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

Rim Brakes on a BF NWT?

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.

Rim Brakes on a BF NWT?

Old 07-17-17, 08:21 AM
  #1  
slebo3213
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 183
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Rim Brakes on a BF NWT?

Anyone ever tried to fit standard rim brakes on a Bike Friday NWT? The frame looks to be drilled for brakes, although the reach on the rear seems like it might need some kind of extension.
slebo3213 is offline  
Old 07-17-17, 08:41 AM
  #2  
Rick Imby
Senior Member
 
Join Date: Sep 2015
Posts: 663
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 239 Post(s)
Likes: 0
Liked 1 Time in 1 Post
It comes with V-brakes I would guess which have much better leverage and stopping power. Caliper brakes when they end up with long arms from the frame to the rim do not work very well. Callipers work well with very tight clearance on 700c road bikes and really short arms and the tiny contact patch of the tire (very limited traction). They have never worked even reasonably well on BMX bikes which have much better traction and long distance between the rim and the mounting hole in the frame.
Rick Imby is offline  
Old 07-17-17, 09:25 AM
  #3  
BassNotBass
master of bottom licks
 
BassNotBass's Avatar
 
Join Date: Apr 2008
Location: Lou-evil, Canned-Yucky USA
Posts: 2,211
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Yeah, I would have to ask why anyone would want to fit calipers.
BassNotBass is offline  
Old 07-17-17, 10:21 AM
  #4  
slebo3213
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 183
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Thanks
slebo3213 is offline  
Old 07-24-17, 03:23 AM
  #5  
tudorowen1
Senior Member
 
Join Date: May 2006
Location: Cleethorpes..the last resort..UK
Posts: 331

Bikes: Brompton S6L ,Bike Friday NWT, Phillips 8 speed folder, Trek 930, Thorn XTC

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 68 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Perhaps you want to fit caliper brakes so you can fit drop bars on your NWT..I fitted mini V brakes to my NWT so I could use drop bars .But they will only work with tyres 20 x 1.50 inches..Any bigger and the cable will be touching the tyre..
tudorowen1 is offline  
Old 07-24-17, 04:52 AM
  #6  
amyanderson
Banned.
 
Join Date: Jul 2017
Posts: 9
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
I have a question why people use fit caplisers I think there is no need of this it just a burden on bike
amyanderson is offline  
Old 07-24-17, 10:37 AM
  #7  
dabac
Senior Member
 
Join Date: Mar 2008
Posts: 8,453
Mentioned: 45 Post(s)
Tagged: 0 Thread(s)
Quoted: 1000 Post(s)
Liked 196 Times in 147 Posts
Originally Posted by Rick Imby View Post
....tiny contact patch of the tire (very limited traction). They have never worked even reasonably well on BMX bikes which have much better traction...
Huh?

On a soft/loose surface, sure.

But I've never experienced, or heard about 700 C road bikes having poor traction on firm, grippy surfaces.
dabac is offline  
Old 07-24-17, 03:03 PM
  #8  
Rick Imby
Senior Member
 
Join Date: Sep 2015
Posts: 663
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 239 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by dabac View Post
Huh?

On a soft/loose surface, sure.

But I've never experienced, or heard about 700 C road bikes having poor traction on firm, grippy surfaces.
700x25c have some grip on pavement but not nearly what you get from a wide low pressure---30-40 psi tire. The contact patch is directly related to PSI. Higher psi equals smaller contact patch. with 110 psi the contact patch is so small any irregularity, sand, grease, water will allow the tire to slip.

If you have not experienced a 700x25 tire slide on pavement you are lucky. Firm grippy surfaces need very little irregularity to cause a high pressure tire to lose traction at fairly high speed.
Rick Imby is offline  
Old 07-24-17, 04:32 PM
  #9  
badmother
Senior Member
 
badmother's Avatar
 
Join Date: Nov 2007
Posts: 3,720
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 317 Post(s)
Likes: 0
Liked 1 Time in 1 Post
I got some new cheap cantis for my 90`s Scott MTB. Tectro I think. Great brakes, regular brakepads easy to adjust. They are w i d e so maybe not the best if you fold and pack the bikes often but plenty clerance for fat tyres. Same as drum brakes, they are not rubish just becouse they are not "new".

And since brakes is discussed: Did anybody try out these:

or something like this: https://www.ebay.com/itm/V-brake-exte...c8fHcuKAIS-sSA

bumped into them by accident. several sellers and similar products for the second one. Found only one for the first one.

Last edited by badmother; 07-25-17 at 04:52 AM.
badmother is offline  
Old 07-25-17, 05:18 AM
  #10  
dabac
Senior Member
 
Join Date: Mar 2008
Posts: 8,453
Mentioned: 45 Post(s)
Tagged: 0 Thread(s)
Quoted: 1000 Post(s)
Liked 196 Times in 147 Posts
Originally Posted by Rick Imby View Post
700x25c have some grip on pavement but not nearly what you get from a wide low pressure---30-40 psi tire. The contact patch is directly related to PSI. Higher psi equals smaller contact patch.
But available friction is higly dependent on pressure between tire and road. The smaller the contact patch, the higher the pressure between tire and road becomes.

A wider tire has a bigger contact patch, but lower tire/road pressure. On a firm road surface (and regular friction mechanics) - no net gain.

Originally Posted by Rick Imby View Post
... any irregularity, sand, grease, water will allow the tire to slip.
Then it's not what I consider as a "firm surface", and outside the scope of my original statement.

Originally Posted by Rick Imby View Post
If you have not experienced a 700x25 tire slide on pavement you are lucky.
Clean and dry pavement - no. Not unless I intentionally lock the rear wheel up.
On sandy patches, manhole covers, lane markers, wet leaves etc - sure.
dabac is offline  
Old 07-26-17, 05:45 PM
  #11  
Rick Imby
Senior Member
 
Join Date: Sep 2015
Posts: 663
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 239 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by dabac View Post
But available friction is higly dependent on pressure between tire and road. The smaller the contact patch, the higher the pressure between tire and road becomes.

A wider tire has a bigger contact patch, but lower tire/road pressure. On a firm road surface (and regular friction mechanics) - no net gain.



Then it's not what I consider as a "firm surface", and outside the scope of my original statement.


Clean and dry pavement - no. Not unless I intentionally lock the rear wheel up.
On sandy patches, manhole covers, lane markers, wet leaves etc - sure.
So I guess you are saying that a skinny tired bike with caliper brakes on clean dry pavement can stop in as short a distance as a fat tire bike with large contact patch disc brakes?

I am certain the more forward position of high end road bikes makes me feel more susceptible to launching over the front. But with the same riding positions you are saying small contact patch will create the same friction.

I don't know the answers to the traction equation---

I have always thought wider tires with lower tire pressure (and larger footprints) could stop faster. I have no physics to back this up----only feelings from my riding no data or physical equations to back up the feeling.

The other factor I have rarely seen is clean dry pavement throughout my ride.---Hence my fondness for fatter tires----grin

What I have tried to say is I have no knowledge of the physics behind friction mechanics...

Last edited by Rick Imby; 07-26-17 at 05:52 PM.
Rick Imby is offline  
Old 07-27-17, 12:54 AM
  #12  
dabac
Senior Member
 
Join Date: Mar 2008
Posts: 8,453
Mentioned: 45 Post(s)
Tagged: 0 Thread(s)
Quoted: 1000 Post(s)
Liked 196 Times in 147 Posts
Originally Posted by Rick Imby View Post
So I guess you are saying that a skinny tired bike with caliper brakes on clean dry pavement can stop in as short a distance as a fat tire bike with large contact patch disc brakes?
Overall stopping distance depends on a chain of things. It's friction between tire and ground, brake power, brake modulation, rider CoG, wheel base, rider skill...
But yeah, on clean, firm pavement, the bigger contact patch is not a guaranteed advantage.
Originally Posted by Rick Imby View Post
I am certain the more forward position of high end road bikes makes me feel more susceptible to launching over the front....
I can't argue with what you feel. That's a personal experience.

Whether your concern is valid or not, I can't tell straight off.
You'd have to compare rider CoG WRT contact patch position.

I think that a properly positioned (off the saddle, body back and low) road bike rider would have less risk of OTB than a casually positioned Fat Bike rider.

Originally Posted by Rick Imby View Post
But with the same riding positions you are saying small contact patch will create the same friction.
Pretty much. If all other things remain the same, the pressure is proportional to the area. 1/3 of the area gives 3x the pressure. And that pressure over the contact patch is the main driver of how much available friction there is.

Originally Posted by Rick Imby View Post
I don't know the answers to the traction equation---...I have no knowledge of the physics behind friction mechanics...
Friction quickly becomes complicated. There's static friction, sliding friction...
Then you add a tire that deforms and squirms. After awhile you get into the sticky, high-performance car and motorcycle tires.
But for bicycles, fairly basic assumptions will get you there.

Originally Posted by Rick Imby View Post
I have always thought wider tires with lower tire pressure (and larger footprints) could stop faster....
There is a saying:"logic is a way of going wrong with confidence".

But really, if the wider tire is ALSO knobbly, it doesn't take much to notice that you're losing out.
Particularly high/tall knobs quickly starts to wiggle and squirm when cornering or braking, reducing your control of the bike.

Originally Posted by Rick Imby View Post
The other factor I have rarely seen is clean dry pavement throughout my ride.---Hence my fondness for fatter tires----grin
Plenty of reasons to avoid the skinniest tires, even if riding on good roads.
Just ar there are good reasons to avoid wide, knobbly tires on roads.
dabac is offline  
Old 07-31-17, 03:13 AM
  #13  
dabac
Senior Member
 
Join Date: Mar 2008
Posts: 8,453
Mentioned: 45 Post(s)
Tagged: 0 Thread(s)
Quoted: 1000 Post(s)
Liked 196 Times in 147 Posts
Originally Posted by badmother View Post

And since brakes is discussed: Did anybody try out these:DIY Bicycle Bike Brake Modified Refit holder Support Base V Brake to Disc Brake | eBay
I've considered buying those. Not to use as-is, but to use as prefab mounts to weld to frames and forks. Save me some hacksawing and filing.

I rather doubt their overall usefulness. Disc brake calipers don't have much sideways adjustability. And that design has the caliper's position dependent on dropout thickness.
And I suspect that can vary enough to cause trouble for the design.
Originally Posted by badmother View Post
No.
That design too has me wondering. Moving the brake boss like that, there'll be a decent amount of force pushing the adapters apart. What's keeping the adapters aligned?
dabac is offline  
Old 07-31-17, 06:20 AM
  #14  
jur
Senior Member
 
Join Date: May 2005
Location: Melbourne
Posts: 7,391
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 318 Post(s)
Likes: 0
Liked 3 Times in 2 Posts
^ the pin on the back.
jur is offline  
Old 07-31-17, 06:59 AM
  #15  
smallwheeler
Senior Member
 
smallwheeler's Avatar
 
Join Date: Aug 2012
Location: NYC
Posts: 2,379
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 150 Post(s)
Likes: 0
Liked 6 Times in 6 Posts
^ lol
smallwheeler is offline  
Old 07-31-17, 08:34 AM
  #16  
fietsbob
Banned
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 43,599

Bikes: 8

Mentioned: 197 Post(s)
Tagged: 0 Thread(s)
Quoted: 7607 Post(s)
Liked 1,309 Times in 822 Posts
Originally Posted by slebo3213 View Post
Anyone ever tried to fit standard rim brakes on a Bike Friday NWT? The frame looks to be drilled for brakes, although the reach on the rear seems like it might need some kind of extension.
they use V brakes, if not using disc brakes, maybe if you use a 451 rim wheel set,

In a 406 wheel frame and fork, then you may be able to use a side pull caliper.. good luck..


my 2 Bike Fridays are V and Disc Brake.





....
fietsbob is offline  
Old 07-31-17, 08:41 AM
  #17  
badmother
Senior Member
 
badmother's Avatar
 
Join Date: Nov 2007
Posts: 3,720
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 317 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by dabac View Post
I've considered buying those. Not to use as-is, but to use as prefab mounts to weld to frames and forks. Save me some hacksawing and filing.

I rather doubt their overall usefulness. Disc brake calipers don't have much sideways adjustability. And that design has the caliper's position dependent on dropout thickness.
And I suspect that can vary enough to cause trouble for the design.


No.
That design too has me wondering. Moving the brake boss like that, there'll be a decent amount of force pushing the adapters apart. What's keeping the adapters aligned?
Sounds like a good idea to use the disk mounts for weld on projects. Would have been nice if there was an easy solution for frames that need a good brake solution but I am not sure this is the solution. Adjustment is one thing but I`d like to know if they stay in position under heavy braking or if they twist

The other ones: What keeps them in position may be that small thingy sticking out at the back in picture four pluss I would guess they are made so that tightening the screw that conects them to the frame would keep them in place instead of letting them rotate like a V brake would do.
badmother is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
ljsense
Road Cycling
241
03-04-19 08:40 AM
DaveDaBrave
Bicycle Mechanics
5
12-11-16 09:13 AM
Fastfwd01
Road Cycling
5
10-02-15 03:35 PM
spdracr39
General Cycling Discussion
1
08-25-15 08:29 AM
acidfast7
Commuting
10
01-19-13 05:25 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


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.