Brompton how light can it go

[TheDoctor]

Carbon brakes? Seriously?
I mean, I'd love one, but bits of that look as fragile as anything.
I still want one.

 

[T4tomo]

The solution to it being" a bit heavy to carry" is to ride it or wheel it.

 

[novetan]

As I was googling how to lighten a Brompton, this thread pop out. Though already past a few yrs, hope someone can advise.
I believed Brompton do have options, changing the rear triangle and fork to Ti and a saving of 700g but would add another USD $1000. But wonder why brompton no option for main frame. There are Ti main frame selling on line and just a wild guess that could be the main weight saver. Ti main fr weigh 1500g. Anyone knows whats the weight for steel? It don't come cheap though, costing ard USD$2000 for Ti main frame.

 

[Gunk]

Just as important is how light can you yourself become....as a 17stone Brompton user myself Ihave given up light bikes. Body weight would be much easier and cheaper to get off....Titanium oiptions would be more for strength than weight reduction in my case.. eg..as a heavier rider I find seat post stems can bend just a touch over time making them a tough fold.Steel ones are cheap to replace though at a fifth of the price of titaniuim)..

very good point, I’ve managed to lose 3 kg over lockdown, much cheaper than replacement titanium forks and seat post!

 

[berlinonaut]

As I was googling how to lighten a Brompton, this thread pop out. Though already past a few yrs, hope someone can advise.
I believed Brompton do have options, changing the rear triangle and fork to Ti and a saving of 700g but would add another USD $1000. But wonder why brompton no option for main frame. There are Ti main frame selling on line and just a wild guess that could be the main weight saver. Ti main fr weigh 1500g. Anyone knows whats the weight for steel?

The steel version weights around 2100g. So the weight saving by a ti main frame is there but way less than one would expect. And that saving comes at a very steep price, even that those actual ti frames are not hand brazed in London but made in China, unlicensed, untested for safety and quality and in unclear social and enviromental conditions. Apart from the fact that - judging from what users say - the chinese Brompton-clone ti main frames seem to have the stiffness of cooked spaghetti.
Which seems obvious when looking at the properties of titanium and steel - just using titanium building the more or less idential measurements of the steel version leads to that result - a proper titanium main frame would need some refinement. Google for the UFB (Ultimate Folding Bike) by Len Rubin - a titanium Brompton clone that was made years ago and estimated to sell at a very high price. The tubing looks "somewhat" different from that of the chinese frames - probably for a reason...

 

[simongt]

As a Brommy is designed only to be carried relatively short distances; further, then half fold and trundle on the mini wheels, is there really any point in this discussion apart from the aesthetic - ?

 

[Gunk]

As a Brommy is designed only to be carried relatively short distances; further, then half fold and trundle on the mini wheels, is there really any point in this discussion apart from the aesthetic - ?

quite agree

 

[berlinonaut]

As a Brommy is designed only to be carried relatively short distances; further, then half fold and trundle on the mini wheels, is there really any point in this discussion apart from the aesthetic - ?

Sure there is. A Brompton is also designed to be a "city bike" - look what people are using it for... Regarding the weight: I live on the forth floor of an old house and have to carry the bike down in the morning and up in the evening. That's slightly more than 100 stairs one way - at least twice each day. Similar situation (though less stairs) in my office. Similar situation in most railway stations and many, many other situations. So yes, weight does matter and less weight is very welcome as long as it is affordable and does not limit the practical usage of the bike (which in my case i.e. means: blades and dynamo lights are mandatory as is the necessary robustness for everyday usage).

 

[novetan]

The steel version weights around 2100g. So the weight saving by a ti main frame is there but way less than one would expect. And that saving comes at a very steep price, even that those actual ti frames are not hand brazed in London but made in China, unlicensed, untested for safety and quality and in unclear social and enviromental conditions. Apart from the fact that - judging from what users say - the chinese Brompton-clone ti main frames seem to have the stiffness of cooked spaghetti. Which seems obvious when looking at the properties of titanium and steel - just using titanium building the more or less idential measurements of the steel version leads to that result - a proper titanium main frame would need some refinement. Google for the UFB (Ultimate Folding Bike) by Len Rubin - a titanium Brompton clone that was made years ago and estimated to sell at a very high price. The tubing looks "somewhat" different from that of the chinese frames - probably for a reason...

Currently I’m riding a clone brompton which is 3Sixty. Honestly it is really not that bad at 1/3 the price. One would not able to tell the diff in a blind fold test ride. They are using Sturmey Archer hub and shifter. The rest are merely welding and assembly work, so its not rocket science. Quality wise may not be super if u don't take a closer peep. You get what you paid. Good enough to bring me ard.

I do have some engineering knowledge. To break a weld is really not that easy. The Ti frame is 1500g, costing ard USD $2000. To save 600g at an exhorbitant add cost of 2k for sure is not justify. Better off to swap the fork and triangle if one were to look into wt savings.

I agreed with many here in previous posts the bike is way too heavy. And for 40 yrs almost nothing change is actually not forward looking. Brompton is so sellable. If they were to engineer a Ti version, am sure they can create a niche market whilst maintaining the config.

 

[novetan]

As a Brommy is designed only to be carried relatively short distances; further, then half fold and trundle on the mini wheels, is there really any point in this discussion apart from the aesthetic - ?

I supposed different stroke for different folks. Some attune to more practical thinking, some prefer to splurge before they hit the grave. I got someone already answered my query. So will not drag the topic. Cheers

 

[berlinonaut]

Currently I’m riding a clone brompton which is 3Sixty. Honestly it is really not that bad at 1/3 the price. One would not able to tell the diff in a blind fold test ride.

Well, in my eyes that's a bad start. I would not buy from people stealing other people's intellectual property as shameless as the 360 people did. And there are way enough shortcuts on that interpretation of a Brompton and it is based on an early 90ies design that got frankensteined to the worse. Your buy makes your statement even stranger:

And for 40 yrs almost nothing change is actually not forward looking. Brompton is so sellable.

Well, you did not buy one but a cheap (in multiple ways) copy. So you already proved that the development ist not of value to you as you are neither willing to pay for it nor to even pay for the development that has already happened - you bought a pirated copy instead from people that did not invest a single penny in development.

Regarding your "40 years no development" statement I'd recommend looking again. No one would hoenstly say a Mk1 from 1980 would be even close to a today's Brompton - the current raw shape started with the MK2 in 1987, that's 33 years. A Mk2 and an actual Brompton have exactly two parts in common: The rear hinge and the plastic bit on the stem that holds the stem in folded state. Every other bit and part has changed, most of them more than once. If you want change go and buy a Dahon - they change their parts and models so frequently that they are not able to provide spare parts or at least reliable data about their current lineup...

 

[novetan]

...

 

[novetan]

Well, in my eyes that's a bad start. I would not buy from people stealing other people's intellectual property as shameless as the 360 people did. And there are way enough shortcuts on that interpretation of a Brompton and it is based on an early 90ies design that got frankensteined to the worse. Your buy makes your statement even stranger:

Well, you did not buy one but a cheap (in multiple ways) copy. So you already proved that the development ist not of value to you as you are neither willing to pay for it nor to even pay for the development that has already happened - you bought a pirated copy instead from people that did not invest a single penny in development.

Regarding your "40 years no development" statement I'd recommend looking again. No one would hoenstly say a Mk1 from 1980 would be even close to a today's Brompton - the current raw shape started with the MK2 in 1987, that's 33 years. A Mk2 and an actual Brompton have exactly two parts in common: The rear hinge and the plastic bit on the stem that holds the stem in folded state. Every other bit and part has changed, most of them more than once. If you want change go and buy a Dahon - they change their parts and models so frequently that they are not able to provide spare parts or at least reliable data about their current lineup...

Me buying a clone seems to hit a raw nerve of you. You are incorrect to state 360 is stealing Brom intellectual property. There are articles you can check it out their licence are over. So it is legitimate. There are already a few clones, Pike Elements and two others which is less popular.

I applaud Brom retain the basic config besides the minor tweaking which I‘m not blinded. I admit it’s the best fold. Why reinvent the wheel when its aren’t broke. That is one reason I bought the 360 albeit a clone. And it is uniquely chromed which Brom don't have. Besides its 1/3 the price and all I want is some fun riding. I can have the cake and eat it. SpaceX has ventured into materials that re-entry will not subject to falling tiles. Selle Anatomica took a step further over Brooks with their leather saddle in different thickness and lighter that don’t require 500 or 1000 miles to break in. That is innovation. Of course not everyone can attest to Selle and some has gone back to Brooks. On the same token, some would hv gone back to Brom after trying out the bike clone. To each his own.

You can brag all you want carrying the brom over 100 stairs twice a day. Not everyone is as musular as you. What am saying brom shld attempt to innovate the material portion, not to change config like Dahon or Tern. Some has called for carbon even. But personally I think that is a tough call when folding is involved.

Anyway, its not my business shld Brom wish to remain status quo for the next 100 yrs. I’m not suggesting them to explore rocket science material. Just kind of making it lighter where u already hv a bunch of people complaining- as far as I know reading fr various articles. Then some will argue u r suppose to ride or atmost push wheel a few feet away, as if they knew their situation. Anyway with brom remain less innovative will keep many hobboyists happy in building up a ti frame, me included potentially.

I got the answer fr you. TQ for that. The main frame wt diff comes up to 600g and that would allow me a cost evaluation. Now u may say it doesn't add up since I'm prepare to part with my cash. I can give you another tonne of reasons. So its unproductive for a protracted argument here as it was already a very old thread, besides I know my direction now.

 

[berlinonaut]

Me buying a clone seems to hit a raw nerve of you.

Judging from your latest post it seems rather to hit a nerve with you....

You are incorrect to state 360 is stealing Brom intellectual property. There are articles you can check it out their licence are over. So it is legitimate.

Did you read about the recent court case that Brompton won against Chedtech? https://www.cyclechat.net/threads/b...opyright-case-against-get2get-chedech.264679/ There's probably a reason why 360 do not dare to offer their bikes in Europe....

You can brag all you want carrying the brom over 100 stairs twice a day. Not everyone is as musular as you.

Ad-hominem-attacks to not make your argumentation any better.

 

[novetan]

IP laws are complicated and depends what areas you want protected. Design, folding, functional, etc etc. Not forgetting you have to apply worldwide coverage too. If they don’t cover a particular country, then that country have every right to copy. That is the law. I’m not here to encourage pilferage. Am sure Brom got good advise its not worth to cover China. Then which country 360 wish to sell is beyond our discussion here.

That doc you attached is just a general news. You and me do not know the details enough to make a judgement. Nothing is considered cast in stone as the defendant can appeal until everything is exhausted. Then that is the judgement.