I've had a Brompton for the last 10 months and it's opened up my horizons and my life. Today I fitted a very lovely water bottle mechanism and tomorrow I'm going out for a very nice ride around some local lakes.
Always wanted a Brompton, but I agree that price point is stopping most of us from owning one. I'll personally stick with my $200 Stumpjumper I restored.
I would absolutely love to own a Brompton or something that folds into a similarly small size for when I travel by train, as rare as it is, and for a couple other things where the small package makes it a lot easier to store than my current main bicycle with 28 inch wheels. But I can buy no less than ten regular bicycles and simpler folders (used, not new, of course) for the price of one used Brompton, and I don't even live in the UK, so they're even more expensive.
@@elu9780 Here's the thing though: I've had no less than than 12 bikes since buying a Brompton. Only the Brompton has stayed. I think what some of us eventually realize is that it's worth spending more for the thing you really want. Especially for a bike that, unlike others, is extremely unlikely to ever get stolen. I've seen many Brompton owners essentially echo this sentiment.
It took me so long to be able to afford a Brompton, but I did finally manage it (I'm nearly 60) and it's the greatest thing I own. Just saying, don't give up the dream. 😅
I have other Brompton's and picked a Trailwhite G line on the first day they were available for public sale. Very happy with it so far. Wider when folded than my other Brompton's and a little longer.
I’ve owned a Brompton S6L for 4 years and love it, I’ve also recently bought a Moulton TSR so I don’t really need a bike that’s half way between the two… but I really want one! Good review, thanks 👍
I built mine for less than $700 + $800 for the A line I purchased 2 years ago. All parts were sourced in Singapore, the front fork and rear triangle were Chinese titanium. The bike weights less than the A line.
Loved your review. Now had Brompton brought this out 3 years ago when I urgently needed a BIG BURLY fold-up bike, I would have bought it. But instead I bought a super nifty TERN VERGE P10, and what a great bike this turned out to be. Now I'm hooked on it. But, I do love the look of this new G-Line from Brompton. Maybe I'll consider a second hand one, at some point.
They should have had a belt drive system on the G- Line , that would have really made the choice a lot easier and many more would have no doubts at all .
@@alexcarter8807 No but it is rather practical when having to service it! I would never want a belt, as I have had one on a bike years ago. Only with a onesided mount in the back. And the chain is inside the bike when folded, so it isn't any problem at all.
@@angus7979 Not sure if they do or not but they have belt drives for many types of Brompton bikes with their own rear triangle and forks with several options of different sizes of wheels , but their options are quite vast , probably wouldn’t be surprised if they have an idea for a belt drive for the G- Line , much more open to the future than the Brompton company.
I wanted an easier way to fly with my bike and cycle camp, I wasn't up for spending brompton money . I bought a 2nd hand dahon which after I found it to be so comfortable and worked for me fitted the same hub gears. It;s also got 20" wheels , I have a normal rack on the back and use my carradice paniers I'm sure bromptons are great but I think these are a good quality alternative.
Great video, I am a fat bloke with a campervan so I think the Gline is going to tick the boxes for me. Small footprint and capable of taking a bulky boy on grass and a bit of gravel
I found this video pretty helpful and informative! Two things - Have you attempted to take this in public transit yet? How does it stack up to a full gravel bike?
Think it’s their nicest looking to date. Steering tube, riser bars, fork and tires look really good. Perhaps an eventual dedicated Rohloff hub! I’ve seen the great Rohloff customs and always wanted one. But they’d be bloody expensive
I got one two weeks ago and love it. However, I have been riding a Brompton for 8 years so I’m used to them but wanted a folding bike that could cover more ground in greater comfort. The downside is the G-Line doesn’t have the edge over competition that the 'normal' Bromptons have - fold size - but I don’t commute everyday now and it still fits under the stairs, so all good for my needs.
It's hard to comment because I have never riding one. I feel this bike makes the brompton less niche and more versatile. As well as the benefits of a city commuter, it looks like it has the added benefits of using it on a canal towpath or a woodland area with relative comfort. The price is bonkers, but I feel you get a little bit more for your money with this one. Because of that, this G line is only brompton I would consider buying if I had the dosh.
I went to try one today. Didn’t like it, it’s not a Brompton. It’s a big spongey bike, very comfy and the disc brakes are nice. Great for off-road but not a city/commuter bike. I’ll stick to my P-Line and mountain bike, also save the £2500!!😊
If you like the G-Line you should definitely check out the Vello Gravel!! I havent tried the brompton G-line yet but i think it comes really close to the Vello Gravel
I bought my Brompton three years ago and i ride it wherever i go: to work, restaurants, even the doctors office. So when i heard about the new G-Line i knew i had to try it i just didn‘t have the time yet. Which handlebar Type did you ride?
"... Bromptons don't really get stolen...". Yes they do, lots. People get robbed for them whilst out riding, because they are expensive. This is very common - literally one of the most robbed bikes. I saw one that had just been stolen being ridden through Hackney last week. They are a target.
The point being made is Bromptons don't like being stored outdoors. But yes, your point about people being mugged for their bikes is valid and has been raised with Brompton especially around their Hire bikes where casual users may be less aware of these associated risks.
So, I don't have a Brompton, I have an old 16in wheel Dahon. I know what you mean about the twitchiness though. My Dahon's front geo is similar to a Brompton and it is twitchy but once I got a feel for it I have started to really enjoy riding it places it "shouldn't" go, like dirt and gravel paths
Have to agree on the twitchiness of riding the classic Brompton - and I think a single internal hub like the Alfine 8 or 11 is a better solution than the proprietary gearing on some Bromptons. Time will tell, but I think you've identified the vagueness of the target market. Personally, the attraction for me would be ease of transport compared to a full-sized bike. Just chuck it in the boot of the car and take it somewhere. I also imagine it would be easier to bring it into hotels, B&Bs, hostels, etc., who might object to you keeping a full-sized bike in your room. And, as you said, perfect for people holidaying in camper vans.
The original Brompton uses a very narrow hub, originally specially made by Sturmey Archer. And you buy a Brompton for its fold and not for its ride. My former 2019 Superlight is now down to below 9 kilo, with mudguards. Not much from the original bike is still left, I admit. Finn. Denmark
It’s truly for whoever is running the equivalent of 2nd Life Bikes in 20 years time. Look what I found at the Co-op or whatever online marketplace. Then said person in the future can put a mishmash of parts from BMX and mountain bikes and then just before the build is finished they realise they need a proprietary part from Brompton that costs the price of the whole project so they swap it with a mate for a full size bike.
"Brompton did not send me this bike so this is possibly the only honest review so far". Good to know. I'll remember that about products that you received for free.
I meant only honest Brompton review. But I hear what you mean. I can confirm though, I have never read a script (it would be very obvious 😂) and I only ever say things I mean. Pinky promise.
Niche is the word mate! I bought a Dahon Dash 18 some 10 years ago as a school runner needing to go on the metro. I still have it but didn't need to take the metro as of 5 years ago. During its main use I came off it at least once a week! I blame the wheels, 20", they really lost the gyro effect, especially on leaves and wet roads, not to mention the terrible impact with pot holes! The bike cost €800 new and it still has its occasional uses but no way would I dish out a couple of grand on one, even with chunkier tyres... its not my "niche" 😄
Haven't been able to find, but what is the axle space situation on this Brompton? The normal ones are kind of weird, but I assume this being disc brake it's 100/135 mm?
Holy smokes you can a propper bike for that money. I guess its the right price if you really, really, reeeealy need one :D hehe. If a train, subway, buss or tram is a part of you commute in Norway, this would make sense if it fits the rules for packable size to be allowed on the buss, train, subway to bring as carry on.
Is the G Line really "more niche" than a 16-inch Bromton? I don't think so. There are very few 16-inch folding bikes. There are a lot of 20-inch folding bikes. And if you take the mudguard off and put other tires on, it's also "Gravel". I'm also curious to see how the G Line will fare against the many other 20-inch bikes on the market. Will people buy it who found the 16-inch Bromptons too small? Or will they prefer Dahon, Tern, Birdy, etc.?
I just can’t justify the cost for something that’s so niche? Most of commuting is done on a bike I’ve put in about $150 in the two years I’ve owned it. If it gets stolen, broken, it’s no sweat. I just can’t imagine using the g-line enough. Would it be cool for travelling? Yes but I can rent a bike on a dozen trips for less $$$ with no maintenance. Maybe if I had a bunch of $$$ burning a hole in my pocket but it’s a bit niche for me personally. With no multimodal commute anymore.
I bought a 2spd c-line just as the g dropped and I did consider it but it’s almost too much bike for what brom is supposed to be imo. Coming from the fixed gear scene and only getting a brom because I’ve moved to a flat the g seemed perfect as my c will never see a train but there’s something utilitarian about the c that I love, the gearing is spot on coming from high ratio fixies and road bikes, the handling is twitchy but so are track and race bikes. I can see why you prefer the g though as you’re m/atb focused but the wider bars are slower handling take away from what I love about my c, filtering and weaving through traffic is amazing
Not being sure what to say is cool. You don't have to have a hot take. Having mixed feelings is cool. I've never had a Brompton, but I love the concept ... but I feel they're not for me. So ... same-same.
It's a Brompton in name only. Most parts on the G are manufactured abroad. The inflated price is way too much for a folder with hub gears, fat tyres and a weight penalty of 15 kg +.
Because it looks cool. Er, probably because the Sturmey-Archer hub in the back has a fixed gearing so the gear on the front determines how high the gears are. It might not even be that big, just looks big on a Brompton.
It's because the wheels are so small. Basic mechanics, if you look up terms like "gear inches," but imagine cutting a 700c tire and laying it out like a snake, that's the distance you travel with one wheel revolution and the amount of work your legs have to do. A 16" tire moves you only about half as far. So imagine everything else (rear cassette/gear size etc) is the same, you'd want twice as big a chainring on a Brompton to make it equal out so that you do the same number of pedal strokes to go the same distance and speed. Put a tiny 1x mtb chainring on a Brompton, and you'd spin out going 10mph.
I live in a 90+% car free city. Pretty much everything here is made for bicycles,but due to its medieval nature, there are still a couple of cobblestone parts. A brompton is a total death bike in this city and they are waaaay too overpriced. Me personally a, say, full suspension R&M Birdy R 20 is much much better value. Even the regular Birdies with 18 inch wheels can prolonge your life compared to a regular Brompton. And as far as customization goes. Brompton comes nowhere near. Btw, far from comparing, but you can get an electric, carbon, 12 kg ADO for half the price . And as far as quick folding, commuter goes.....get a Btwin one second Fold. No seriously, a Tern BYB is better value than this fanboy antique in a new jacket.
You don't buy a Brompton for its ride but for its fold! And a G-line fills and weighs more! My much modified 2019 Superlight now weighs below 9 kilo, but as a "bike" it is a horrible and heavy roling contraption! OK, I like it anyway. Finn. Denmark
I've had a Brompton for the last 10 months and it's opened up my horizons and my life. Today I fitted a very lovely water bottle mechanism and tomorrow I'm going out for a very nice ride around some local lakes.
I got one. Great fun. Can't argue about it's a bit of a chunker but blimey, it's fun to ride. Perfect on a very narrow canal path. 😊
Always wanted a Brompton, but I agree that price point is stopping most of us from owning one. I'll personally stick with my $200 Stumpjumper I restored.
I would absolutely love to own a Brompton or something that folds into a similarly small size for when I travel by train, as rare as it is, and for a couple other things where the small package makes it a lot easier to store than my current main bicycle with 28 inch wheels. But I can buy no less than ten regular bicycles and simpler folders (used, not new, of course) for the price of one used Brompton, and I don't even live in the UK, so they're even more expensive.
@@elu9780 Here's the thing though: I've had no less than than 12 bikes since buying a Brompton. Only the Brompton has stayed.
I think what some of us eventually realize is that it's worth spending more for the thing you really want. Especially for a bike that, unlike others, is extremely unlikely to ever get stolen. I've seen many Brompton owners essentially echo this sentiment.
It took me so long to be able to afford a Brompton, but I did finally manage it (I'm nearly 60) and it's the greatest thing I own. Just saying, don't give up the dream. 😅
How much does a used Brompton cost , then?!?@@elu9780
To me it feels like the bmx I was riding when I was a kid, and it is great!
I have other Brompton's and picked a Trailwhite G line on the first day they were available for public sale. Very happy with it so far. Wider when folded than my other Brompton's and a little longer.
I’ve owned a Brompton S6L for 4 years and love it, I’ve also recently bought a Moulton TSR so I don’t really need a bike that’s half way between the two… but I really want one!
Good review, thanks 👍
I built mine for less than $700 + $800 for the A line I purchased 2 years ago. All parts were sourced in Singapore, the front fork and rear triangle were Chinese titanium. The bike weights less than the A line.
Do you have a link to the parts in Singapore?
I have seen recently that Litepro are selling a new Brompton clone (Litepro S6) which weight 8 kg for 1k$
You missed the opportunity to show them next to each other to compare sizes. Both open and folded.
Loved your review. Now had Brompton brought this out 3 years ago when I urgently needed a BIG BURLY fold-up bike, I would have bought it. But instead I bought a super nifty TERN VERGE P10, and what a great bike this turned out to be. Now I'm hooked on it. But, I do love the look of this new G-Line from Brompton. Maybe I'll consider a second hand one, at some point.
They should have had a belt drive system on the G- Line , that would have really made the choice a lot easier and many more would have no doubts at all .
A beltdrive? Why I can't see any profits by that except problems when changing wheel, as you need a different frame. You can't open a belt.
@@finncarlbomholtsrensen1188 Who opens their chain when changing a wheel?
@@alexcarter8807 No but it is rather practical when having to service it! I would never want a belt, as I have had one on a bike years ago. Only with a onesided mount in the back. And the chain is inside the bike when folded, so it isn't any problem at all.
Kinetics make a belt-drive kit for the G line.
@@angus7979 Not sure if they do or not but they have belt drives for many types of Brompton bikes with their own rear triangle and forks with several options of different sizes of wheels , but their options are quite vast , probably wouldn’t be surprised if they have an idea for a belt drive for the G- Line , much more open to the future than the Brompton company.
I wanted an easier way to fly with my bike and cycle camp, I wasn't up for spending brompton money . I bought a 2nd hand dahon which after I found it to be so comfortable and worked for me fitted the same hub gears. It;s also got 20" wheels , I have a normal rack on the back and use my carradice paniers I'm sure bromptons are great but I think these are a good quality alternative.
Great video, I am a fat bloke with a campervan so I think the Gline is going to tick the boxes for me. Small footprint and capable of taking a bulky boy on grass and a bit of gravel
I found this video pretty helpful and informative!
Two things - Have you attempted to take this in public transit yet?
How does it stack up to a full gravel bike?
Think it’s their nicest looking to date. Steering tube, riser bars, fork and tires look really good. Perhaps an eventual dedicated Rohloff hub! I’ve seen the great Rohloff customs and always wanted one. But they’d be bloody expensive
Such good and reasonable information, I really appreciate your channel.
I got one two weeks ago and love it. However, I have been riding a Brompton for 8 years so I’m used to them but wanted a folding bike that could cover more ground in greater comfort. The downside is the G-Line doesn’t have the edge over competition that the 'normal' Bromptons have - fold size - but I don’t commute everyday now and it still fits under the stairs, so all good for my needs.
It's hard to comment because I have never riding one. I feel this bike makes the brompton less niche and more versatile. As well as the benefits of a city commuter, it looks like it has the added benefits of using it on a canal towpath or a woodland area with relative comfort. The price is bonkers, but I feel you get a little bit more for your money with this one. Because of that, this G line is only brompton I would consider buying if I had the dosh.
One of the things for me is that you can put it in the car and take it to places you would not normally ride.
I live in NJ USA. Unfortunately it’s not available in the US until next year. I’m eager to get one.
i didnt like my 6 speed c line at first. I replaced the squishy shock absorber with a very hard racing one and it is a joy to ride.
Go on, get one! I have 3 Bromptons but now I have to test ride a G line and think up excuses to acquire one.
Great honest video... I've got two on order.. One for my wife the other for me!
Great vid, spotted because of my interest in a Brompton, will watch more of ya vids as enjoyed that…. Cheers :)
I went to try one today. Didn’t like it, it’s not a Brompton.
It’s a big spongey bike, very comfy and the disc brakes are nice. Great for off-road but not a city/commuter bike. I’ll stick to my P-Line and mountain bike, also save the £2500!!😊
If you like the G-Line you should definitely check out the Vello Gravel!! I havent tried the brompton G-line yet but i think it comes really close to the Vello Gravel
I bought my Brompton three years ago and i ride it wherever i go: to work, restaurants, even the doctors office. So when i heard about the new G-Line i knew i had to try it i just didn‘t have the time yet. Which handlebar Type did you ride?
I tried one last weekend at our Brompton dealer. It is a frwam to ride. It really feels like a 28 inch wheel bike when riding it.
"... Bromptons don't really get stolen...". Yes they do, lots. People get robbed for them whilst out riding, because they are expensive. This is very common - literally one of the most robbed bikes. I saw one that had just been stolen being ridden through Hackney last week. They are a target.
correct, care needed where you ride one in certain parts of London
The point being made is Bromptons don't like being stored outdoors.
But yes, your point about people being mugged for their bikes is valid and has been raised with Brompton especially around their Hire bikes where casual users may be less aware of these associated risks.
Most people in the US have no idea what it is. I guess that's an advantage. 😅
I like it but Isince i don't have a brompton, i'll continue commuting on my zizzo forte, ordered a zizzo liberte yesterday.
Craig with the calf flex. 😂 🦵
So, I don't have a Brompton, I have an old 16in wheel Dahon. I know what you mean about the twitchiness though. My Dahon's front geo is similar to a Brompton and it is twitchy but once I got a feel for it I have started to really enjoy riding it places it "shouldn't" go, like dirt and gravel paths
I took a test ride at a shop here in Antwerp. I’m going to get the electric one
Have to agree on the twitchiness of riding the classic Brompton - and I think a single internal hub like the Alfine 8 or 11 is a better solution than the proprietary gearing on some Bromptons.
Time will tell, but I think you've identified the vagueness of the target market. Personally, the attraction for me would be ease of transport compared to a full-sized bike. Just chuck it in the boot of the car and take it somewhere. I also imagine it would be easier to bring it into hotels, B&Bs, hostels, etc., who might object to you keeping a full-sized bike in your room. And, as you said, perfect for people holidaying in camper vans.
The original Brompton uses a very narrow hub, originally specially made by Sturmey Archer. And you buy a Brompton for its fold and not for its ride. My former 2019 Superlight is now down to below 9 kilo, with mudguards. Not much from the original bike is still left, I admit. Finn. Denmark
Your Bootleg Sticker Pack #2 just arrived yesterday, thanks!
It’s truly for whoever is running the equivalent of 2nd Life Bikes in 20 years time. Look what I found at the Co-op or whatever online marketplace. Then said person in the future can put a mishmash of parts from BMX and mountain bikes and then just before the build is finished they realise they need a proprietary part from Brompton that costs the price of the whole project so they swap it with a mate for a full size bike.
"Brompton did not send me this bike so this is possibly the only honest review so far". Good to know. I'll remember that about products that you received for free.
I meant only honest Brompton review. But I hear what you mean.
I can confirm though, I have never read a script (it would be very obvious 😂) and I only ever say things I mean.
Pinky promise.
Niche is the word mate! I bought a Dahon Dash 18 some 10 years ago as a school runner needing to go on the metro. I still have it but didn't need to take the metro as of 5 years ago. During its main use I came off it at least once a week! I blame the wheels, 20", they really lost the gyro effect, especially on leaves and wet roads, not to mention the terrible impact with pot holes! The bike cost €800 new and it still has its occasional uses but no way would I dish out a couple of grand on one, even with chunkier tyres... its not my "niche" 😄
Brompton, make a titanium version (GT line?), and I'm buying.
I want to get my first Brompton and they are not cheap. P line or G line?
The issue i have with it is it weighs as much as some 20 inch filding ebikes!
Haven't been able to find, but what is the axle space situation on this Brompton? The normal ones are kind of weird, but I assume this being disc brake it's 100/135 mm?
You have the slightly disturbed air of someone who has just discovered they're bro' curious.
My challenge Holborn from argos is the best folder but that brompton aint too bad 😂 id never say no to one.
Holy smokes you can a propper bike for that money. I guess its the right price if you really, really, reeeealy need one :D hehe. If a train, subway, buss or tram is a part of you commute in Norway, this would make sense if it fits the rules for packable size to be allowed on the buss, train, subway to bring as carry on.
Is the G Line really "more niche" than a 16-inch Bromton?
I don't think so.
There are very few 16-inch folding bikes. There are a lot of 20-inch folding bikes. And if you take the mudguard off and put other tires on, it's also "Gravel". I'm also curious to see how the G Line will fare against the many other 20-inch bikes on the market. Will people buy it who found the 16-inch Bromptons too small? Or will they prefer Dahon, Tern, Birdy, etc.?
if I start saving now, maybe I can get one when I'm 40
Wow!, that’s a long time.
I just can’t justify the cost for something that’s so niche? Most of commuting is done on a bike I’ve put in about $150 in the two years I’ve owned it. If it gets stolen, broken, it’s no sweat.
I just can’t imagine using the g-line enough. Would it be cool for travelling? Yes but I can rent a bike on a dozen trips for less $$$ with no maintenance.
Maybe if I had a bunch of $$$ burning a hole in my pocket but it’s a bit niche for me personally. With no multimodal commute anymore.
just got mine yesterday
What’s your verdict??
@@2NDLIFEBIKES i need a bit more time on that bike to give a verdict, will get back to this after 1 month
@@2NDLIFEBIKES the ride is so smooth and comfortable, i think the bike is legit
Club? It’s a CULT! 😂
I bought a 2spd c-line just as the g dropped and I did consider it but it’s almost too much bike for what brom is supposed to be imo.
Coming from the fixed gear scene and only getting a brom because I’ve moved to a flat the g seemed perfect as my c will never see a train but there’s something utilitarian about the c that I love, the gearing is spot on coming from high ratio fixies and road bikes, the handling is twitchy but so are track and race bikes.
I can see why you prefer the g though as you’re m/atb focused but the wider bars are slower handling take away from what I love about my c, filtering and weaving through traffic is amazing
Not being sure what to say is cool. You don't have to have a hot take. Having mixed feelings is cool. I've never had a Brompton, but I love the concept ... but I feel they're not for me. So ... same-same.
I WAS buying a brompton !
Then tured away and bought a thousand quid XC hardtail 😂 its been great ! Hardwork on the comute ! But who cares ay !
Should we call this an atBrompton?
OMG! 🤯
great
This bike is pointless. It's too big and heavy to be portable and if you want to ride off road you wouldn't choose a folding bike.
Why would anybody want to commuteon wet and greasy roads busy with traffic on a bike like that with tiny wheels ? Thats suicide !!!!
I can’t believe you don’t like Brompton’s ,,,,,you already have the tash for it
Too heavy for a folding bike.
It's a Brompton in name only. Most parts on the G are manufactured abroad. The inflated price is way too much for a folder with hub gears, fat tyres and a weight penalty of 15 kg +.
I have no need for a Brompton, but I am curious as to why they seem to always have such a large chainring up front.
Because it looks cool. Er, probably because the Sturmey-Archer hub in the back has a fixed gearing so the gear on the front determines how high the gears are. It might not even be that big, just looks big on a Brompton.
It's because the wheels are so small. Basic mechanics, if you look up terms like "gear inches," but imagine cutting a 700c tire and laying it out like a snake, that's the distance you travel with one wheel revolution and the amount of work your legs have to do. A 16" tire moves you only about half as far. So imagine everything else (rear cassette/gear size etc) is the same, you'd want twice as big a chainring on a Brompton to make it equal out so that you do the same number of pedal strokes to go the same distance and speed. Put a tiny 1x mtb chainring on a Brompton, and you'd spin out going 10mph.
Looks like grown man riding his kids bike !
I live in a 90+% car free city. Pretty much everything here is made for bicycles,but due to its medieval nature, there are still a couple of cobblestone parts. A brompton is a total death bike in this city and they are waaaay too overpriced. Me personally a, say, full suspension R&M Birdy R 20 is much much better value. Even the regular Birdies with 18 inch wheels can prolonge your life compared to a regular Brompton. And as far as customization goes. Brompton comes nowhere near. Btw, far from comparing, but you can get an electric, carbon, 12 kg ADO for half the price . And as far as quick folding, commuter goes.....get a Btwin one second Fold. No seriously, a Tern BYB is better value than this fanboy antique in a new jacket.
Too expensive and not as useful as the normal brompton. Can get a different folder thats half the price and folds same size.
You don't buy a Brompton for its ride but for its fold! And a G-line fills and weighs more! My much modified 2019 Superlight now weighs below 9 kilo, but as a "bike" it is a horrible and heavy roling contraption! OK, I like it anyway. Finn. Denmark