A Cycling & bikes forum. CycleBanter.com

Go Back   Home » CycleBanter.com forum » rec.bicycles » Techniques
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Disc brakes, adaptors to increase rotor diameter



 
 
Thread Tools Display Modes
  #11  
Old October 12th 17, 04:20 PM posted to rec.bicycles.tech
Andre Jute[_2_]
external usenet poster
 
Posts: 8,523
Default Disc brakes, adaptors to increase rotor diameter

On Thursday, October 12, 2017 at 4:04:07 AM UTC+1, Tim McNamara wrote:
On Wed, 11 Oct 2017 18:16:20 -0700 (PDT), jbeattie
wrote:
On Wednesday, October 11, 2017 at 2:36:03 PM UTC-7, Joerg wrote:
The adapters to increase rotor size in a post-post situation (which I
have front and back) look like this:


If you keep following that logic, you'll have a disc diameter of 622 mm.

Oh, wait....


I already have a brake disc diameter of 622mm. You could too. First, buy a bike with standard 622mm rims. Next, fit Magura hydraulic rim brakes (several varieties available for touring, utility and road bikes). Result, powerful but very manageable 622mm disc brakes, economical on "pads" too. Hey presto, your brakes are powerful enough to ride with Joerg.

Andre Jute
Logic is good, but common sense is essential
Ads
  #12  
Old October 12th 17, 05:26 PM posted to rec.bicycles.tech
JBeattie
external usenet poster
 
Posts: 2,821
Default Disc brakes, adaptors to increase rotor diameter

On Thursday, October 12, 2017 at 7:36:15 AM UTC-7, Joerg wrote:
On 2017-10-11 18:16, jbeattie wrote:
On Wednesday, October 11, 2017 at 2:36:03 PM UTC-7, Joerg wrote:
The adapters to increase rotor size in a post-post situation (which
I have front and back) look like this:

http://i.ebayimg.com/images/g/oK8AAO...Au/s-l1600.jpg

My MTB has a factory one from 160 to 180mm up front but I am
considering 203mm. That would make the thing even more extreme,
like this where the screws would look more cattywompus or out of
line than they already do:

https://i.ebayimg.com/images/g/w4MAA...bTa/s-l500.jpg

Why are the spacings so different on both sides while for 160mm
their are not?


The angle of the caliper changes as you get into the larger rotor
sizes and thus the disparity.



Understood. This is also what Ralph wrote. However, many calipers such
as mine have round pads where it doesn't matter if the angle is slighlty
different.


I don't know your brakes, but the rotor might hit the internals if the caliper is not angled correctly. You want the mechanism following the arc of the rotor, which is what you will get with your spacer. You also want to engage as much of the rotor as possible. I don't think any of this is optional, is it? You just put in the spacer, and you're done.

-- Jay Beattie.
  #13  
Old October 13th 17, 04:16 PM posted to rec.bicycles.tech
Joerg[_2_]
external usenet poster
 
Posts: 4,701
Default Disc brakes, adaptors to increase rotor diameter

On 2017-10-12 09:26, jbeattie wrote:
On Thursday, October 12, 2017 at 7:36:15 AM UTC-7, Joerg wrote:
On 2017-10-11 18:16, jbeattie wrote:
On Wednesday, October 11, 2017 at 2:36:03 PM UTC-7, Joerg wrote:
The adapters to increase rotor size in a post-post situation
(which I have front and back) look like this:

http://i.ebayimg.com/images/g/oK8AAO...Au/s-l1600.jpg

My MTB has a factory one from 160 to 180mm up front but I am
considering 203mm. That would make the thing even more
extreme, like this where the screws would look more cattywompus
or out of line than they already do:

https://i.ebayimg.com/images/g/w4MAA...bTa/s-l500.jpg

Why are the spacings so different on both sides while for
160mm their are not?

The angle of the caliper changes as you get into the larger
rotor sizes and thus the disparity.



Understood. This is also what Ralph wrote. However, many calipers
such as mine have round pads where it doesn't matter if the angle
is slighlty different.


I don't know your brakes, but the rotor might hit the internals if
the caliper is not angled correctly. You want the mechanism following
the arc of the rotor, which is what you will get with your spacer.



It should also work with this spacer which avoids long screws:

https://erpimgs.idealhere.com/ImageF...963c864243.jpg

It moves the rotor out plus up so the angle should remain roughly
similar. Shimano has these as well but I just got an answer from Jenson
USA which carries them. They are flat and only 10mm (looks less though)
and my calipers need more "dive room" than that.

http://www.jensonusa.com/Shimano-F20...Z47&l=BR407Z47

So I'd need the bellied ones like in the link.


You also want to engage as much of the rotor as possible. I don't
think any of this is optional, is it? You just put in the spacer, and
you're done.


Just have to make sure it's the correct adapter. Adding a washer here or
there for fine tuning isn't a problem.

--
Regards, Joerg

http://www.analogconsultants.com/
  #14  
Old October 13th 17, 04:50 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 3,346
Default Disc brakes, adaptors to increase rotor diameter

On Friday, October 13, 2017 at 8:15:57 AM UTC-7, Joerg wrote:
On 2017-10-12 09:26, jbeattie wrote:
On Thursday, October 12, 2017 at 7:36:15 AM UTC-7, Joerg wrote:
On 2017-10-11 18:16, jbeattie wrote:
On Wednesday, October 11, 2017 at 2:36:03 PM UTC-7, Joerg wrote:
The adapters to increase rotor size in a post-post situation
(which I have front and back) look like this:

http://i.ebayimg.com/images/g/oK8AAO...Au/s-l1600.jpg

My MTB has a factory one from 160 to 180mm up front but I am
considering 203mm. That would make the thing even more
extreme, like this where the screws would look more cattywompus
or out of line than they already do:

https://i.ebayimg.com/images/g/w4MAA...bTa/s-l500.jpg

Why are the spacings so different on both sides while for
160mm their are not?

The angle of the caliper changes as you get into the larger
rotor sizes and thus the disparity.


Understood. This is also what Ralph wrote. However, many calipers
such as mine have round pads where it doesn't matter if the angle
is slighlty different.


I don't know your brakes, but the rotor might hit the internals if
the caliper is not angled correctly. You want the mechanism following
the arc of the rotor, which is what you will get with your spacer.



It should also work with this spacer which avoids long screws:

https://erpimgs.idealhere.com/ImageF...963c864243.jpg

It moves the rotor out plus up so the angle should remain roughly
similar. Shimano has these as well but I just got an answer from Jenson
USA which carries them. They are flat and only 10mm (looks less though)
and my calipers need more "dive room" than that.

http://www.jensonusa.com/Shimano-F20...Z47&l=BR407Z47

So I'd need the bellied ones like in the link.


You also want to engage as much of the rotor as possible. I don't
think any of this is optional, is it? You just put in the spacer, and
you're done.


Just have to make sure it's the correct adapter. Adding a washer here or
there for fine tuning isn't a problem.


I'm still having this problem with why you would want disk brakes on a road bike in California. Extra weight, extra rolling resistance, extra cost, far too much power the way it was and there is little rain in California to worry about the slight delay in action between a rim and disk brake.
  #15  
Old October 13th 17, 06:15 PM posted to rec.bicycles.tech
Joerg[_2_]
external usenet poster
 
Posts: 4,701
Default Disc brakes, adaptors to increase rotor diameter

On 2017-10-13 08:50, wrote:
On Friday, October 13, 2017 at 8:15:57 AM UTC-7, Joerg wrote:
On 2017-10-12 09:26, jbeattie wrote:
On Thursday, October 12, 2017 at 7:36:15 AM UTC-7, Joerg wrote:
On 2017-10-11 18:16, jbeattie wrote:
On Wednesday, October 11, 2017 at 2:36:03 PM UTC-7, Joerg
wrote:
The adapters to increase rotor size in a post-post
situation (which I have front and back) look like this:

http://i.ebayimg.com/images/g/oK8AAO...Au/s-l1600.jpg

My MTB has a factory one from 160 to 180mm up front but I
am considering 203mm. That would make the thing even more
extreme, like this where the screws would look more
cattywompus or out of line than they already do:

https://i.ebayimg.com/images/g/w4MAA...bTa/s-l500.jpg

Why are the spacings so different on both sides while for
160mm their are not?

The angle of the caliper changes as you get into the larger
rotor sizes and thus the disparity.


Understood. This is also what Ralph wrote. However, many
calipers such as mine have round pads where it doesn't matter
if the angle is slighlty different.

I don't know your brakes, but the rotor might hit the internals
if the caliper is not angled correctly. You want the mechanism
following the arc of the rotor, which is what you will get with
your spacer.



It should also work with this spacer which avoids long screws:

https://erpimgs.idealhere.com/ImageF...963c864243.jpg



It moves the rotor out plus up so the angle should remain roughly
similar. Shimano has these as well but I just got an answer from
Jenson USA which carries them. They are flat and only 10mm (looks
less though) and my calipers need more "dive room" than that.

http://www.jensonusa.com/Shimano-F20...Z47&l=BR407Z47



So I'd need the bellied ones like in the link.


You also want to engage as much of the rotor as possible. I
don't think any of this is optional, is it? You just put in the
spacer, and you're done.


Just have to make sure it's the correct adapter. Adding a washer
here or there for fine tuning isn't a problem.


I'm still having this problem with why you would want disk brakes on
a road bike in California.



It is for my mountain bike. Currently it has 7" up front and 6" in back.
That is only borderline adequate for the loading and riding I do.
Yesterday I rode a trail where I taxed them a bit much again. I want to
upgrade both wheels to 8". Both are native 160mm and the front has an
adapter which I'd have to change out.

There is nothing that can replace brake power. Except more brake power.


... Extra weight, extra rolling resistance,
extra cost, far too much power the way it was and there is little
rain in California to worry about the slight delay in action between
a rim and disk brake.


In the winter it rains a lot up here in the Sierra foothills. There is
also a lot of standing water and creek crossings after which I
experience that dreaded 1-2sec "free fall" with rim brakes. Plus dirt
where I reach in and while getting some tepid brake response there is a
goose bump generating sandpaper noise.

So yes, if I ever need a new road bike I have two non-negotiable
requirements. Number one is disk brakes and number two is that the frame
must accept cyclocross-width tires. And must tolerate a serious rack.

--
Regards, Joerg

http://www.analogconsultants.com/
  #16  
Old October 13th 17, 07:36 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 3,346
Default Disc brakes, adaptors to increase rotor diameter

On Friday, October 13, 2017 at 10:15:10 AM UTC-7, Joerg wrote:
On 2017-10-13 08:50, wrote:
On Friday, October 13, 2017 at 8:15:57 AM UTC-7, Joerg wrote:
On 2017-10-12 09:26, jbeattie wrote:
On Thursday, October 12, 2017 at 7:36:15 AM UTC-7, Joerg wrote:
On 2017-10-11 18:16, jbeattie wrote:
On Wednesday, October 11, 2017 at 2:36:03 PM UTC-7, Joerg
wrote:
The adapters to increase rotor size in a post-post
situation (which I have front and back) look like this:

http://i.ebayimg.com/images/g/oK8AAO...Au/s-l1600.jpg

My MTB has a factory one from 160 to 180mm up front but I
am considering 203mm. That would make the thing even more
extreme, like this where the screws would look more
cattywompus or out of line than they already do:

https://i.ebayimg.com/images/g/w4MAA...bTa/s-l500.jpg

Why are the spacings so different on both sides while for
160mm their are not?

The angle of the caliper changes as you get into the larger
rotor sizes and thus the disparity.


Understood. This is also what Ralph wrote. However, many
calipers such as mine have round pads where it doesn't matter
if the angle is slighlty different.

I don't know your brakes, but the rotor might hit the internals
if the caliper is not angled correctly. You want the mechanism
following the arc of the rotor, which is what you will get with
your spacer.


It should also work with this spacer which avoids long screws:

https://erpimgs.idealhere.com/ImageF...963c864243.jpg



It moves the rotor out plus up so the angle should remain roughly
similar. Shimano has these as well but I just got an answer from
Jenson USA which carries them. They are flat and only 10mm (looks
less though) and my calipers need more "dive room" than that.

http://www.jensonusa.com/Shimano-F20...Z47&l=BR407Z47



So I'd need the bellied ones like in the link.


You also want to engage as much of the rotor as possible. I
don't think any of this is optional, is it? You just put in the
spacer, and you're done.


Just have to make sure it's the correct adapter. Adding a washer
here or there for fine tuning isn't a problem.


I'm still having this problem with why you would want disk brakes on
a road bike in California.



It is for my mountain bike. Currently it has 7" up front and 6" in back.
That is only borderline adequate for the loading and riding I do.
Yesterday I rode a trail where I taxed them a bit much again. I want to
upgrade both wheels to 8". Both are native 160mm and the front has an
adapter which I'd have to change out.

There is nothing that can replace brake power. Except more brake power.


... Extra weight, extra rolling resistance,
extra cost, far too much power the way it was and there is little
rain in California to worry about the slight delay in action between
a rim and disk brake.


In the winter it rains a lot up here in the Sierra foothills. There is
also a lot of standing water and creek crossings after which I
experience that dreaded 1-2sec "free fall" with rim brakes. Plus dirt
where I reach in and while getting some tepid brake response there is a
goose bump generating sandpaper noise.

So yes, if I ever need a new road bike I have two non-negotiable
requirements. Number one is disk brakes and number two is that the frame
must accept cyclocross-width tires. And must tolerate a serious rack.


Perhaps going balls-to-the-walls on an MTB with a heavy load you can detect a braking delay but as I said before - even coming out of creek crossings I never have problems with rim brakes. The ONLY difference is surface area of the brake shoes.
  #17  
Old October 14th 17, 03:13 PM posted to rec.bicycles.tech
Joerg[_2_]
external usenet poster
 
Posts: 4,701
Default Disc brakes, adaptors to increase rotor diameter

On 2017-10-13 11:36, wrote:
On Friday, October 13, 2017 at 10:15:10 AM UTC-7, Joerg wrote:
On 2017-10-13 08:50,
wrote:

[...]


... Extra weight, extra rolling resistance, extra cost, far too
much power the way it was and there is little rain in California
to worry about the slight delay in action between a rim and disk
brake.


In the winter it rains a lot up here in the Sierra foothills. There
is also a lot of standing water and creek crossings after which I
experience that dreaded 1-2sec "free fall" with rim brakes. Plus
dirt where I reach in and while getting some tepid brake response
there is a goose bump generating sandpaper noise.

So yes, if I ever need a new road bike I have two non-negotiable
requirements. Number one is disk brakes and number two is that the
frame must accept cyclocross-width tires. And must tolerate a
serious rack.


Perhaps going balls-to-the-walls on an MTB with a heavy load you can
detect a braking delay but as I said before - even coming out of
creek crossings I never have problems with rim brakes. The ONLY
difference is surface area of the brake shoes.


Getting older I don't ride aggressivley anymore. Maybe because the more
I ride the more I see and hear about nasty crashes and their aftermath.

Creek crossings usually mean uphill at the other end but they also mean
the rims can be muddy. My Wednesday ride was on a very typical
singletrack of that kind. Up and down all the time and with a creek at
the bottoms. On my old rim brake MTB that would have meant going down
the slopes after the uphill section with sandpapering brakes. There are
no bike wash stations on the trails. It's a horrid sound because our
soil contains a lot of decomposed granite. After about 1000mi the rims
of that old MTB look pretty much shot.

The white knuckle moment with the rim brakes on my old MTB happened
while up on the flat section of a hill. Curvy trail along the rim. Went
through a large puddle, towards a sharp turn, hit the brakes, no brakes!

Pad size doesn't matter much except that wider pads last longer. So if
my brake calipers are through I'll look for ones that have wider pads or
maybe even double pads. The pads will cost more but then I hopefully
don't have to replace them every 800-1000mi.

--
Regards, Joerg

http://www.analogconsultants.com/
 




Thread Tools
Display Modes

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

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Shimming up caliper to increase rotor size on MTB brakes Joerg[_2_] Techniques 3 July 22nd 17 01:17 AM
Disc Rotor Refurb? (PeteCresswell) Techniques 14 January 20th 10 02:40 AM
adaptors for mtb disc brakes Mikeatlbch Off Road 1 April 18th 04 05:10 PM
Disc brake adaptors joemarshall Unicycling 21 January 22nd 04 10:48 PM
disc brake adaptors/relacement stanctions Pottsy Mountain Biking 1 September 21st 03 06:45 PM


All times are GMT +1. The time now is 07:44 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright 2004-2017 CycleBanter.com.
The comments are property of their posters.