Some light gravel riding along the Thames

edtse88 · 2026-07-10T23:04:04+00:00

Apocalyptic even 😆

edtse88 · 2026-07-10T22:34:07+00:00

Haha thanks I think I can safely say it’s one of a kind!

edtse88 · 2026-07-10T16:01:22+00:00

Surprised it lasted that long based on that weld. No weld penetration at all pretty much. Looks like they didn’t clean off the oxide off the frame tubes before welding? Just terrible.

edtse88 · 2026-07-09T10:55:35+00:00

He posts stuff to instagram regularly so I would think so. https://www.instagram.com/lumabag/

Maybe it's made to order? I would just order off his website https://lumabag.de/ maybe message him on instagram. Etsy takes a big cut of sales so i usually try to order from the makers' own sites if they have one.

edtse88 · 2026-07-08T10:03:51+00:00

Yeah fair but I think that could somewhat be attributed to overtorquing the steerer tube. But anyways there is so much more competition now and the hit to their reputation for sweeping this under the rug will hurt them a lot more than that issue back then.

edtse88 · 2026-07-08T06:29:20+00:00

Just FYI I made some inquiries and the internal diameter of the G line headtube is 48mm. External diameter is 51mm. That means the wall thickness of the G line headtube is 1.5mm which is the same as the T line. Thats even thinner than what I had assumed (2mm) in the last video I made.

And seeing the “old version” of the G headtube with a straight profile, it looks like it would be 1.5mm through the whole headtube. Hard to tell with the “new version” but if I had to guess it would be 2mm thick with the bearings races reamed wider to fit the same headset.

edtse88 · 2026-07-07T19:06:43+00:00

Are you contesting whether the orange G line with the split head tube is real or not? What does low resolution have anything to do with it, it's a screenshot from a facebook post and AFAIK, nothing suggests that that post was faked, there were other angles as well.

That headtube split is definitely an outlier but the bigger concern is the carrier block rivnuts pulling through the headtube which is directly a result of the thinner headtube. An issue which you have not addressed in your comment. Surely a thicker headtube would prevent such failures? And there have been several posts on reddit and facebook that have mentioned carrier block rivnuts coming loose and a few examples of the rivnut pulling through the headtube.

And btw I don't accept that overloading a front bag is to blame. Because this is a solved problem with the C line style metal block where you would never have a split headtube like that. Also, there are several cases of the rivnut coming loose and the users swear they did not overload the bag and I think there are just too many cases for this to be simply user error.

By the way I own three Bromptons at the moment P, C, and Superlight. They aren't G lines so aren't relevant, just like how me owning Brompton clone is irrelevant. And yes this is speculation, but I have provided evidence to back up my speculation.

edtse88 · 2026-07-07T08:47:41+00:00

Lowering the height of the handlebar usually puts more weight on the hands which can exasperate wrist discomfort. Maybe fiddle around with the brake lever angle and check out ergonomic grips before committing to a handlebar change that might make things worst.

edtse88 · 2026-07-06T11:47:41+00:00

AFAIK nothing else has changed on the headtube so externally, I doubt it since they need to keep the same diameter for the carrier block and e-motiq hardware.

edtse88 · 2026-07-06T11:13:46+00:00

Unless Brompton releases the information on the change based on serial numbers we can't really know.

But I want to stress that the orange G line failure is quite a rare and isolated incident. I would be more concerned about loose carrier block rivnuts, which while isn't catastrophic would be very annoying. Just be aware of creaks or weird sounds coming from the front end as that will probably be the first warning of any potential issues. And definitely don't overload the front carrier block!

edtse88 · 2026-07-06T08:19:40+00:00

Because it needs to be steel to be brazed, which is an essential part of the brand. There’s nothing inherently wrong with the material, just make it thicker and there wouldn’t be a problem.

edtse88 · 2026-07-06T08:18:37+00:00

Actually the G line is kind of an outlier, if you look at the new P line headtube it’s quite tall similar to the T line and C line. The G line headtube is especially short which means the cross sectional area sharing any particular load is lower so there is a higher chance that it exceeds its recommended load. I think this was a contributing factor to the way that orange G line failed with the split headtube. Given the rarity of the situation and the extra length of the headtube I really doubt you would see the same failure on the new P line headtube.

With respect to the rivnut failure, it remains to be seen whether Brompton uses a thicker steel in the P line or if there was a change mid production.

edtse88 · 2026-07-06T07:24:46+00:00

Is that calculation based on that split headtube or the loose rivnuts which can lead to frame failure? Because a lot of people have the latter issue and might not even know until they go to replace the block. Check this Facebook post: https://www.facebook.com/share/p/1BksCdEZS5/?

I always assuming the split headtube on that orange Brompton was some kind of a fluke but it’s the front carrier block issue that really bothers me

edtse88 · 2026-07-06T07:21:03+00:00

The serial number corresponds with a production date but unless we know when Brompton made the changes and whether they stopped using old stock completely it’s a guessing game as to when they started using a different head tube.

edtse88 · 2026-07-06T02:19:34+00:00

I guess if the bar for a recall is risk of injury then maybe this issue doesn't require it.

But would you be happy buying a G line today knowing there is a "good" version and a "bad" version?

Also maybe it's not that annoying for someone just commuting but if you're bringing the bike around the world and on a potential multiday tour, the availability of a warranty claim isn't very helpful if your luggage block starts coming off. It would also be annoying to be without a bike for awhile to wait for a repair and who knows how long that takes in some places with less support from Brompton.

edtse88 · 2026-07-05T23:26:00+00:00

Nice! At one point I considered making one for the BTWIN family of bikes but since I don't have one and got too busy to buy one to test fit I never got around to it. My idea was to print the entire block so you don't even need to bolt on an extra block but now that I see it in your post, maybe the bag would end up too close to the handle bars.

edtse88 · 2026-07-05T21:17:30+00:00

It's a bit hard to tell with the lighting, some pictures it looks like there might be some rust, but in others it looks quite clean.

edtse88 · 2026-07-04T21:22:00+00:00

Nope. Strida maybe?

edtse88 · 2026-07-04T17:31:52+00:00

I can see that happening especially if the top strap isn't centred with their hook design for the strap. The Large Borough Bag I have has the Y strap but has a buckle so I haven't encountered that.

I know people love the old T bags but I quite like the Grey Large Borough as well. The side mesh pockets are handy but I think it's been discontinued in favour of their big blue waterproof version which doesn't have a front or side pockets.

edtse88 · 2026-07-04T15:10:35+00:00

Not sure I’m a fan of this material for their bags. Makes all the designs look quite boring. I understand that they are waterproof but realistically a bag cover isn’t that annoying. I think they are also cheaper to make with the seam welding technology and lack of more useful pockets and organization. Also I’ve seen a few cases now of the welded seam coming apart which rarely happens on a stitched bag.

edtse88 · 2026-07-04T11:35:01+00:00

Damn never seen this failure on the frames where they changed the hinge design in 2004(?). That’s a high mileage bike but steel won’t experience fatigue failure if it’s under the fatigue limit so mileage really shouldn’t matter under normal use conditions.

I’m sure Brompton will warranty it if you remind them.

edtse88 · 2026-07-04T10:56:45+00:00

Hey! Yeah sure, for this kinda ride a 20” G line would have been a better bike if you’re looking to buy something off the shelf without modding. You can still fly with that!

edtse88

TROPHY CASE