Is it not the best time to build a Brompton Ti clone?
#1
Junior Member
Thread Starter
Is it not the best time to build a Brompton Ti clone?
Just thinking out loud, given that Brompton (and other folders) have risen in price due to a shortage of supply, I'm a bit surprised by folks spending several thousands just to get the vanilla Brompton, when they could spend perhaps a bit more for a much lighter machine. Any word on the best ebay sellers for Brompton titanium clones?
#2
Senior Member
Join Date: Aug 2011
Location: Paris, France
Posts: 2,497
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 573 Post(s)
Liked 118 Times
in
99 Posts
It doesn't take "several thousands" to shed a vanilla Brompton the ~1kg/2lbs saved by buying the Ti version: Not sure, but just getting lighter rims* (and a ti seatpost) could do the trick for much less.
https://www.atob.org.uk/folding-bike...ight-brompton/
* or tires, at the expense of increasing risk of punctures
https://www.atob.org.uk/folding-bike...ight-brompton/
* or tires, at the expense of increasing risk of punctures
Last edited by Winfried; 08-16-20 at 03:58 AM.
#3
Senior Member
Join Date: Feb 2017
Posts: 1,544
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 800 Post(s)
Likes: 0
Liked 247 Times
in
211 Posts
I do not agree with this statement.
For the Ti seatpost, the original one 520mm long weight about 400g. The Pentaclip weight a little more than 100g.
A Ti seatpost with integrated saddle mount weight about 300g.
In total, the replacement saves only 200g.
For the rims, and spokes, unless you reduce a lot the amount of spokes, the weight reduction will be very small with the same hubs.
So, starting from a superlight Brompton or a CHPT3 with lightweight front hub and keeping the internal gear hub to keep the same 6 speed transmission won't save a lot. Moving to a 1s or 2s transmission save weight but reduce the capabilities of the bike.
I say start from a superlight or CHPT3 because nothing can replace the 800g savings of the Ti fork and rear triangle, all other mods are also possible with these Ti parts, meaning that the same mods applied to a bike with Ti fork and rear triangle will always be lighter than the same bike with same components and steel fork and rear triangle.
The other big weight savings are replacing the saddle by a full carbon saddle, replacing the pedals by Ti axle lightweight left removable pedals, replacing the bottom bracket and crankset (the saving depends of the amount of money you have, the biggest saving will be with something like the THM Clavicula SE) and moving to 11s chain/cogs, brake levers and brake caliper.
At the end of the day, none of the original components will remain and the total price of the bike is multiplied by a factor 2 or 3 !
Next step could be a carbon or Ti stem and last one a Ti main frame.
Changing tires for lightweight types like Schwalbe One will also provide a big saving but it also reduce the puncture resistance and increase the risk of puncture a lot, so like for suppressing the internal gear hub, the capabilities of the bike are changed.
For the Ti seatpost, the original one 520mm long weight about 400g. The Pentaclip weight a little more than 100g.
A Ti seatpost with integrated saddle mount weight about 300g.
In total, the replacement saves only 200g.
For the rims, and spokes, unless you reduce a lot the amount of spokes, the weight reduction will be very small with the same hubs.
So, starting from a superlight Brompton or a CHPT3 with lightweight front hub and keeping the internal gear hub to keep the same 6 speed transmission won't save a lot. Moving to a 1s or 2s transmission save weight but reduce the capabilities of the bike.
I say start from a superlight or CHPT3 because nothing can replace the 800g savings of the Ti fork and rear triangle, all other mods are also possible with these Ti parts, meaning that the same mods applied to a bike with Ti fork and rear triangle will always be lighter than the same bike with same components and steel fork and rear triangle.
The other big weight savings are replacing the saddle by a full carbon saddle, replacing the pedals by Ti axle lightweight left removable pedals, replacing the bottom bracket and crankset (the saving depends of the amount of money you have, the biggest saving will be with something like the THM Clavicula SE) and moving to 11s chain/cogs, brake levers and brake caliper.
At the end of the day, none of the original components will remain and the total price of the bike is multiplied by a factor 2 or 3 !
Next step could be a carbon or Ti stem and last one a Ti main frame.
Changing tires for lightweight types like Schwalbe One will also provide a big saving but it also reduce the puncture resistance and increase the risk of puncture a lot, so like for suppressing the internal gear hub, the capabilities of the bike are changed.
Likes For Jipe:
#4
Banned
There is a Ti Clone frame, coming out of China.. I see them touted on the Brompton hacks.. facebook group
No personal interest in them , you're on your own with the eBay hunt...
...
No personal interest in them , you're on your own with the eBay hunt...
...
Last edited by fietsbob; 08-16-20 at 11:10 AM.
#5
Senior Member
Join Date: Sep 2005
Location: Michigan
Posts: 3,706
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 840 Post(s)
Liked 336 Times
in
251 Posts
I got Ti handlebars for Brompton, to the best of my knowledge manufactured by the main manufacturer of Ti Brompton part renditions in China, Comeplay Titanium Bike, The left side of these handlebars rises, see here, by about 0.5" higher than the right.
If you want to set on that route, good luck, but I am afraid that having luck might not be enough. Ruminating, certainly money would help, to make several purchases hoping that one will be OK and work. Maybe metal working skills would help too, to fix the flawed items. Given the work material, what about a Ti welding shop??
If you want to set on that route, good luck, but I am afraid that having luck might not be enough. Ruminating, certainly money would help, to make several purchases hoping that one will be OK and work. Maybe metal working skills would help too, to fix the flawed items. Given the work material, what about a Ti welding shop??
#6
Junior Member
Thread Starter
Wow that's bad quality in those handlebars, yes it is a risk.
The main point I was trying to make is that right now, brompton prices are up by a lot. So, instead of paying $5000 for a chapter 3 like I've seen people do recently, why not spend that money on a full titanium build?
But yeah quality worries...
The main point I was trying to make is that right now, brompton prices are up by a lot. So, instead of paying $5000 for a chapter 3 like I've seen people do recently, why not spend that money on a full titanium build?
But yeah quality worries...
#7
Senior Member
Join Date: Sep 2005
Location: Michigan
Posts: 3,706
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 840 Post(s)
Liked 336 Times
in
251 Posts
In my opinion it is hard to beat the value that the established brands, such as Brompton, Bike Friday, Birdy or Dahon, provide. Folders are in many ways more tricky than regular bikes and you generally get ironing out of all kinds of problems that can occur. Yes, you can improve upon them, see e.g. Jipe 's post, but at least you have a fine working bike that you can use in the meantime. Which bike to start from depends on personal circumstances including how you want to use the bike and the funds you can delegate.
#8
Senior Member
Join Date: Feb 2017
Posts: 1,544
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 800 Post(s)
Likes: 0
Liked 247 Times
in
211 Posts
Titanium alloy is another material than steel alloy with different mechanical properties.
Normally, when changing the material (even changing the type of alloy), the frame must be redimensioned to take this difference of mechanical properties into account.
Which I am afraid wasn't done for those Chinese Ti Brompton frame clones.
Normally, when changing the material (even changing the type of alloy), the frame must be redimensioned to take this difference of mechanical properties into account.
Which I am afraid wasn't done for those Chinese Ti Brompton frame clones.
#9
Schwinnasaur
Titanium alloy is another material than steel alloy with different mechanical properties.
Normally, when changing the material (even changing the type of alloy), the frame must be redimensioned to take this difference of mechanical properties into account.
Which I am afraid wasn't done for those Chinese Ti Brompton frame clones.
Normally, when changing the material (even changing the type of alloy), the frame must be redimensioned to take this difference of mechanical properties into account.
Which I am afraid wasn't done for those Chinese Ti Brompton frame clones.
Last edited by Schwinnsta; 08-17-20 at 04:28 PM. Reason: Changed to the text
#10
Stardust
I got Ti handlebars for Brompton, to the best of my knowledge manufactured by the main manufacturer of Ti Brompton part renditions in China, Comeplay Titanium Bike, The left side of these handlebars rises, see here, by about 0.5" higher than the right.
If you want to set on that route, good luck, but I am afraid that having luck might not be enough. Ruminating, certainly money would help, to make several purchases hoping that one will be OK and work. Maybe metal working skills would help too, to fix the flawed items. Given the work material, what about a Ti welding shop??
If you want to set on that route, good luck, but I am afraid that having luck might not be enough. Ruminating, certainly money would help, to make several purchases hoping that one will be OK and work. Maybe metal working skills would help too, to fix the flawed items. Given the work material, what about a Ti welding shop??
wow, thats a bummer.
i can imagine how big flaws can be in main parts like frame or a seatpost!
#11
Senior Member
Join Date: Feb 2017
Posts: 1,544
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 800 Post(s)
Likes: 0
Liked 247 Times
in
211 Posts
But you can't tell that. First they are roughly the same strength steel and titanium. Second, they may use the same outer dimension and not the same inner dimension. Buying Chinese Ti is though a pig in a poke. I guess on eBay you could go by Sellers feedback buy that is not that reliable.
But I doubt they made a real study of their frame design to compute what type/dimension of tubes are needed.
Also, nobody knows the quality of the welding which is crucial for a titanium frame.
I also had several bad experiences with Brompton third party components (including the very expensive brands) giving the impression that the designer/manufacturer actually never tested their components.
#13
Senior Member
Join Date: Feb 2017
Posts: 1,544
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 800 Post(s)
Likes: 0
Liked 247 Times
in
211 Posts
But the real question is: is a Brompton with a Ti clone frame with unknown mechanical characteristics better than a Brompton with the same components and an original Brompton superlight steel+Ti frame ?
Besides the tube dimensioning and welding issues, there could also be issues with the hinge, the rear triangle axle, seatpost mounting...
Besides the tube dimensioning and welding issues, there could also be issues with the hinge, the rear triangle axle, seatpost mounting...
#14
Senior Member
Join Date: Sep 2005
Location: Michigan
Posts: 3,706
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 840 Post(s)
Liked 336 Times
in
251 Posts
Parts manufacturing provides plenty of room for error, especially when they grow in complexity in the form or functionality. Even with that room you can theoretically get things done right if you have a high class people engaged, decent equipment and test a lot. The question is whether you have that. Are there market pressures for you to have that? My impression is that Glasgow Kinetics is on the right track, as well as Eerder Metaal or Juliane Neuss. On the Ti side, maybe Vostok Cycle Works is professional. However, the latter do not try to make copies of Brompton parts but design the form and size on their own. I am not sure whether Vostok is still operational, which also illustrates the problem that once you dive into something custom you may be left in the cold if you need a replacement part down the road.
Otherwise, shiny photos of a custom bike demonstrate nothing as far as practical utility thereof is concerned. When I put some aftermarket parts on the bike, they worked fine for the first half an hour of riding. Then things started to slip and after an hour I would have to stop on every block to reset the bike so that I could make it to the next block. A couple of times, I took a bike with an aftermarket replacement part, that was not fully tested, on a trip, and the riding there went completely down the drain. I wised up since and now presume the aftermarket part not to work until it I prove it or make it work. Come to think, on my Brompton I have very few aftermarket parts made specifically for Brompton, all simple and all modified at some level.
Otherwise, shiny photos of a custom bike demonstrate nothing as far as practical utility thereof is concerned. When I put some aftermarket parts on the bike, they worked fine for the first half an hour of riding. Then things started to slip and after an hour I would have to stop on every block to reset the bike so that I could make it to the next block. A couple of times, I took a bike with an aftermarket replacement part, that was not fully tested, on a trip, and the riding there went completely down the drain. I wised up since and now presume the aftermarket part not to work until it I prove it or make it work. Come to think, on my Brompton I have very few aftermarket parts made specifically for Brompton, all simple and all modified at some level.
Likes For 2_i:
#15
Senior Member
Join Date: Aug 2011
Location: Paris, France
Posts: 2,497
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 573 Post(s)
Liked 118 Times
in
99 Posts
Incidently, has someone been brave enough to order a 135mm rear triangle from TWTOPSE in China?
https://www.aliexpress.com/item/33024325243.html
https://www.aliexpress.com/item/33024325243.html
#16
Senior Member
Join Date: Sep 2005
Location: Michigan
Posts: 3,706
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 840 Post(s)
Liked 336 Times
in
251 Posts
I.e., when you consider placing an order, you should look right away what would happen if things went wrong. Money-back guarantee may stand for empty words when you need to send back a bulky item at your cost to another side of the world. Looking at left right symmetry for handlebars is easy but looking for other defects, as already mentioned, might not be as straightforward.
#17
Senior Member
Join Date: Aug 2011
Location: Paris, France
Posts: 2,497
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 573 Post(s)
Liked 118 Times
in
99 Posts
Too bad no one makes an affordable 135mm triangle in steel in the US/Europe. I don't take care about the weight, but I do care about sticking a Shimano gear hub in there :-)
#18
Stardust
Incidently, has someone been brave enough to order a 135mm rear triangle from TWTOPSE in China?
https://www.aliexpress.com/item/33024325243.html
https://www.aliexpress.com/item/33024325243.html
i probably take the bet with vostok in tailin, estonia.
my bike tour would be russia, moscow, st petersburg, helsink, and get in person the rear triangle and all gargets with vostok in person.
#19
Senior Member
Join Date: Sep 2005
Location: Michigan
Posts: 3,706
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 840 Post(s)
Liked 336 Times
in
251 Posts
Are you planning to do it all exclusively by bike? These are large distances with sparse population. On the other hand, with a Brompton it might not be that hard to hitchhike and there must be plenty of long-distance truck traffic there.
#20
Stardust
i do conect dots and explore cool places by bike.
i plan to take brompton and just do urban bike with it in interesting places in tonws.
ideal route
hang around in moscow(ktrmlin and red square) - train to saint petersburg(venice of the north), hang around there, train to helsink(archtects dreamland) ferry boat to taillin(shaddy capital of sadness) ...
of course only after pandemic...
Last edited by BromptonINrio; 08-19-20 at 01:33 PM. Reason: do
#21
Senior Member
Join Date: Sep 2005
Location: Michigan
Posts: 3,706
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 840 Post(s)
Liked 336 Times
in
251 Posts
Parking in the street in Russia or Baltics is pretty much out of question, but then Rio must prepare you well in strategizing
Likes For 2_i:
#22
Stardust
Likes For BromptonINrio:
#23
Banned
USA trashed it's passenger rail system, Europe, East and West, Rebuilt it ,,, Brompton was made for rail commuting.
Likes For Jipe:
#25
Stardust