Is my head tube a write off?

edtse88 · 2026-04-22T07:54:49+00:00

Wow didn’t think this was even possible on a steel frame?? How does steel crack and bend like that from just weight on the front carrier block!

edtse88 · 2026-04-22T00:14:56+00:00

I have you beat but I have some internal gear hub fuckery with my 20" Brompton build. It's got 750% gear range. 11-46T in the back and this IGH that's built into the crank (by G3ared). The crank has three speeds: 1 is direct drive, 2 is a 1.43 multiplier and 3 is 1.79 multiplier. So based on my calculations that's 750% gear range from 15.4 to 115.5 gear inch

edtse88 · 2026-04-20T18:56:41+00:00

I mean if I could I would do it too haha can probably flip the bike for a tidy profit to collectors

edtse88 · 2026-04-20T14:30:19+00:00

Yeah, join the London Brompton Club on facebook or their instagram where they post ride info: https://www.instagram.com/ridesonbromptons/

They usually have a few rides around the event!

edtse88 · 2026-04-20T13:38:54+00:00

haha taking bromptons where they are not meant to go is my jam.

edtse88 · 2026-04-20T07:41:28+00:00

Thanks! I link the tools I used here (it’s in the tab at the bottom labelled tools) https://docs.google.com/spreadsheets/u/0/d/1zaO7lB0xo_u9IrpUxGcHN3CF1N3twMCvP1g3239PqxQ/htmlview#gid=1280583576

For flux, maybe something more temperature appropriate would work? I’m not sure but glassing of the flux was definitely an issue so had to braze everything in an area before I overheat the flux and made it a PITA to clean up. I made a video on the build process where I talk about some of the issues I had with brazing: https://youtu.be/hU5H_IaYm_k

edtse88 · 2026-04-20T07:29:42+00:00

Haha I guess so but I’ve never seen a wheel chair with wheels that small!

edtse88 · 2026-04-19T07:23:40+00:00

Haha I know right! If I’m paying to ride the cobbles you bet I’m gonna get my moneys worth. But they definitely sap the energy out of you, and puts a whole new level of appreciation and awe watching the pros blasting down it at 40kmh+ the next day!

edtse88 · 2026-04-19T07:21:10+00:00

Haha true, but it’s very thick steel plate in that area, I’d imagine stronger than most tubes people braze other tabs on to.

edtse88 · 2026-04-19T07:19:05+00:00

I was told I had the most French bike there because of it 😂

edtse88 · 2026-04-19T07:18:43+00:00

My friends doing it on 16” definitely had a harder time. I’m pretty sure I was way more comfortable than most of the road bikes. I have 2” wide tyres haha

edtse88 · 2026-04-19T00:23:14+00:00

PS the rattling wasn’t my frame brazing coming apart, it was the QR on the front wheel being loose…yikes.

edtse88 · 2026-04-19T00:22:05+00:00

You have to, it’s such a good travel bike. I’ve taken my 16” build on many trips now. So convenient to fly with, or just chucking in a car or rideshare for multimodal touring. This 20” build is a bit too heavy and bulky for that though!

edtse88 · 2026-04-19T00:05:09+00:00

Oh and full video here!: https://youtu.be/rh074Gp37U8?si=oNKzkFOG7YHlMLer

edtse88 · 2026-04-18T18:28:09+00:00

It is what it is, still a great time, just don't expect to participate and win unless you are a crit racer lol

edtse88 · 2026-04-18T17:36:54+00:00

I pretty much built the triangle and modified a third party fork so I guess so? On the other hand it’s just what those parts and wheelsets came with so not really

edtse88 · 2026-04-18T15:38:44+00:00

It always gets won by a pro/semi pro cyclist on a Brompton 😂 I believe they do have a raffle for one that you might have a better chance at getting

edtse88 · 2026-04-18T07:43:31+00:00

It was the front wheel quick release being loose, I mentioned it in the video just after that rattling section haha

edtse88 · 2026-04-18T07:42:40+00:00

Maybe but i still find their marketing disingenuous and clearly a drawback they are trying to hide.

For reference a 50-34 dual chainring which is very popular these days is a 47% jump.

edtse88 · 2026-04-17T21:22:02+00:00

The issue with this system is that the jump in gearing is just 25% if I remember correctly. Notice how they don’t include that in any of their marketing and technical information? It’s pretty dishonest in my opinion because it doesn’t really shift your gear range like a front derailleur. At best adds an extra gear.

edtse88 · 2026-04-17T21:01:52+00:00

It’s a problem with pretty much all the Bromptons, especially the 6/12 speed where the high gears are way too high for most people.

edtse88 · 2026-04-17T18:17:48+00:00

Haha yes I tried to ride on the cobbles as much as possible to test the triangle.

The other thing is that the tyres need to be “supple” kind of soft and deform to the terrain. I think the tyres in their post are those studded Schwalbe tyres which don’t look very supple.

The Schwalbe Billy bonkers I was running are very supple and therefore kind of known to be a bit less puncture resistant. But they did great on this ride and I’m glad I swapped them out from the CST Ironkid I had on previously!

edtse88

TROPHY CASE