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-   -   HOTNESS!!! 20" Custom Brompton,... (https://www.bikeforums.net/showthread.php?t=1209601)

tds101 08-07-20 09:35 AM

HOTNESS!!! 20" Custom Brompton,...
 
https://cimg2.ibsrv.net/gimg/bikefor...860054b124.jpg
https://cimg1.ibsrv.net/gimg/bikefor...6f69df65d8.jpg
https://cimg5.ibsrv.net/gimg/bikefor...c316a305fa.jpg

ImplodingVoice 08-07-20 11:53 AM

Link is unsecure / can't load web site.
Who modified, or put this bike together?
Thanks for sharing.

2_i 08-07-20 06:58 PM

Not sure here. Brompton has a wheelbase of 104.5cm, within the bracket for a full size bikes. Folders typically have a shorter wheelbase giving rise to a squirrelly handling. Now this 20" 'Brompton' seems to have a wheelbase of the order of 118cm, there to squeeze in the 20" into the folded size. This is well beyond the bracket employed for full size bikes, presumably resulting in a klutzy sluggish handling.

rhenning 08-08-20 03:27 PM

No it is not repaired. Roger

tds101 08-08-20 06:05 PM


Originally Posted by BikeLite (Post 21630359)

I just removed the links,...apparently it's considered unsafe for no real reason. :mad:

BikeLite 08-08-20 06:59 PM

they discrminate against non usa website apparently.

1. Internet search for the website name
2. Go to forum, page 23, Very Big Edition post

ttakata73 08-09-20 11:14 AM

Seems a long reach to the handlebars. Good for tall people but guessing by the seat angle that the rider is not tall.

fietsbob 08-09-20 09:10 PM

Stock Brompton. now, is about a 24" virtual top tube.. so, yea, that guy must be rather tall ..

Winfried 08-10-20 04:18 AM

Built by the famous Juliane Neuß.

"The wheel is a project for a rather large customer. " (per Google Translate)

https://cimg8.ibsrv.net/gimg/bikefor...f12f7d3b04.png

fietsbob 08-10-20 12:14 PM

Ah She (Juliane Neuß)
. of the Brompton recumbent Kit.
{My computer locked up using that link, so caution advised}




:innocent:

tds101 08-12-20 05:47 PM


Originally Posted by fietsbob (Post 21633504)
Ah She (Juliane Neuß)
. of the Brompton recumbent Kit.
{My computer locked up using that link, so caution advised}




:innocent:

The problem is there's absolutely NOTHING WRONG with that link. I can easily access it from another site (where I saw it in the first place). Totally ridiculous.

gilesa 08-14-20 03:00 AM


Originally Posted by tds101 (Post 21637950)
The problem is there's absolutely NOTHING WRONG with that link. I can easily access it from another site (where I saw it in the first place). Totally ridiculous.

My Firefox browser reports "Error code: SEC_ERROR_BAD_SIGNATURE" for the SSL certificate. Other browsers may be less explicit, but that seems like a real problem to me.

Edit: that was the forum link. The one directly above (for Neuss) shows:

Web sites prove their identity via certificates. Firefox does not trust this site because it uses a certificate that is not valid for www.junik-hpv.de. The certificate is only valid for chronos.space4rent.de.

Error code: SSL_ERROR_BAD_CERT_DOMAIN

Blackstrida_A_ 08-14-20 06:17 AM

Well...perhaps are the certificates not valid for the wrong spelling of the page address (with https: )?

What do your browsers tell you once the "s" was removed from the links (http: )?

Edit: Obviously, it is a forum "feature" - the software will add automatically an "s" after recognizing the letters h t t p and there is no way to avoid that.

tds101 08-14-20 11:22 AM


Originally Posted by gilesa (Post 21640214)
My Firefox browser reports "Error code: SEC_ERROR_BAD_SIGNATURE" for the SSL certificate. Other browsers may be less explicit, but that seems like a real problem to me.

Edit: that was the forum link. The one directly above (for Neuss) shows:

Web sites prove their identity via certificates. Firefox does not trust this site because it uses a certificate that is not valid for Human Power Vehicles | Spezialfahrräder. The certificate is only valid for chronos.space4rent.de.

Error code: SSL_ERROR_BAD_CERT_DOMAIN

When I used the link DIRECTLY FROM the UK forum where I saw the post I had no issues. Apparently it worked fine on Chrome, Edge, AND FIREFOX. Somehow the link is being modified when I post it, and it's no longer a valid, secure link. The one thing noted in FF is that the forum link isn't secure apparently. Here's the post in Cycle Chat

Now, it wasn't necessary to actually quote me, so can you not do it again,...unless you manage to find a way to share the link WITHOUT having it become invalid.

https://cimg5.ibsrv.net/gimg/bikefor...e5ad11da18.png

https://cimg5.ibsrv.net/gimg/bikefor...7d4e80bc96.jpg

BikeLite 08-14-20 11:23 AM

take the s off https and the website works..lmao

tds101 08-14-20 12:03 PM


Originally Posted by BikeLite (Post 21640863)
take the s off https and the website works..lmao

GOT IT!!! But, if you look at the "copy and paste" link, it's http, NOT https. It's just not being allowed. No biggie,... I love the Mega Brommie all the same. It just might be too big for me (I believe it's custom designed for a rider who's WAYYYY over 6' tall, and I'm 5'11"), but it still looks AMAZING!

Nyah 11-27-20 07:52 PM

https://cimg5.ibsrv.net/gimg/bikefor...c316a305fa.jpg
There's no reason that this bicycle couldn't be made
with a shorter toptube. Look how, in folded-mode,
the toptube of the 20" version is sticking out beyond the rear
wheel and compare it to where the TT of the 16" version ends.
The only reason that I can see for the extra length is to
accommodate the tall owner, not because the Brompton fold
system requires it.

If anyone sees that I'm wrong, please explain why. I don't own
a Brompton, have never even seen one in person.

tds101 11-29-20 01:49 PM


Originally Posted by Nyah (Post 21808889)
There's no reason that this bicycle couldn't be made
with a shorter toptube. Look how, in folded-mode,
the toptube of the 20" version is sticking out beyond the rear
wheel and compare it to where the TT of the 16" version ends.
The only reason that I can see for the extra length is to
accommodate the tall owner, not because the Brompton fold
system requires it.

If anyone sees that I'm wrong, please explain why. I don't own
a Brompton, have never even seen one in person.

If you would have read all the comments, etc, you'd see that it's a custom build for a "rather large" rider. That could be tall, big & tall, etc.

Nyah 11-29-20 10:56 PM


Originally Posted by tds101 (Post 21810713)
If you would have read all the comments, etc, you'd see that it's a custom build for a "rather large" rider. That could be tall, big & tall, etc.

You're confused. In my post, I acknowledged that the bicycle owner is tall. My post was addressing where someone implied that a 20" bicycle with the folding system that Brompton uses, would need to have an extra large frame.


Originally Posted by 2_i
Not sure here. Brompton has a wheelbase of 104.5cm, within the bracket for a full size bikes. Folders typically have a shorter wheelbase giving rise to a squirrelly handling. Now this 20" 'Brompton' seems to have a wheelbase of the order of 118cm, there to squeeze in the 20" into the folded size. This is well beyond the bracket employed for full size bikes, presumably resulting in a klutzy sluggish handling.

There's no reason that this bicycle couldn't be made
with a shorter toptube. Look how, in folded-mode,
the toptube of the 20" version is sticking out beyond the rear
wheel and compare it to where the TT of the 16" version ends.
The only reason that I can see for the extra length is to
accommodate the tall owner, not because the Brompton fold
system requires it.

If anyone sees that I'm wrong, please explain why. I don't own
a Brompton, have never even seen one in person.

2_i 11-29-20 11:34 PM


Originally Posted by Nyah (Post 21811394)
There's no reason that this bicycle couldn't be made
with a shorter toptube. Look how, in folded-mode,
the toptube of the 20" version is sticking out beyond the rear
wheel and compare it to where the TT of the 16" version ends.
The only reason that I can see for the extra length is to
accommodate the tall owner, not because the Brompton fold
system requires it.

If anyone sees that I'm wrong, please explain why. I don't own
a Brompton, have never even seen one in person.

The tolerances for having the bike still fold like a Brompton are very tight. The hook off the front wheel must grab the chainstay behind the pusher. To the extent that I can tell, the particular wheelbase is the shortest you can afford for that with the 20" wheels. For full-size bikes and most manufacturers the wheelbase changes very little with bike size. If you want, you can email Juliane and ask. Obviously if you want to build a bike from scratch, you can do whatever you want, but history has not brought in, so far, anything seriously competing with Brompton in the tightness of the fold against the bike's riding ability.

tds101 11-30-20 06:30 AM


Originally Posted by Nyah (Post 21811394)
You're confused. In my post, I acknowledged that the bicycle owner is tall. My post was addressing where someone implied that a 20" bicycle with the folding system that Brompton uses, would need to have an extra large frame.


There's no reason that this bicycle couldn't be made
with a shorter toptube. Look how, in folded-mode,
the toptube of the 20" version is sticking out beyond the rear
wheel and compare it to where the TT of the 16" version ends.
The only reason that I can see for the extra length is to
accommodate the tall owner, not because the Brompton fold
system requires it.

If anyone sees that I'm wrong, please explain why. I don't own
a Brompton, have never even seen one in person.

I'm not confused, and you're wrong. The bike posted here is sized for a larger rider, and is adjusted so it can fold exactly as any other Brompton. If you resize the top tube it would throw the fold out of whack. It appears to be just super-sized.

Bobinohio 11-30-20 09:14 AM

Love the concept of the folding bike you can take just about anywhere. I haven't seen one and every time I go to their website they're either sold out or have a very limited selection. Guessing I'll have to wait until post covid

Nyah 11-30-20 12:07 PM


Originally Posted by 2_i (Post 21811415)
The tolerances for having the bike still fold like a Brompton are very tight. The hook off the front wheel must grab the chainstay behind the pusher. To the extent that I can tell, the particular wheelbase is the shortest you can afford for that with the 20" wheels. For full-size bikes and most manufacturers the wheelbase changes very little with bike size. If you want, you can email Juliane and ask. Obviously if you want to build a bike from scratch, you can do whatever you want, but history has not brought in, so far, anything seriously competing with Brompton in the tightness of the fold against the bike's riding ability.

By "pusher" do you mean pedal? The position of the front wheel can be accommodated by adding-to/subtracting-from, the toptube, on each side of the hinge in equal amounts. For instance, if 3" were subtracted from the toptube on each side of the hinge, the front wheel would still contact the chainstay in the same location, even though the TT is now 6" shorter. Perfectly do-able, you just have to subtract equal amounts.

2_i 11-30-20 12:31 PM


Originally Posted by Nyah (Post 21812014)
By "pusher" do you mean pedal? The position of the front wheel can be accommodated by adding-to/subtracting-from, the toptube, on each side of the hinge in equal amounts. For instance, if 3" were subtracted from the toptube on each side of the hinge, the front wheel would still contact the chainstay in the same location, even though the TT is now 6" shorter. Perfectly do-able, you just have to subtract equal amounts.

Pusher is a simple derailleur employed on Brompton and located underneath the chainstay, that ends up pointing upwards upon folding. Basically the fold of Brompton and its locking are such that any increase in wheel diameter, including the maximal tire width, must add to the wheelbase. This is exactly what is encountered here as the wheelbase increases by about 5". Can you get around that? Yes, if you change details of the locking of the fold. However, then you throw in some potentially flaky elements that can come back to haunt you in the future. It depends what your priorities are, how much effort, time and money, the design and its execution will take. Everybody is free to design and make their own bike. I was commenting on the bike as it was made.


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