Go Back  Bike Forums > Bike Forums > Folding Bikes
Reload this Page >

Brompton: Replacing the M-Bar with an S-Bar

Search
Notices
Folding Bikes Discuss the unique features and issues of folding bikes. Also a great place to learn what folding bike will work best for your needs.

Brompton: Replacing the M-Bar with an S-Bar

Thread Tools
 
Search this Thread
 
Old 03-26-11 | 07:15 AM
  #1  
Thread Starter
Senior Member
20 Anniversary
 
Joined: Jun 2002
Posts: 313
Likes: 0
From: GTA, Canada
Brompton: Replacing the M-Bar with an S-Bar

I just got a Brompton M6R and have begun using it to commute to work. It has been great except that I feel the position is too upright for me. I am now thinking of converting the M-Bar to an S-Bar. I won't be replacing the "M" stem which I understand is shorter than that on "S" series. This suits me just fine as I am used to riding road bikes.

My question is will the brake and shifter cables need replacing too?
cyclocommuter is offline  
Reply
Old 03-26-11 | 08:27 AM
  #2  
PDR
Senior Member
 
Joined: Jan 2008
Posts: 575
Likes: 2
From: Cheshire, North West England, UK

Bikes: Brompton S2L-X, Bridgestone Moulton, 1963 & 1966 Moultons, Scott Mountain bike

The current cables would be too long for this conversion and so would the S-Type cables as you would be setting the handle bar lower than they are even on an S-Type. You might after some careful measuring be able to cut down the existing cables to suit.

I have a bespoke S-Type and love the riding position.... I also bought my Dad a Brompton... he wanted an S-Type but none of the dealers had one in stock and he wanted one there and then (he just will not wait haha)....I looked at doing the conversion from M to S and to do it properly you need the S-Type handlebars, stem, cables and I think IIRC also the brake levers.

Last edited by PDR; 03-28-11 at 02:47 PM. Reason: typo
PDR is offline  
Reply
Old 03-26-11 | 10:04 AM
  #3  
Thread Starter
Senior Member
20 Anniversary
 
Joined: Jun 2002
Posts: 313
Likes: 0
From: GTA, Canada
PDR, thanks for the insight. I just ordered the S-bar online and what I might do is try it out first on my bike and see if it fits on my M-stem. I don't see the S-type stem available online (NYCEWheels) but as I said if the S-bar fits I will probably stick to my M-stem since it makes for an even lower riding position which I prefer for medium to loner range riding. I might just cut the existing cables as you suggested.
cyclocommuter is offline  
Reply
Old 03-26-11 | 10:32 AM
  #4  
Mr. Fly's Avatar
Senior Member
 
Joined: Jan 2007
Posts: 662
Likes: 2
From: Silicon Valley, CA.
The Brompton handlebars are not custom-sized. You can use just about any non-oversized MTB bar that has the 25.4mm stem clamp. I mocked up a M-stem with an old Bontrager Ti handlebar and PDR is correct in that the cable housings needed trimming. However, that's not hard if you're handy around the bike. The handlebar may also need to trimmed for length, so that it doesn't affect the fold.
Mr. Fly is offline  
Reply
Old 03-26-11 | 11:27 AM
  #5  
Banned
 
Joined: Jun 2010
Posts: 43,586
Likes: 1,380
From: NW,Oregon Coast

Bikes: 8

This looks like a good piece,https://www.thorusa.com/dahon/technical/aberhallo.htm
So bar not so low, when not getting the rest of the S bar setup..
Which is available if you ask the right question, allow domestic dealer order/ship delay..
Or, want to just click over the web? Retail import from UK? https://www.sjscycles.co.uk/brompton-...att-prod20013/

Last edited by fietsbob; 03-26-11 at 07:48 PM.
fietsbob is offline  
Reply
Old 03-26-11 | 07:41 PM
  #6  
Thread Starter
Senior Member
20 Anniversary
 
Joined: Jun 2002
Posts: 313
Likes: 0
From: GTA, Canada
Thanks for the feedback folks... I will update this thread when I get the M-bar replaced with the S-bar.
cyclocommuter is offline  
Reply
Old 03-31-11 | 12:42 PM
  #7  
SesameCrunch's Avatar
Eschew Obfuscation
 
Joined: Aug 2005
Posts: 3,845
Likes: 0
From: San Francisco Bay Area

Bikes: 2005 Fuji Professional, 2002 Lemond Zurich, Folders - Strida, Merc, Dahon, Downtube, Recumbent folder

Question: does the S type stem give you more top tube reach as well? Or just lower height?
__________________
SesameCrunch is offline  
Reply
Old 03-31-11 | 12:57 PM
  #8  
Banned
 
Joined: Jun 2010
Posts: 43,586
Likes: 1,380
From: NW,Oregon Coast

Bikes: 8

the Mast , stem, for the S bar is taller than the M bar ,
and the S bar mast has a bend in it , so bar clamp further forward.
but the bar, as it has no rise , will be lower,
so only using the lower S bar front bag won't interfere with the steering,
and braking.
brake levers being the lowest contact point.

Last edited by fietsbob; 03-31-11 at 01:01 PM.
fietsbob is offline  
Reply
Old 04-04-11 | 03:32 AM
  #9  
Newbie
 
Joined: May 2009
Posts: 4
Likes: 0


hi all, i actually did this mod on my bike. took my original M-type to the local brompton dealer and asked them to install the S bar instead. size is the same, no issues with length and even with added grips and bar ends, the fold was not affected. all the cables did have to be cut down to length though.
Attached Images
File Type: jpg
b1.jpg (47.2 KB, 559 views)
ansikutero is offline  
Reply
Old 04-04-11 | 09:57 AM
  #10  
Thread Starter
Senior Member
20 Anniversary
 
Joined: Jun 2002
Posts: 313
Likes: 0
From: GTA, Canada
Nice to know this ansikutero. The S-bar I ordered will be arriving today. Instead of cutting the existing cables, I intend to just get new ones for the S-bar. In case I decide to put the M-bars back I will still have the original cables.

What model of Ergon grips/barends are those in your pic? They look nice. Can you still fold the bike without adjusting/twisting the Ergon grips/barends?
cyclocommuter is offline  
Reply
Old 04-11-11 | 01:59 AM
  #11  
Newbie
 
Joined: May 2009
Posts: 4
Likes: 0
Originally Posted by cyclocommuter
What model of Ergon grips/barends are those in your pic? They look nice. Can you still fold the bike without adjusting/twisting the Ergon grips/barends?
The grips are Ergon GX2's with magnesium bar-ends. I needed proper grips and this was the only one available at the shop at the time. They don't affect the fold as the bars rest on either side of the folded wheel.



The only issue I've had with them is that they're long, and the stock Brompton brake levers have a plastic wedge that doesn't let you align the levers to the edge of the grips. (You can see what I'm talking about from the picture I posted.)



For someone with shorter hands like myself, it's a pain trying to shift gears. Originally, the plastic wedge was over the original foam grips. Other people have ended up cutting their grips to make way for the ledge, or you could buy shorter grips meant for grip-shifters. I like these grips too much to give them up so I ended up changing the brake levers for Shimano R770's instead.

Last edited by ansikutero; 04-11-11 at 02:08 AM.
ansikutero is offline  
Reply
Old 04-11-11 | 04:35 PM
  #12  
Thread Starter
Senior Member
20 Anniversary
 
Joined: Jun 2002
Posts: 313
Likes: 0
From: GTA, Canada
Thanks for the followup. My S-bar arrived last week and I am about to place an order online for Ergon GR2s. I understand the "plastic wedge" issue that you pointed out and this is the reason I am still wondering if I should order the shorter "grip shift" version of the GR2s. However I might just get the regular version, try them out, then cut off an inch or so from the inside if it interferes with shifting.
cyclocommuter is offline  
Reply
Old 04-11-11 | 04:47 PM
  #13  
Senior Member
 
Joined: Jul 2008
Posts: 1,984
Likes: 1

Bikes: Brompton, Dahon Vitesse D5

I'd be tempted to switch the brake levers out for Shimano BL-R550 / 770 to get an extra bit of space. . . and because they look nice.
chagzuki is offline  
Reply
Old 04-11-11 | 06:08 PM
  #14  
14R's Avatar
14R
Bromptonaut
 
Joined: Feb 2005
Posts: 1,736
Likes: 2
From: Jersey City, NJ

Bikes: 1994 Diamond Back Racing Prevail ti; Miyata 914, Miyata 1000, 2017 Van Nicholas Chinook

I have an extra S-Type bar (recently upgraded my original to a Ti version of similar angle). Just PST me if interested.
14R is offline  
Reply
Old 04-11-11 | 08:50 PM
  #15  
Banned
 
Joined: Jun 2010
Posts: 43,586
Likes: 1,380
From: NW,Oregon Coast

Bikes: 8

Pondering on S type riser stem + aber hallo + MTB riser bar to get me back to M bar height,
but not have the big u in the middle, and maybe a bit more angle sweep..
M riser is 29cm, bottom of hinge plate for the upper part to the Bar clamp center ..
So what is the S riser stem measure out to?
fietsbob is offline  
Reply
Old 05-27-14 | 08:53 AM
  #16  
Newbie
 
Joined: May 2014
Posts: 2
Likes: 0
Hi fietsbob, (**** U ook nederlands spreken?)


I wondered if you figured out a way to use the "S type riser stem + aber hallo + MTB riser bar to get me back to M bar height"


I have a S2L-X, raw that I'm feeling a bit uncomfortable with. I believe increasing the bar height would help. Purchasing a completely new M stem and bars and cables is beyond my budget.


What has been your experience?


I'd be happy to move this to a general discussion if you wish.


Thanks,


Clark
anseldog is offline  
Reply
Old 05-27-14 | 09:51 AM
  #17  
Banned
 
Joined: Jun 2010
Posts: 43,586
Likes: 1,380
From: NW,Oregon Coast

Bikes: 8

Alstublieft, Just Visited several Times .. European cycle tours started from Shiphol.

The H riser , other than the hinge being higher off the headset .. turns out to be close to the Riser for The S bar ..

the riser for the M bar is is Lower than Both.. Build Your Brompton


there are Brompton Modifying shops ( one in NL, Brompton aanpassingen ),
to cut the head off the steering riser and add a QR telescoping inner post.

perhaps You have a Local Bike Frame builder willing to take on a similar job?

the Aberhallo and its Ilk is a 2 clamp pair which is a 1" tube that goes thru where the bar mounts
then the upper clamp pair holds the bar , aberhollow is offset many others are straight ..
https://www.bikeforums.net/folding-bi...-extender.html

the Center Bulge in many bars is not that wide , just wide enough to grip with the stem , then the rest is 7/8"

Last edited by fietsbob; 05-27-14 at 10:10 AM.
fietsbob is offline  
Reply
Old 05-25-20 | 04:05 AM
  #18  
Newbie
 
Joined: May 2020
Posts: 2
Likes: 0
Dear cyclocommuter, how was the change? Did everything work correctly? Did you cut the S-cables? What is your experience? Too low with the M-stem or ok? Thinking about switching as well. And can't change the stem, because I have the Explore special edition and the green colored stem exists only in M.
roitsch is offline  
Reply
Old 05-25-20 | 04:14 AM
  #19  
Senior Member
5 Anniversary
 
Joined: Feb 2017
Posts: 2,534
Likes: 568
This thread was started in 2011, the M stem and M handlebar have changed since then, the current M stem is higher and the current M handlebar is lower (the total height stem+handlebar is about the same).

Putting a S handlebar (or any flat handlebar) on the current M stem (as on the Explore) will result in a higher position than with the old M stem. Cables length reduction will be less than what it was with the old M stem.
Jipe is offline  
Reply
Old 05-25-20 | 04:18 AM
  #20  
Newbie
 
Joined: May 2020
Posts: 2
Likes: 0
Hi Jipe, Thanks for the quick answer. In order to have a sustainable switch, I will do like cyclocommuter planned: ordering some new S-cables for brakes and gears and keep the old ones for the M-Bar, in case if I ever want to switch back. Although the difference will be not that big anymore (like 2011), I still have to shorten the S-cables?
roitsch is offline  
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Barnstormer
Folding Bikes
8
12-22-15 04:18 AM
blakcloud
Folding Bikes
27
08-10-14 12:20 AM
Danni
Folding Bikes
16
01-22-12 05:44 PM
thatsut
Folding Bikes
27
07-16-10 08:58 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.