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-   -   Yet another titanium Brompton build (https://www.bikeforums.net/folding-bikes/1170296-yet-another-titanium-brompton-build.html)

Raxel 04-10-19 12:53 PM

Yet another titanium Brompton build
 
I have suddenly realized that I have amassed enough Brompton parts to build a whole bike... so I did.
Only the main frame is titanium, and rest of the bike are steel.

The tires were much heavier than expected (sample variance) so I end up missing the sub-7kg target weight though.
(I am still waiting for titanium bolts for brakes which may shave ~40gr)


https://cimg6.ibsrv.net/gimg/bikefor...c26b8f6819.jpg
https://cimg1.ibsrv.net/gimg/bikefor...a753cdf5b8.jpg
https://cimg9.ibsrv.net/gimg/bikefor...88f030353d.jpg

univega.duder 04-10-19 03:13 PM

Wow Raxel- this one looks great! Is that the 3sixty frame? Did you have any issues putting it together?

jadocs 04-10-19 08:27 PM

That’s beautiful. I want it.

blakcloud 04-11-19 03:47 AM

Nicely done!

Mcarto 04-12-19 01:04 PM

How much cost titanium frame? I can not find any open auction on ebay.

rhenning 04-12-19 03:46 PM

Lots of them on e-bay you just have to look. Some are buy it now. Most a $1200 to $3000 range. Roger

chagzuki 04-12-19 04:43 PM

Does the ti frame use a metal seat post shim/sleeve or a plastic one like the Brompton original?

Mcarto 04-13-19 05:18 AM


Originally Posted by rhenning (Post 20882204)
Lots of them on e-bay you just have to look. Some are buy it now. Most a $1200 to $3000 range. Roger

Yep but not on the 3sixty frame, I also found a lot of frames from various manufacturers on Alibaba.

Raxel 04-13-19 09:32 AM


Originally Posted by Mcarto (Post 20881938)
How much cost titanium frame? I can not find any open auction on ebay.

Main frame usually costs around $900~1K.


Originally Posted by chagzuki (Post 20882268)
Does the ti frame use a metal seat post shim/sleeve or a plastic one like the Brompton original?

Most titanium third party frames uses CORK sleeve which seems to grab the seatpost much better than stock plastic ones.

chagzuki 04-13-19 11:38 AM


Originally Posted by Raxel (Post 20882970)
Most titanium third party frames uses CORK sleeve which seems to grab the seatpost much better than stock plastic ones.

Interesting. I wonder how long it lasts. Does it need to be glued in place?

dahoneezz 04-13-19 08:47 PM

How is the rear hinge part done? Do you use Brompton parts for that? Or the titanium rear hinge comes with its own bushing and bolts. Also I think for the Brompton, you need some funky reaming tool to complete the job.

kidshibuya 04-13-19 11:56 PM

Usually I see bromptons as bikes for old ladys but this one looks cool, good job.

Raxel 04-16-19 11:20 PM


Originally Posted by dahoneezz (Post 20883623)
How is the rear hinge part done? Do you use Brompton parts for that? Or the titanium rear hinge comes with its own bushing and bolts. Also I think for the Brompton, you need some funky reaming tool to complete the job.

Titanium main frame comes with hinge bushing and seatpost sleeve pre-installed, and they are already reamed. One needs the hinge and hinge bolts though (There are lightweight aftermarket ones)

dahoneezz 04-17-19 06:01 AM

Thank you for the reply.

mlau 04-17-19 09:57 AM


Originally Posted by kidshibuya (Post 20883740)
Usually I see bromptons as bikes for old ladys but this one looks cool, good job.

Hey! I resemble that. lol.

Seahxkg 06-15-19 09:47 PM

Hi Raxel. Where did you purchase the expander cone for the quill stem? It does not come with the quill stem and I only seem to be able to find the bolt online.

fietsbob 06-17-19 02:30 PM

UFB may be only one..
 
https://scontent-sea1-1.xx.fbcdn.net...45&oe=5D90425F

fietsbob 06-17-19 02:34 PM

https://scontent-sea1-1.xx.fbcdn.net...70&oe=5D7B71B6

BromptonINrio 06-17-19 03:02 PM


Originally Posted by fietsbob (Post 20983367)

is this a flamingo brompton knockoff?

fietsbob 06-17-19 03:38 PM

Flamingos were Asia aluminum, this is cusrom Titanium .. un cheap .


Leonard Rubin's Own Bike see: facebook.com/UltimateFolder..

he posted pictures of the electronic shifting ..

BromptonINrio 06-17-19 07:46 PM


Originally Posted by fietsbob (Post 20983457)
Flamingos were Asia aluminum, this is cusrom Titanium .. un cheap .


Leonard Rubin's Own Bike see: facebook.com/UltimateFolder..

he posted pictures of the electronic shifting ..

oh, sorry, i didnt knew his work.
the toptube seems massive, or its just my eyes?
titanium seems more flexy that steel and alluminium, so make more sense they need to make thicker tubes...right?.
the tubbing is my main question against razels titanium brompton...does it flex more?

fietsbob 06-17-19 11:07 PM

I expect he specified it for added stiffness, since the alternative in TI

with a same as steel outside diameter would requite a much thicker tube wall..

95 pound asians may be fine with a noodly frame as long as they weigh less..

Raxel 06-18-19 01:42 AM


Originally Posted by fietsbob (Post 20983982)
I expect he specified it for added stiffness, since the alternative in TI
with a same as steel outside diameter would requite a much thicker tube wall..
95 pound asians may be fine with a noodly frame as long as they weigh less..

a) Brompton (as well as the UFB) has rear suspension, which will give WAY more than any possible frame flex anyway.
b) Fork and rear frame has much thinner tubing than the main frame, and they flex way more than main frame.
c) Long seatposts (especially carbon or titanium ones) flex a lot too.
d) Many people that weigh ~200lbs are riding their titanium brompton (clones) now and say they feel just the same as the original steel ones.

Onaut 02-19-20 02:59 PM

Raxel you installed the forged crankset (3sixty and other brands) from Aliexpress, right? Is it the square taper model or the GXP with axle and are you happy with it? I want to replace my Miche crankset, as it's ugly and scratches the rear triangle in folded position. I can't post links yet...

leinadhok 05-19-20 06:09 PM


Originally Posted by Raxel (Post 20878675)
...
(I am still waiting for titanium bolts for brakes which may shave ~40gr)

...

Hi Raxel,

When swapping the brake caliper bolts to titanium, is it advisable to apply anti seize or medium thread lock? Also, do I follow the default torque values set by Brompton in the user manual?


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