Brompton T Line w/ factory titanium mainframe
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Brompton T Line w/ factory titanium mainframe
Jipe broke this news buried on another thread.
Light. Pricey.
Is that a Hummingbird CF fork? Speaking of which, the single speed Brompton T is both heavier and more expensive than a British-built single speed Hummingbird. The 4-speed T is perhaps 250g lighter but has quite a bit narrower gear range than the 4-speed Hummingbird - and again the T is more expensive. Obviously the Brompton folds to smaller volume than the Hummingbird (but larger than a Dahon Curl
).
Light. Pricey.
Is that a Hummingbird CF fork? Speaking of which, the single speed Brompton T is both heavier and more expensive than a British-built single speed Hummingbird. The 4-speed T is perhaps 250g lighter but has quite a bit narrower gear range than the 4-speed Hummingbird - and again the T is more expensive. Obviously the Brompton folds to smaller volume than the Hummingbird (but larger than a Dahon Curl

Last edited by tcs; 01-19-22 at 07:57 AM.
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#3
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Pretty cool! Not cool enough to get that kinda money from me - and I don't ride carbon forks - but nice effort.
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Beautiful light bike.
Now the only difference with other Brompton is the lower weight (and titanium frame for those for who this is a selling argument).
It doesn't improve anything on the Brompton: same tire maximum width, no wider tire and as consequence probably same lack of comfort, same limited transmission (4s 163%), same caliper rim brakes (that limit tire width too).
And the normal high price for a titanium frame, relatively high end components bike.
I think that its a lot of effort to only sell small quantities, for most Brompton customer or potential customers, this bike doesn't change anything.
Now the only difference with other Brompton is the lower weight (and titanium frame for those for who this is a selling argument).
It doesn't improve anything on the Brompton: same tire maximum width, no wider tire and as consequence probably same lack of comfort, same limited transmission (4s 163%), same caliper rim brakes (that limit tire width too).
And the normal high price for a titanium frame, relatively high end components bike.
I think that its a lot of effort to only sell small quantities, for most Brompton customer or potential customers, this bike doesn't change anything.
#5
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Yep, it's a halo product. The numbers are in ebikes, which I expect an update on soon. They sent me a survey recently with several rear-hub-motor options to look at.
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That's really expensive!!! I thought @ £2K they were overpriced now £4K??? for that kind on money, I d rather get a cheaper 2nd hand brompton, refurb it and get a carbon gravel bike with the spare cash...
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Last edited by dezzie; 01-19-22 at 03:36 AM.
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Meh. Once again, except for the fold, the Bike Friday pakiT beats it on weight, price, and gears.
#11
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#12
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If you commute and thus need a compact bike that's easy to fold/unfold, there's no contest.
Besides, the Brompton is well designed for what most people use it for: Riding a few kms/miles to/from the station.
Besides, the Brompton is well designed for what most people use it for: Riding a few kms/miles to/from the station.
#13
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It doesn't improve anything on the Brompton: same tire maximum width, no wider tire and as consequence probably same lack of comfort, same limited transmission (4s 163%), same caliper rim brakes (that limit tire width too).
And the normal high price for a titanium frame, relatively high end components bike.
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Indeed, caliper brakes won't work with 50mm tire and disc will add weight. The solution is to use V-brake lightweight, powerful and accept wide tires.
But anyway, this is not possible as retrofit.
Solving the transmission limitation is possible but tricky, the only solution is to do what I did on my superlight Brompton: enlarge he titanium frame to 135 or 130mm and then mount a real derailleur but it requires also a new wheel and installing a new chain tensionner maybe the one of the Birdy III (on my Brompton I have a Rohloff which is heavier than a high end road derailleur).
But anyway, this is not possible as retrofit.
Solving the transmission limitation is possible but tricky, the only solution is to do what I did on my superlight Brompton: enlarge he titanium frame to 135 or 130mm and then mount a real derailleur but it requires also a new wheel and installing a new chain tensionner maybe the one of the Birdy III (on my Brompton I have a Rohloff which is heavier than a high end road derailleur).
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Did anyone get a email saying that they were chosen in the ballot to purchase a T line. I got one today and tried to log on but it wouldn't let me. I didn't have real intention of purchasing one as I have a 2 speed superlight but I wanted to check it out. I live in the USA and every time I tried to login it said that I don't have access to this page. Has anyone else had this experience? Personally I'd rather spend half the money and buy a Pakit at the same weight. I'm looking for a folding bike with 20 in wheels that will hold 2 inch tires. A coworker just bought a Zizzo Forte and I'm sure he's not going to ride it. I believe that bike will be mine in a few months. If not I'll look for something else.
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Winfried's posted video is informative and a great piece of marketing (NTTAWWT!) I was a bit surprised to hear the Brompton engineer insinuate they designed the CF fork and apparently are fabricating it at joint venture Brompton Fletcher Limited. Of course, I've only seen the internet pictures, but that fork sure looks like the one on the Hummingbird.
And BTW, why a CF fork when they've had a Ti fork in production for several years? Hmph.
Understood, but, with a wink and a nod, we are chatting about folding bikes. The British Whippet is a great folding bike...except for the fold.
And BTW, why a CF fork when they've had a Ti fork in production for several years? Hmph.
...except for the fold...
Understood, but, with a wink and a nod, we are chatting about folding bikes. The British Whippet is a great folding bike...except for the fold.

Last edited by tcs; 01-20-22 at 12:41 PM.
#17
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I'm extremely disappointed in the CF fork. I was expecting an all ti bike, this ain't that.
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If you commute and thus need a compact bike that's easy to fold/unfold, there's no contest.
Besides, the Brompton is well designed for what most people use it for: Riding a few kms/miles to/from the station.
https://www.youtube.com/watch?v=dJNte8yO-_A
Besides, the Brompton is well designed for what most people use it for: Riding a few kms/miles to/from the station.
https://www.youtube.com/watch?v=dJNte8yO-_A
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All criticism aside, this is a bike for people who have more money than they know what to do with. I wish I could say that for myself but that doesn't mean that Brompton did a poor job in planning this bike. I'm sure they looked out and saw the Asian market building full Titanium bikes and had to come up with an answer. This is certainly a better bike than the Chapter 3 bikes they have been producing. If there was ever an over priced Brompton it is that. If they could sell out of those models then this bicycle looks like a deal to me. Is there anyone here that would rather have a Chapter 3 or the T line. The next thing is going to be an electric P and T line. Unfortunately they couldn't figure out how to build a larger wheeled bike for those of us that want to ride in comfort. If the Moulton could fold I'd have one already. I'm tried of filling out Brompton's questionnaire asking for a bike with larger tires. I had a chance to purchase a NWT 8 speed with a thudbuster seatpost and Big Apple tires in like new condition for $1200 from Portapedal 4 years ago. Oh well.
Last edited by Pahana; 01-20-22 at 08:57 PM.
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I cannot believe they released the bike as is. The bike is a joke, even compared to Chinese clones released years ago.
-Thick main tubing and straight carbon fork totally ruining classic Brompton aesthetics. It looks more like chinese knockoff of dahon bikes rather than legit Brompton.
-Horrible welding lines everywhere. They couldn't fabricate the BB area the old way (precisely welding tubes and sheets) so they used separate cast BB manifold instead.
-As a result the titanium frame is almost as heavy as the steel frame. Brompton high tensile steel frame usually weighs around 2.1kg. They claim their titanium frame is 200 gram lighter. That is 1.9 kilograms.
For comparison, clone chromoly frames (which uses better material than the original one) weighs around 2.0kg, and clone titanium frames weigh around 1.3kg.
-They tried really hard to shave grams elsewhere. They even use ultralight (and ultra-fragile AFAIK) tubolito tubes to shave grams. I have never seen any stock bike that comes with tubolito tubes elsewhere.
And the proud 7.45kg weight is nothing to boast of. Just put titanium handlepost, lightweight niobium wheelset (available at $200) and lightweight tires and tubes on current superlight and you can very easily reach the same weight. After all the titanium frame is only 0.2kg lighter than steel one!
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Actually, both bike have a relatively heavy titanium frame and shaved weight using lightweight components.
If you look at the weight of the titanium frame Seattle Cycles Burke, its 8kg.
And my titanium Birdy factory equipped with relatively heavy components (only the carbon FSA SLK Light crankset is high end) has the same weight as the aluminum Birdy III.
So, we can wonder if a titanium frame is the way to go to get a very lightweight folder?
For the welding and frame tube finish, its probably to save cost on a UK made frame?
But for the thick main tube and carbon fork, I do not agree with you, I like it, it keeps the Brompton silhouette but with a more modern design.
And the thick stem could be stiffer than the thin steel stem that gives a big part of the frame flexibility of the steel frame that you feel when riding a Brompton.
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-Third party titanium main frame is approximately 35% lighter than the steel one (1.3kg vs 2.1kg)
A full titanium brompton frameset (third party main frame, fork, rear triangle, handlepost) is roughly 1.6kg lighter than a full steel brompton frameset.
Titanium IS the way to get a lightweight folder, for sure. They just messed up big time with T-line main frame.
#23
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Titanium is roughly 40% lighter than steel. In my opinion, unless it's used purely because of weight savings, ignoring other properties, it would make sence to pay premium for titanium only if you get weight savings around 35-40%. Definitely not for minuscule changes in weight to have titanium frame for the sake of it.
Last edited by CEBEP; 01-21-22 at 04:49 AM.
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-Brompton titaniuim fork and rear triangle (supposedly still made in russia) are approximately 40% lighter than the steel one. (Mine are 45% lighter, but they have a lot of weight variance between samples though)
-Third party titanium main frame is approximately 35% lighter than the steel one (1.3kg vs 2.1kg)
A full titanium brompton frameset (third party main frame, fork, rear triangle, handlepost) is roughly 1.6kg lighter than a full steel brompton frameset.
Titanium IS the way to get a lightweight folder, for sure. They just messed up big time with T-line main frame.
-Third party titanium main frame is approximately 35% lighter than the steel one (1.3kg vs 2.1kg)
A full titanium brompton frameset (third party main frame, fork, rear triangle, handlepost) is roughly 1.6kg lighter than a full steel brompton frameset.
Titanium IS the way to get a lightweight folder, for sure. They just messed up big time with T-line main frame.
But mechanical properties are also lower and different, so its not possible to use the same diameter and thickness of tubes than for steel tubes. And this is more true if the Ti is grade 9 and the steel an high end alloy.
So, the saving cannot be 40% of the weight of the steel frame. A Ti frame made with grade 9 titanium with the same diameter and thickness of the tubes as the steel frame will flex a lot and can break. There are several lightweight Ti bike frames that are very soft with a lack of stiffness and also frame that break (due also to oxygen contaminated welding that cause slow Ti corrosion).
Expert Ti frame manufacturers like Passoni use a mix of several titanium grade and triple butted Ti tubes to obtain a stiff enough and lightweight frame. But those butted tubes exists only for a classic diamond bike frame, not for a single tube main frame.
This is why Brompton enlarged the tubes diameters instead of just making a clone of the steel frame.
The Ti parts for the current P-line and T-line and previous Ti Brompton are since many years not made in Russia anymore but in UK, currently by CW Fletcher in Sheefield.
So all Brompton frames, steel and Ti, are 100% Made in UK.
About Ti for lightweight bike frames, the drawback of Ti is that Ti alloy didn't really evolve while carbon and steel alloy evolved a lot with as results that not only carbon frame can have better performance for he same or less weight but also steel frames in Columbus XCR or Reynolds 953 stainless steel can provide same weight with higher performances than titanium frames.
#25
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Out of curiosity, could Brompton have achieved the same weight reduction by using top-quality steel instead of hi-ten, and still sell it for ~$€̈£4,500?