24, 11:23 AM
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Besides, the Curl requires carrying a backpack. Must less convenient.

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Old 01-25-24, 05:00 PM
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Brompton’s popularity stems from its superior frame design and its superior fold. They go together. It was able to create find a niche and survive so far against the currents of globalism. The fold is compact enough to be packed in a case that meets airline regulations without any disassembly, or even flown with it in the overhead luggage. You may think that I am biased since I own one, but that was not the case before I owned one. I had owned many folders, before. When a local bike shop became a Brompton dealership. I test drove it and was impressed with it enough to order it. At that time my employer would send me all over the country on a day’s notice. Being able to pack it quickly was a big advantage. Today I am retired and travel much less, but it remains important to me that I can take it into places that I would not be able to take the Swift or Zootr. I ride to the grocery store and it quickly transforms into a shopping cart.

I agree with those who point out that it's expensive, but so are most mainstream bikes these days. And Brompton holds it value better than most. I would also agree that Brompton is slow to innovate. That it is still around, is testimony to how well it was designed to begin with. The lack of innovation has probably made it easier for them to stock parts. My B is over years old, and I am not concerned that parts are not available. I might be if it was say a Dahon. The one area that I do agree with the critics is the ride. I am fortunate that I live in Flatlandia. Originally, my B was a 6-speed. I added a cog and made it a 9-speed. After I retired and was only riding it locally, I bought a used 2-speed wheel and made that into a 3-speed by moving the extra cog. I did this for simplicity because I was seldom shifting the IGH. Now the ride does suffer to a degree from the 349 wheels. In hindsight, it would have been better if the B had built around 355 wheels. The 6mm would have been worth it.

I do think the P and T lines are an innovative, but I wished that Brompton would do a 20-inch model. That B would be my holy grail if it could take 2-inch wide tires with fenders. Since I don’t know it they will do this, I have been looking at this https://www.aliexpress.us/item/32568...yAdapt=glo2usa The price is great, and it seems fairly well spec’d. 9-speed Sora but 1 3/8 tires and It's pretty heavy pushing 29 pounds. Still it's Chromo with fenders and rack. Shipping is included. I would worry that it might arrive here bent. Then what?
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Old 01-25-24, 06:09 PM
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Originally Posted by Jipe
Yes Brompton is using its brand name to put high price and avoid to innovate. I also would like to see Brompton doing more innovation and using more up to date components especially for the transmission, for instance P-line and T-line with a 11s or 12s cassette+derailleur instead of the 3x4s solution.

But the higher price is not only margin, costs of Brompton are also higher.

The bikes are really manufactured, not only assembled, in the UK were manpower costs are much higher and in many countries Brompton has big network of resellers that support customers and cost much more than selling only online.

Every customer has to decide if this is important for him or not and if he is willing to pay a higher price for that.
I agree. All derailleur gears would require a hub with closer flange spacing, but with that small a wheel, there is plenty of spoke angle to make a strong wheel, in fact the angle can be excessive on the non-drive side, but often that is spoked radial with the spokes exiting the inside of the flange, due to that. However, as has been noted, a super-wide-range cassette is a challenge on 406 wheels, and 349 would be more difficult, but perhaps with the inherent lower gearing of 349, a 1X cassette system would work, not needing as large a low cog.

In the 1960s, Chrysler would not make a hemi-Dart, until a dealer (in Chicago I think), successfully dropped a 426 hemi into a Dart and drove it to Highland Park MI to show Chrysler. The next year, Chrysler offered the same. My guess is, the same thing will happen with Brompton, but only if the rear dropout spacing in 135mm, otherwise it also involves a new rear triangle, a lot more difficult conversion.

I sort of agree about the retail dealers; There's a couple local Brompton dealers that don't give good support on any of the bikes they sell. However, REI is now a seller, and they do give good support. I know a Tern buyer who brought her bike to REI for service because they were more competent.
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Old 01-25-24, 07:16 PM
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Originally Posted by Winfried
Besides, the Curl requires carrying a backpack. Must less convenient.

That's the first Curl I've seen with external gearing, much less a 9 speed. All I've seen online is internal 4s. Ah, I think the D9 is new this model year. Notice what appears to be an additional derailleur arm to take up slack, with what looks like only a GS or shorter main cage. Plus it has disc brakes. Those two things mean it's most certainly not a copy of a Brompton, patent law allows improvements. The greater weight is due to the discs, and stronger fork and frame due to that, justified. I don't like the stem tilted back like that, I prefer closer to vertical, like their 20"ers, it provides increasing effective top tube length as the seat and handlebars are raised. My question is the gear range. Ah, found the specs online... gear calc indicates 26.4-67.2 gear inches, that's just a bit too tight for me, I need 21-85 minimum. 349 wheels with a derailleur has inherent limitations on the low end due to cog/derailleur clearance, and the high end due to crank/small-cog size. The same bike applied to 20"/406 wheels, would solve both, and with discs, I think would be a world-beater. EDIT: A 50/34 double would give the curl 19.5-73 gear inches. With a 9 tooth high cog, it would be 19.5-89.2 gear inches, that makes it!

OH! OH! Innovation! Notice that the front brake caliper and disc is on the drive side and caliper moved to the FRONT of the fork. This solves the problem of disc brakes pulling the axle out of the dropout (the reason for thru-axles), without needing a special caliper or the cable exiting on the bottom. I have advocated this exact thing in the past. It also means the front disc folds to the inside, protecting it when folded. EDIT: Folded view shows the front disc to the outside; The front wheel was reversed before folding, I think due to the direction the stem folds, so the stem and handlebars are on the outside. Dahon has changed their mind over time, on whether the handlebar folds to the inside or outside.

Off topic, saw while trying to find price on Curl D9: Dahon is selling a non-folding mini-velo:


Structurally, the bent down-tube doesn't make sense, a straight one for a pure triangle is better. This shape seems copied from Bike Friday's latest cargo bikes, which went from a triangle to that shape, parallel top and down tubes, so the front can telescope fore/aft to provide better fit for effective top tube length. I see no telescoping joints on the above.

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Old 01-26-24, 04:30 AM
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The front disc on the right side is I think chosen to ease the folding (same as on the Birdy) ?



The Curl has no down tube but two tubes with the rear wheel in-between.

For the tensionner arm as a derailleur cage extension, this solution was used on the Birdy 1 and Birdy 2 and proved not reliable 4chain drop when unfolding).

Again, even if the Curl D9 appeared in the Dahon online catalog, no shop seems to sell it ?
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Old 01-26-24, 04:41 AM
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Originally Posted by Jipe
The front disc on the right side is I think chosen to ease the folding (same as on the Birdy) ?
Maybe. But it sure is the perfect solution to axle pullout with discs and quick releases. On the rear, most solved this by moving the caliper to over the axle, and not aft of it, or forward of the axle inside the rear triangle. Or, converted to thru-axles, or thru-skewer a la later Trek 520.
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Old 01-26-24, 05:35 AM
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With the folding of the Curl (and Birdy and Brompton) where when the bike is folded, the front wheel come on the right side of the rear wheel, a front disc on the left side will of the font wheel hit the derailleur when both wheels are folded and it increase the folded width.
Placing the disc of the front wheel on the right side avoids this problem and reduces the folded width.
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Old 01-26-24, 11:59 PM
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Originally Posted by Jipe
With the folding of the Curl (and Birdy and Brompton) where when the bike is folded, the front wheel come on the right side of the rear wheel, a front disc on the left side will of the font wheel hit the derailleur when both wheels are folded and it increase the folded width.
Placing the disc of the front wheel on the right side avoids this problem and reduces the folded width.
Well, great design equates to a win-win on all counts.

With my early Dahon Speed (handlebar folds to inside), I'd be inspired to reverse the fork before folding, to evaluate folding with the handlebar to the outside, except with my front rack, I can't do it, the rack will hit the frame monotube. Some later Speeds have the handlebar fold to the outside:




My earlier suggestion of a 50/34 double and 9 tooth high cog, to reach sufficient gear range for my liking (with 16"/349 wheels), I realized may have a flaw, in that the rear wheel swinging forward to fold, I don't know how much problem the chain will be at the front derailleur; I think if on the big ring (proper for folding to take up chain slack), and if adjusted well, and the bottom of the derailleur cage is flat, so as not to tilt the chain outboard or inboard, I think it may work fine, the chain wrapping onto the big ring after exiting the derailleur aft.

Ahh... very relevant quote from Bikepacking.com in review of Bike Friday All-Packa (which also has a swinging rear triangle to fold):
The All-Packa comes in a 1x or 2x version. The 2x option is a reflection of the fact that the bike won’t accommodate the very large cassette ranges that are common nowadays on 1x drivetrains. That’s because the derailleur cage has to be relatively short to not put it completely in jeopardy. The biggest cassette gear will therefore be a 40. The one they sent me has a 42 chainring, yielding a combo that I found reasonable for loaded trips, but that for many won’t cut it going up the steepest pitches. On the other end, the 11-tooth small gear met my ambitions for going fast enough on the flats and downhills, but I could imagine some people finding it limiting. Clearly, that would get worse with a smaller chainring. A 2x therefore makes good sense. I can report, too, that having a front derailleur on one of my other Bike Fridays makes chain management when folded a little easier since the derailleur keeps the chain somewhat scooped up.

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Old 01-27-24, 04:18 AM
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The Birdy Touring has ex-factory a 52t chainring with a 9-32t cassette and a long cage derailleur (its 50x355 wheels have almost the same diameter than 28x406 wheels). Folding of the rear arm doesn't cause any problem anymore due to the Birdy 3 parallelogram tensionner around the chainring. Due to the rear swingarm geometry, on the Birdy, for the folding the chain must be placed on the smallest 9t cog.

About the folding of the Dahon of your picture, the other drawback is that when folded the chain remain exposed while on the Curl, Birdy, Brompton it is protected because sandwiched between the folded front and rear wheels.
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Old 01-27-24, 05:45 AM
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Originally Posted by Jipe
The Birdy Touring has ex-factory a 52t chainring with a 9-32t cassette and a long cage derailleur (its 50x355 wheels have almost the same diameter than 28x406 wheels). Folding of the rear arm doesn't cause any problem anymore due to the Birdy 3 parallelogram tensionner around the chainring. Due to the rear swingarm geometry, on the Birdy, for the folding the chain must be placed on the smallest 9t cog.

About the folding of the Dahon of your picture, the other drawback is that when folded the chain remain exposed while on the Curl, Birdy, Brompton it is protected because sandwiched between the folded front and rear wheels.
Oh no question that I would prefer a drive-side hinge, to put the chain between. With the derailleur all the way in on the largest cog, it sticks out from the axle nut about an inch, but, not only would I accept that additional inch in folded width, but it's not even additional, because with a left hinge, the derailleur is still sticking out an inch on the other side! The fork I think might bash on the derailleur, but a dedicated pad on the outside of the right fork leg would cushion that. Could be a more difficult problem with an IGH shiftbox there, but I think still better than said shiftbox sticking out solo to get bashed.

The Dahon current left hinge, may have to do with their magnet system on left fork and left rear droput to hold things together, which wouldn't work with the derailleur there. The magnets are strong, but one of the first things I did on my Speed is remove them both; The rear one would have blocked my lower rack mount, plus the rack is wide (designed for disc brakes), so the magnets wouldn't meet anyway. Then I removed from the front because it served no function. When I fold it, which isn't often, I just use cord or a strap to hold it folded. But yeah, I'd hinge it to the right.

Dahon needs to hire me as a consultant, I've come up with so many improvements, and *everyone* who sees my double crank setup, wants it bad. I think the Speed TR (Touring) with 3x7 or 3x8 IGH/derailleur, had a fantastic gear range, but I think didn't sell due to the IGH. It came with decent racks, nice bar ends, even a generator hub if I recall, good travel bike, but serious tourers want external gearing. It was also priced high, perhaps too close to a Bike Friday. The Formula S18 and S20 looked really nice, double crank, disc brakes, (this was around 2013, so fantastic features), but the crank was 53/39 (not as low as my 50/34 and even more duplicate gears), and, IIRC, $1500, even closer to BF territory. Jeeze they sold twice as many models back then, as high as 34, (even one with a Rohloff, belt drive, discs, and on 451s, must have been hugely expensive), but never quite on the mark for me, but could have been so easily, the right parts existed. Makes me think they don't have a serious bike-head on their design staff.

I rode my Speed 7 for 7 years before finally doing the crank conversion, had been thinking about it for years, heck, got the adaptor from Thor must have been 3-4 years prior. Best thing I ever did. Completely transformed the bike. Now I need to work on a packing scheme for checked flying, I know it can be done, just need to work the details of what container, whether disposable or not, and packing layout. Train is easy, none of that.

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Old 01-27-24, 09:46 AM
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The 3 speed IGH like the discontinued Dual Drive and the current Sturmey Archer are heavy.

The same apply for the BWR of the 12s Brompton solution: at 8.8kg almost naked (without lights, rack, pump... only mudguards and front block for a Brompton bag, meaning that in normal use, it will be above 9kg), the 12s T-line is definitely not a superlight bike anymore and doesn't justify its price, a 12s P-line that cost much less and has a stiffer frame will do the job as well.
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Old 01-27-24, 05:51 PM
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Originally Posted by Jipe
The front disc on the right side is I think chosen to ease the folding (same as on the Birdy) ?
NEW INFO!!! From Dahon site: "A single-beam front fork is stiff and strong." Did they do a monofork? Can't tell from the pic but I viewed a video online, here's a screenshot:

Yes they did. My guess is because it reduces folded width, no left fork beam to hit anything. So that's why the disc is on the right. Even more brilliant. (And I am NOT a flag-waver for Dahon, but this looks good.) That also explains the fork dropout looking more beefy, like that of a thru-axle, but I don't know if they have that or a quick-release. With a cantilevered axle, tightness of that connection is critical.

As stated previously, this bike with a 50/34 double (with same tires and cassette) would give the curl 19.5-73 gear inches. With a 9 tooth high cog (and same low of 28), it would be 19.5-89.2 gear inches, that's a winner. I don't know if you can put a 9 tooth on a standard freehub body used with the original 11-28. Assuming the seatpost is standard Dahon diameter, the seat tube should be same outside diameter as Dahon's other aluminum bikes (unless the stresses are higher?); I've done a front derailleur mount on Dahon's steel frame and it just barely worked, the aluminum frame is just slightly larger in diameter there, I think a mm, and they make an adaptor, but the fit there is critical in letting the derailleur go far enough in for the inner chainring (much more difficult than a conventional bike with a skinnier seat tube). Better than a clamped FD adaptor would be a braze-on, which I first saw on early photos of the Dahon Launch, but disappeared for production bikes.

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Old 01-27-24, 06:17 PM
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Originally Posted by Duragrouch
NEW INFO!!! From Dahon site: "A single-beam front fork is stiff and strong." Did they do a monofork? Can't tell from the pic but I viewed a video online, here's a screenshot:

Yes they did. My guess is because it reduces folded width, no left fork beam to hit anything. So that's why the disc is on the right. Even more brilliant. (And I am NOT a flag-waver for Dahon, but this looks good.) That also explains the fork dropout looking more beefy, like that of a thru-axle, but I don't know if they have that or a quick-release. With a cantilevered axle, tightness of that connection is critical.

As stated previously, this bike with a 50/34 double (with same tires and cassette) would give the curl 19.5-73 gear inches. With a 9 tooth high cog (and same low of 28), it would be 19.5-89.2 gear inches, that's a winner. I don't know if you can put a 9 tooth on a standard freehub body used with the original 11-28. Assuming the seatpost is standard Dahon diameter, the seat tube should be same outside diameter as Dahon's other aluminum bikes (unless the stresses are higher?); I've done a front derailleur mount on Dahon's steel frame and it just barely worked, the aluminum frame is just slightly larger in diameter there, I think a mm, and they make an adaptor, but the fit there is critical in letting the derailleur go far enough in for the inner chainring.
Flashbacks of Cannondale mono forks.

Might make front hub selection and/or replacement a challenge.
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Old 01-27-24, 08:31 PM
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Originally Posted by CrimsonEclipse
Flashbacks of Cannondale mono forks.

Might make front hub selection and/or replacement a challenge.
Yeah I almost called it a Lefty, when in fact it's a Righty.

My first drooling on a folding bike was seeing the original Giant Halfway, which if I recall correctly, had single side forks front AND rear. I drooled over both the folding, and easy flat fixes. But I'm glad I didn't buy; It required a special rack (due to the single fork rear), was heavy, and impossible to mount a front derailleur (due to the non-cylindrical seat tube). But perhaps both front and rear hubs were special. That sounds expensive. My guess is it used standard hubs but with special axles, not too hard to tool up, just like bolts, but may have required stronger steel due to a lot of moment on the right dropout, and not just mostly shear (with a cassette; older freewheel hubs had more bending on axles, the reason for freehubs), and perhaps a flare or a big steel washer between the right locknut and dropout, to spread the load.

I don't ride motorcycles but am a fan of the design, and all my favorite motorbikes happen to have single sided rear forks, originally developed for fast wheel change in racing.

Last edited by Duragrouch; 01-27-24 at 08:36 PM.
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Old 01-27-24, 08:48 PM
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Found this while searching for price on Curl D9, this relates to the Curl i4, internal gear hub:

A potential downside to the Curl is the relatively modest 187 lbs (85 kg) maximum load capacity. That’s only 77% of the Brompton’s capacity, but it still suits many riders. And it’s a nicely made bike, as you’d expect from Dahon.
That load is well below other Dahons, usually 231 lbs max (and higher with Deltech). I am guessing that is because of the hub bearings of the IGH, versus a derailleur hub. This is one of the reasons I have cited for (my perceived) market failure of the Dahon Speed TR (touring), with IGH.
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Old 01-27-24, 09:01 PM
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Originally Posted by Duragrouch
Yeah I almost called it a Lefty, when in fact it's a Righty.

My first drooling on a folding bike was seeing the original Giant Halfway, which if I recall correctly, had single side forks front AND rear. I drooled over both the folding, and easy flat fixes. But I'm glad I didn't buy; It required a special rack (due to the single fork rear), was heavy, and impossible to mount a front derailleur (due to the non-cylindrical seat tube). But perhaps both front and rear hubs were special. That sounds expensive. My guess is it used standard hubs but with special axles, not too hard to tool up, just like bolts, but may have required stronger steel due to a lot of moment on the right dropout, and not just mostly shear (with a cassette; older freewheel hubs had more bending on axles, the reason for freehubs), and perhaps a flare or a big steel washer between the right locknut and dropout, to spread the load.

I don't ride motorcycles but am a fan of the design, and all my favorite motorbikes happen to have single sided rear forks, originally developed for fast wheel change in racing.
Mixed feelings.
The minimalist side likes the reduced complexity and better fold
The engineer side is concerned with the asymmetrical loads and extra material required to compensate for it.
The cheap bastard side is concerned with Even MORE hard to source/replace parts.

I like it, but I'll have to pass on this one.
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Old 01-27-24, 09:21 PM
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Originally Posted by CrimsonEclipse
Mixed feelings.
The minimalist side likes the reduced complexity and better fold
The engineer side is concerned with the asymmetrical loads and extra material required to compensate for it.
The cheap bastard side is concerned with Even MORE hard to source/replace parts.

I like it, but I'll have to pass on this one.
I hear ya, I'm a retired mechanical engineer. I'm also cheap, not willing to spend thousands on a bike but one around a thousand and equals my current setup, turn-key, is decent value, but I'm especially cost sensitive on parts cost for ongoing maintenance, a reason I like 8 speed cassette, cogs and chain are still full width so more durable, and parts are now dirt-cheap on amazon. (What's my name? )

The counterpoint is that Dahon are cheap b@stards, and sensitive about warranty costs (though they stiffed me on my cracked frame), and hubs and axles are "wear and tear" items, will probably last the warranty period of 1 year(?) (EDIT: 5 years on frame, 2 years on non-wear components), and would need to be addressed with the component maker. I'd like to get a close look at the monofork axle attachment and geometry. The fork I'm less concerned about, if forks start breaking due to fatigue failure, that's a CPSC recall, guaranteed, so I'm sure Dahon has done their homework in design, and hopefully, performed cyclic fatigue tests using both design load data, and actual load measurements from riding under worst loads and terrain, as shock loads can very greatly based on factors besides the fork, like tires, frame elasticity, rider position, etc. I would guess by this point, Dahon has tons of real-world data for that, but again, assuming they run fatigue tests.

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Old 01-28-24, 03:53 AM
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The latest Decathlon folding bike also has a mono fork also to reduce the folded width with the same problem of proprietary front hub (same for the Helix, yet another proprietary frnt hub due to a mono fork).

No, its not possible to put a cog smaller than 11t on a standard Shimano freewheel body.

The most standardized manner to go below 11T (10t or 9T) is to use a SRAM XD or XDR freewheel body, that's what I did on my two Birdy and what Helix did on the ultralight with the same type of Ethirtheen cassette I have (these not only have a 9t smallest cog excellent for small wheel bikes but are also lightweight, with a Tune or Hope rear hub, its a real weight saving vs. usual Shimano hub+cassette cassettes).

Moulton designed a proprietary hub with a Campagnolo derived freewheel body that accepts a 10t smallest cog (on proprietary cassettes).

Sunrace has a proprietary hub derived from the discountinued Shimano Capreo with several 9s, 10s and 11s cassettes (mounted by Riese & Müller on the Birdy 3 Touring) but all these components are difficult to find (and are heavier than the Ethirtheen + Tune or Hope).
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Old 01-28-24, 05:49 AM
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Originally Posted by Jipe
The latest Decathlon folding bike also has a mono fork also to reduce the folded width with the same problem of proprietary front hub (same for the Helix, yet another proprietary frnt hub due to a mono fork).

No, its not possible to put a cog smaller than 11t on a standard Shimano freewheel body.

The most standardized manner to go below 11T (10t or 9T) is to use a SRAM XD or XDR freewheel body, that's what I did on my two Birdy and what Helix did on the ultralight with the same type of Ethirtheen cassette I have (these not only have a 9t smallest cog excellent for small wheel bikes but are also lightweight, with a Tune or Hope rear hub, its a real weight saving vs. usual Shimano hub+cassette cassettes).

Moulton designed a proprietary hub with a Campagnolo derived freewheel body that accepts a 10t smallest cog (on proprietary cassettes).

Sunrace has a proprietary hub derived from the discountinued Shimano Capreo with several 9s, 10s and 11s cassettes (mounted by Riese & Müller on the Birdy 3 Touring) but all these components are difficult to find (and are heavier than the Ethirtheen + Tune or Hope).
Umm, good info. Might I ask, which of the freehubs above, that can mount a 9 tooth cog, do NOT require their own proprietary hub to mate to, but can be swapped out for whatever freehub comes standard on the Curl D9? (Which I'm guessing is some sort of Shimano freehub clone, but IIRC they come in several interface geometries, some attach with bolt from the right, some from the left...)

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Old 01-28-24, 09:54 AM
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Both the rear hubs of Hope and of Tune have the SRAM standardized XDR body and allow to change the body for the standard old Shimano and several others (campagnolo standard, crap Shimano Microspline...).
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