Weight Weenies
* FAQ    * Search    * Trending Topics
* Login   * Register
HOME Listings Blog NEW Galleries NEW FAQ Contact About Impressum
It is currently Fri Jan 19, 2018 3:00 am

All times are UTC+01:00





Post new topic  Reply to topic  [ 198 posts ]  Go to page Previous 14 5 6 7 814 Next
Author Message
PostPosted: Thu Dec 14, 2017 10:55 pm 
Offline

Joined: Thu Dec 14, 2017 10:51 pm
Posts: 1
spartan wrote:
https://knightcomposites.com/testing/

they have section on how the test rim failure. ironic part the youtube video is no longer available.

these clowns charge primo dollars for crap product. marketing. amazing cycling business

What:
Brakes are repeatedly applied and released to test the brake track durability and heat resistance.

How:
A rim is placed in the test rig and with a load of 100kg. It is then rotated constantly at 12.5kph, while the brakes are engaged and disengaged at a set pressure every 3 seconds. Rims should endure 3000 cycles of braking with no sign of failure to meet industry standards.

Why:
This tests how well the rim can withstand the heat generated from braking on the carbon track.

https://www.youtube.com/watch?v=T3Fu53u ... e=youtu.be
Video seems to be working fine now? What am I missing?

I have a pair of Knight Composites 35 Clinchers with almost 20K miles on them and lots of riding here in Southern Colorado and I've never had an issue with the wheels. I delaminated a pair of 303's descending on my local ride in 2014. I think any wheel company can have a bad day and soon enough, that day will come to Alto as well.


Top
   
Posted: Thu Dec 14, 2017 10:55 pm 


Top
   
 
PostPosted: Thu Dec 14, 2017 11:14 pm 
Offline
User avatar

Joined: Tue Apr 18, 2006 3:03 am
Posts: 2689
Location: Islip, NY
TobinHatesYou wrote:
There’s just as much friction in the 9lbs test with Alto’s rim vs the 7lbs test with the other rims.
I'd like this whole test to be independantly verified. There's no free lunch with material properties.

Sent from my SM-G950U using Tapatalk

_________________
www.ergottwheels.com


Top
   
PostPosted: Thu Dec 14, 2017 11:37 pm 
Offline

Joined: Mon Jul 24, 2017 12:02 pm
Posts: 556
ergott wrote:
TobinHatesYou wrote:
There’s just as much friction in the 9lbs test with Alto’s rim vs the 7lbs test with the other rims.
I'd like this whole test to be independantly verified. There's no free lunch with material properties.
That's true, but they aren't claiming magic. Basically the claim seems to be their choice of resin and layup technique allows the entire rim to function as a heatsink rather than a localized portion around the braketrack. I'd like to see the test reproduced by someone else too. It would be easy enough to do. The question is why would Ryan Mason (formerly Mason Cycle Werks) and Spark Wheel Works have any reason to lie?


Top
   
PostPosted: Thu Dec 14, 2017 11:39 pm 
Offline
in the industry

Joined: Wed Dec 30, 2009 12:31 pm
Posts: 52
TobinHatesYou wrote:

I'd like to see the test reproduced by someone else too. It would be easy enough to do.
https://www.youtube.com/watch?v=lARQCMfGWzc

_________________
http://www.boydcycling.com The Handcrafted Revolution


Top
   
PostPosted: Thu Dec 14, 2017 11:45 pm 
Offline

Joined: Mon Sep 25, 2017 1:36 pm
Posts: 33
coachboyd wrote:
TobinHatesYou wrote:

I'd like to see the test reproduced by someone else too. It would be easy enough to do.
https://www.youtube.com/watch?v=lARQCMfGWzc
Fire meet gasoline :D


Top
   
PostPosted: Thu Dec 14, 2017 11:59 pm 
Offline

Joined: Mon Jul 24, 2017 12:02 pm
Posts: 556
coachboyd wrote:
TobinHatesYou wrote:

I'd like to see the test reproduced by someone else too. It would be easy enough to do.
https://www.youtube.com/watch?v=lARQCMfGWzc
Hi Boyd, could you reveal what the equivalent power was for the test and the wheel speed under braking? I see the scale of the y-axis on the left of the screencap, but is it's km/h or mph? Looks like around "15" either way and the max temp was around 290F?


Top
   
PostPosted: Fri Dec 15, 2017 12:08 am 
Offline
User avatar

Joined: Tue Apr 18, 2006 3:03 am
Posts: 2689
Location: Islip, NY
TobinHatesYou wrote:

That's true, but they aren't claiming magic. Basically the claim seems to be their choice of resin and layup technique allows the entire rim to function as a heatsink rather than a localized portion around the braketrack. I'd like to see the test reproduced by someone else too. It would be easy enough to do. The question is why would Ryan Mason (formerly Mason Cycle Werks) and Spark Wheel Works have any reason to lie?
Carbon is generally an insulator hence the issue with it as a brake surface material.

I can't think of any instance of carbon fiber being used as a heat sink when aluminium is generally considered far better.

Resins have gotten better over time, but not that much. Unless this resin is something completely groundbreaking and will be highly sought after far outside the bike industry. Usually developments like this are driven by far bigger industries.

Sent from my SM-G950U using Tapatalk

_________________
www.ergottwheels.com


Top
   
PostPosted: Fri Dec 15, 2017 12:09 am 
Offline
in the industry

Joined: Wed Dec 30, 2009 12:31 pm
Posts: 52
The test was done as a constant 15kph and the brake load was set at 3.5kg

Braking force, temperature, speed, and rim width were monitored the entire time.
The blue line is the braking force needed. You can see it rises, and then as the brake pads heat up they start to shed material. Once that happens the braking force decreases and the temperature follows suit.

By the end of the test we could actually measure the brake pad residue on the rim (the green line).
If you watch the video you can see at the end of the test there is a ton of brake pad residue on the floor. We lost about 65% of the brake pad life in 20 minutes. The same brake pads will last for me for about 5 months or so on the front wheel and I am going up and down Paris Mountain in Greenville, SC on most of my rides.

Image

_________________
http://www.boydcycling.com The Handcrafted Revolution


Top
   
PostPosted: Fri Dec 15, 2017 12:20 am 
Offline

Joined: Mon Jul 24, 2017 12:02 pm
Posts: 556
So not quite the same protocol used. In Spark/Alto's test, each of the wheels were spinning closer to 31-32km/h.


Top
   
PostPosted: Fri Dec 15, 2017 12:40 am 
Online

Joined: Sat Oct 10, 2009 7:13 am
Posts: 1116
Location: 93306
ALTO WHEELS ARE THE BEST BECAUSE TOBIN BOUGHT SOME!!
(Just run them tubeless so you get extra credit)


Top
   
PostPosted: Fri Dec 15, 2017 12:47 am 
Offline

Joined: Mon Jul 24, 2017 12:02 pm
Posts: 556
tonytourist wrote:
ALTO WHEELS ARE THE BEST BECAUSE TOBIN BOUGHT SOME!!
(Just run them tubeless so you get extra credit)
I bought some and had a neutral experience with them. I even said I likely wouldn't buy them again. Your point?

And yes run them tubeless. Better yet, stop using rim brakes. These are all on my calling card.


Top
   
PostPosted: Fri Dec 15, 2017 12:54 am 
Offline
User avatar

Joined: Tue Apr 18, 2006 3:03 am
Posts: 2689
Location: Islip, NY
https://www.bikerumor.com/2017/12/14/en ... rake-test/

Sent from my SM-G950U using Tapatalk

_________________
www.ergottwheels.com


Top
   
PostPosted: Fri Dec 15, 2017 12:57 am 
Offline
User avatar

Joined: Tue Apr 18, 2006 3:03 am
Posts: 2689
Location: Islip, NY
Flrider wrote:
!

Image
Still waiting for clarification on this. How could these rims be of a proprietary mold made in the USA, sent to Taiwan and manage to be exactly the same as the Pacenti rim?


Also waiting for an answer to my question about brake surface texture. Things are just not adding up and that should concern anyone relying on this test result.



Sent from my SM-G950U using Tapatalk

_________________
www.ergottwheels.com


Top
   
PostPosted: Fri Dec 15, 2017 1:26 am 
Offline

Joined: Fri Sep 03, 2004 2:52 am
Posts: 1040
why even bother. your test is not realistic. constant speed should be closer to 35-40km/hr brake load set at 4-5kg.

if your confident send a pair of wheels to germany for testing by tour magazine. their alpine wheel test shreds majority of wheelsets they have tested :idea:
coachboyd wrote:
The test was done as a constant 15kph and the brake load was set at 3.5kg

Braking force, temperature, speed, and rim width were monitored the entire time.
The blue line is the braking force needed. You can see it rises, and then as the brake pads heat up they start to shed material. Once that happens the braking force decreases and the temperature follows suit.

By the end of the test we could actually measure the brake pad residue on the rim (the green line).
If you watch the video you can see at the end of the test there is a ton of brake pad residue on the floor. We lost about 65% of the brake pad life in 20 minutes. The same brake pads will last for me for about 5 months or so on the front wheel and I am going up and down Paris Mountain in Greenville, SC on most of my rides.

Image

_________________
Current Rides:

2017 Giant TCR Advanced SL 0 DI2 9150


Top
   
PostPosted: Fri Dec 15, 2017 1:31 am 
Offline
in the industry

Joined: Wed Dec 30, 2009 12:31 pm
Posts: 52
Most testing protocols are set between 12 and 16kph. It's not necessarily monitoring the speed, it's monitoring the braking force and temperature.

Kevin at Knight Composites has a lot of information about this and the ISO standards for testing. I need to look into the iso stuff more but I know those tests are run at 12.5 kph

_________________
http://www.boydcycling.com The Handcrafted Revolution


Top
   
Posted: Fri Dec 15, 2017 1:31 am 


Top
   
 
Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 198 posts ]  Go to page Previous 14 5 6 7 814 Next

   Similar Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. Bikeradar Tyre Test

[ Go to page: 1 2 ]

in Road

Ozrider

29

3830

Sun Mar 05, 2017 1:51 pm

kgt View the latest post

There are no new unread posts for this topic. Cycling Weekly Aero Bike Test 2. XR4 looking legit.

[ Go to page: 1 2 ]

in Road

Shrike

28

2672

Fri Dec 15, 2017 3:46 pm

F45 View the latest post

There are no new unread posts for this topic. Aero test. Trek Madone, Venge, Cervleo S5, Giant Propel & Canyon Aeroad

[ Go to page: 14 5 6 7 8 ]

in Road

User Name

105

15867

Wed Sep 20, 2017 5:38 pm

BeeSeeBee View the latest post

There are no new unread posts for this topic. Durable but high quality clincher

[ Go to page: 1 2 3 ]

in Road

Vagabond

38

3595

Sat Oct 28, 2017 12:08 pm

CBJ View the latest post

There are no new unread posts for this topic. Victoria corsa G+ un-gluing clincher

in Road

Allen254

10

939

Thu Nov 02, 2017 8:13 am

Marin View the latest post


All times are UTC+01:00


Who is online

Users browsing this forum: albertop07, Baidu [Spider], Google [Bot], Pschnei3, SimmyD and 33 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Limited