Retrobike Forum Index

It is currently Sat Dec 03, 2016 12:51 pm

* Login   * Register * Search  * FAQ



Post new topic Reply to topic  [ 13 posts ]  Go to page 1, 2  Next
Author Message
PostPosted: Sat Jan 03, 2009 12:33 pm 
Retro Guru
User avatar

Joined: Mon Jan 07, 2008 3:59 pm
Posts: 1093
Location: Nottingham JustGoRide.co.uk
Believe it or not, applied my front brake in a car park prior to a ride and BOSH.. :shock: Glad I didn't actually need to stop.


Attachments:
BustHope.jpg
BustHope.jpg [ 55.26 KiB | Viewed 1199 times ]
SomeHope.jpg
SomeHope.jpg [ 57.97 KiB | Viewed 1199 times ]
Top
 Profile  
 
 Post subject:
PostPosted: Sat Jan 03, 2009 1:03 pm 
retrobike rider
retrobike rider
User avatar

Joined: Sun Dec 02, 2007 6:35 pm
Posts: 5802
Location: Dunkeswell, Nr Honiton, Devon
at least its hope, they should be good for spare parts


Top
 Profile  
 
 Post subject:
PostPosted: Sat Jan 03, 2009 1:06 pm 
Retro Guru
User avatar

Joined: Mon Jan 07, 2008 3:59 pm
Posts: 1093
Location: Nottingham JustGoRide.co.uk
Very true, thats the replacement master cylinder lever body in the second picture. Just building it up now. I'm going to send the broken one back to Hope.. It really is machined to within an inch of its life and really should not have broken that easily.. its only 18 months old!

Just got to refit the hose and bleed the bugger now! :?


Attachments:
NewHope.jpg
NewHope.jpg [ 60.06 KiB | Viewed 1179 times ]
Top
 Profile  
 
 Post subject:
PostPosted: Sat Jan 03, 2009 6:56 pm 
Retro Guru
User avatar

Joined: Wed Feb 14, 2007 12:49 am
Posts: 807
Location: hiding under the bed
out of interest, do you have carbon monkey bars, easton ones?


Top
 Profile  
 
 Post subject:
PostPosted: Sat Jan 03, 2009 7:50 pm 
Dirt Disciple

Joined: Mon Nov 10, 2008 2:14 am
Posts: 87
Dude! You post this now? I just finished ordering a set of Hope Mini X2 Pro Disc Brakes!


Top
 Profile  
 
 Post subject:
PostPosted: Sat Jan 03, 2009 8:41 pm 
98+ BoTM Winner / Gold Trader
98+ BoTM Winner / Gold Trader
User avatar

Joined: Wed Aug 15, 2007 7:29 pm
Posts: 1650
Location: Netherlands
Can you post close ups of the surfaces surrounding the cracks please? I'd like to understand this (I also have a set).

The cracked surface itself will also hold clues.


Top
 Profile  
 
 Post subject:
PostPosted: Sat Jan 03, 2009 9:15 pm 
Moderator /Lincs, E & S Yorks Deputy AEC
Moderator /Lincs, E & S Yorks Deputy AEC
User avatar

Joined: Mon Nov 26, 2007 6:16 pm
Posts: 4144
Location: RetroModding™ since 1988
I have a set of these too, so far so good....

Would be nice to know what may have caused the failure though.


Top
 Profile  
 
 Post subject:
PostPosted: Sat Jan 03, 2009 11:55 pm 
Retro Guru
User avatar

Joined: Mon Jan 07, 2008 3:59 pm
Posts: 1093
Location: Nottingham JustGoRide.co.uk
Hmm, I do have carbon Easton MonkeyLite XC Low CNT bars... whys that then...???? :|

Don't worry about X2's.. the new lever is far more chunky.

I'm not sure what caused it, you can see some slight scuffing on the res cap which happened after a very small crash about 6 months ago, still I wouldn't have though that this would cause it to fail this long afterwards. and the crash hardly effected the lever. It was bloody cold when it happened, and the bike had just come off a bike rack after an hours drive?

I'll sort out some close up pic's..


Last edited by OrangeRetro on Sun Jan 04, 2009 12:13 am, edited 1 time in total.

Top
 Profile  
 
 Post subject:
PostPosted: Sun Jan 04, 2009 12:10 am 
Retro Guru
User avatar

Joined: Mon Jan 07, 2008 3:59 pm
Posts: 1093
Location: Nottingham JustGoRide.co.uk
Here's the close ups..

It's going back to Hope to be checked out so i'll post an update.. I doubt they'll replace it but it would be nice to find out what happened!

As luck would have it I got the replacement master cyclinder for £12 from the CRC flood sale! It's all back together and working again.. I just hope that it's a one off!


Attachments:
SmallBreak.jpg
SmallBreak.jpg [ 28.38 KiB | Viewed 1069 times ]
LargeBreak.jpg
LargeBreak.jpg [ 46.58 KiB | Viewed 1069 times ]
Top
 Profile  
 
 Post subject:
PostPosted: Sun Jan 04, 2009 1:54 am 
98+ BoTM Winner / Gold Trader
98+ BoTM Winner / Gold Trader
User avatar

Joined: Wed Aug 15, 2007 7:29 pm
Posts: 1650
Location: Netherlands
Tough to say form the pictures, but here goes with some typical aspects:

It being very cold will not have helped. If it was just freezing and you had some speed the extra cooling due to wind chill takes it to -23 degC or so. see this link: http://www.eol.ucar.edu/homes/rilling/wc_table.html Not sure if that is enough to cause trouble though, need to know more about the alloy and it's treatment. But I doubt the cold alone could cause a complete brittle failure.

Also because I see some rough surface with shadows as if there are "peaks" in the far left in the second picture. This could be gross deformations from over stressing. Such deformations are commonly seen on fractures that have cracked over a large percentage of the surface area when the last bit is just torn apart. The first picture is more difficult to judge, but there appears to be a colour difference with the far right of it being a lighter shade (this would be corresponding to the "peaks"area in the other picture?)

Now if the larger remaning area of the fracture is indeed not just darker but also smoother, dull in appearance or even with water/dirt or corrosion products on it that would make sense. It would indicate that it started with a small crack some time ago which grew over time, until it was so far the remaining ligament gave up under your braking action, the cold not helping at that fatal event.

The critical elements to observe being that the long time frame of the growing crack meant water/dirt and corrosion had access to the already cracked surface, and that the original crack had to strat somewhere. Otherwise this to me would be a plausible scenario, though it takes a lot of extrapolating from hints in the two pictures.

Do you see any of the features supporting this scenario clearly, or not at all?


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 13 posts ]  Go to page 1, 2  Next

All times are UTC [ DST ]


Who is online

Users browsing this forum: unkleGsif and 20 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:  

About Us

Follow Retrobike

Other cool stuff

All content © 2005-2015 Retrobike unless otherwise stated.
Cookies Policy.
bikedeals - the best bike deals in one place
FatCOGS - Fat Chance Owner's Group

Powered by phpBB® Forum Software © phpBB Group