Strange wear caliper bolts - BMW Luxury Touring Community
 4Likes
  • 1 Post By sailor
  • 1 Post By 11862
  • 2 Post By dshealey
 
LinkBack Thread Tools Display Modes
post #1 of 17 Old Jan 19th, 2015, 2:33 am Thread Starter
Member
 
Join Date: Jul 2012
Location: Voorst, , The Netherlands
Posts: 38
Strange wear caliper bolts

When mounting the brake caliper on the front right side, I tried to turn the bolts to the proper torque (40nm). However, I soon felt that I had no grip and then one broke off.

See the picture. What you can see is that part of the bolt is thinner than the rest. Does anyone know what can have caused this? Does anyone have experience with this?

I already bought 4 new bolts. The caliper on the left side showed the same strange wear.



Greetings from the Netherlands.
tonvanunen is offline  
Sponsored Links
Advertisement
 
post #2 of 17 Old Jan 19th, 2015, 4:29 am
Enjoy The Ride
 
saddleman's Avatar
 
Join Date: Sep 2008
Location: Huntersville, NC, USA
Posts: 3,888
Re: Strange wear caliper bolts

They have been over torqued at one time or another.

Dave Selvig
2004 Black LT
2000 Canon Red LT



To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
saddleman is online now  
post #3 of 17 Old Jan 19th, 2015, 5:05 am
Senior Member
 
mreuter's Avatar
 
Join Date: Jun 2011
Location: 53498 Bad Breisig, RPL, Germany
Posts: 375
Re: Strange wear caliper bolts

1+++

Have had the same Problem.
Bolt is over stretched.

Manfred
mreuter is offline  
 
post #4 of 17 Old Jan 19th, 2015, 8:44 am
Senior Member
 
dshealey's Avatar
 
Join Date: Apr 2002
Location: Dandridge (Near Knoxville), TN, USA
Posts: 12,165
Re: Strange wear caliper bolts

1++++

Gorilla tightened in the past. It is not worn, it is stretched. Tightened beyond metal's yield strength. Torque wrenches are your friend!

I don't want to achieve immortality through my work...I want to achieve it through not dying.

David Shealey
Dandridge, TN
EX: '01 Black LT, BAT BYKE (Totaled at 110,000 miles)
IBA SS, BB, BBG, 10/10ths.
No bike now, but maybe in the future.
dshealey is offline  
post #5 of 17 Old Jan 19th, 2015, 10:08 am
Senior Member
 
norton's Avatar
 
Join Date: Apr 2008
Location: Doylestown, Pa, usa
Posts: 787
Re: Strange wear caliper bolts

1+++++ I just wanted to outdo Dave's +'s. These guys know , they are several of the Mechanical genius's on this site.
norton is offline  
post #6 of 17 Old Jan 20th, 2015, 2:08 am Thread Starter
Member
 
Join Date: Jul 2012
Location: Voorst, , The Netherlands
Posts: 38
Re: Strange wear caliper bolts

That must have been done by the previous owner. It's a pitty.
Thanks for the answers.
tonvanunen is offline  
post #7 of 17 Old Jan 20th, 2015, 5:16 pm
Wrencher Extraordinaire
 
jzeiler's Avatar
 
Join Date: May 2004
Location: Hazel Green, AL, USA
Posts: 13,269
Re: Strange wear caliper bolts

The 2001 and up (BMW on the calipers) are 30 Nm with an M8 bolt. The earlier bikes were 40 Nm with an M10 bolt

John
2009 K1300GT Red Rocket
2009 R1200GS (Gone)
2005 K1200LT Ocean Blue Blue Wizard 110 K and counting...
2006 Bushtec Turbo+2 Spell
2004 330 Ci Convertable
K4AN

Have ridden a Motorcycle in all 48
But lack DE, MA, RI and CT with the 2005 LT

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
jzeiler is offline  
post #8 of 17 Old Jan 20th, 2015, 5:38 pm
Senior Member
 
sailor's Avatar
 
Join Date: Nov 2004
Location: Montreal ,QC , Canada
Posts: 1,171
Re: Strange wear caliper bolts

Quote:
Originally Posted by jzeiler View Post
The 2001 and up (BMW on the calipers) are 30 Nm with an M8 bolt. The earlier bikes were 40 Nm with an M10 bolt
John,
This is a very good point and is enough to damage these bolts. I can imagine a few getting confused - either:
(1) they use wrong chapter / section in CLYMER for their bike and get wrong torque specs (ABSII -vs-Integral ABS)

(2) they get on of these "free copy" of the K1200LT shop manual floating around the web - However they do not pay attention if manual version is for ABSII models (1999-2001) or for the next generation having IABS with BMW markings on calipers.
beech likes this.

-------------------------------------------------
John (Montreal, CANADA)
K1200RS (2002 IceBlue/Red - 96,000 miles)
-------------------------------------------------
Think twice before you hit [SUBMIT REPLY] - famous quote by another member:
"The value of this board is not founded on dismissing the ideas of others, but by posting to share our experiences and what we've learned from them."
sailor is offline  
post #9 of 17 Old Jan 20th, 2015, 7:21 pm
Lifetime Supporter
 
deanwoolsey's Avatar
 
Join Date: Aug 2008
Location: Topeka, KS, USA
Posts: 3,105
Re: Strange wear caliper bolts

Look on the bright side.
Those bolts are pretty cheap compared to the sliders.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
deanwoolsey is offline  
post #10 of 17 Old Jan 20th, 2015, 7:51 pm
Senior Member
 
GaryEm's Avatar
 
Join Date: Aug 2012
Location: Hudsonville, Mi., USA
Posts: 844
Re: Strange wear caliper bolts

TORQUE SPIECS.pdf

This might help if anybody is looking for how much torque to wrench on things

Gary
2003 K1200LT
GaryEm is offline  
post #11 of 17 Old Jan 21st, 2015, 4:56 am
Senior Member
 
mreuter's Avatar
 
Join Date: Jun 2011
Location: 53498 Bad Breisig, RPL, Germany
Posts: 375
Re: Strange wear caliper bolts

Very helpful thanks.

Manfred
mreuter is offline  
post #12 of 17 Old Jan 21st, 2015, 11:15 am
Guest
 
11862's Avatar
 
Join Date: Apr 2006
Location: minnetonka , mn, usa
Posts: 637
Re: Strange wear caliper bolts

This could be from a bad torque wrench, or bad torque spec, or bad conversion of torque spec (this happens a lot!). I is not likely bad bolts as these sort of fasteners are pretty carefully controlled in Germany.

Torque wrenches are usually so long-handled and they don't give any realistic feel to the mechanic.

Torque wrenches do not prevent a shade tree mechanic from doing crappy work. Sometimes they even help them do crappy work by giving a feeling of error invincibility.
11862 is offline  
post #13 of 17 Old Jan 23rd, 2015, 4:53 am Thread Starter
Member
 
Join Date: Jul 2012
Location: Voorst, , The Netherlands
Posts: 38
Re: Strange wear caliper bolts

Thanks voor the torque-specs. Didnt know there was a difference between the brembo en the BMW-calipers!!
tonvanunen is offline  
post #14 of 17 Old Jan 23rd, 2015, 10:33 am
Senior Member
 
dshealey's Avatar
 
Join Date: Apr 2002
Location: Dandridge (Near Knoxville), TN, USA
Posts: 12,165
Re: Strange wear caliper bolts

Quote:
Originally Posted by niel_petersen View Post
-----------------------------
Torque wrenches are usually so long-handled and they don't give any realistic feel to the mechanic.---------------------
One of the main reasons for using torque wrenches is to remove any need for "feel". You watch the gauge, or wait for the click, no "feel" necessary or needed.

I don't want to achieve immortality through my work...I want to achieve it through not dying.

David Shealey
Dandridge, TN
EX: '01 Black LT, BAT BYKE (Totaled at 110,000 miles)
IBA SS, BB, BBG, 10/10ths.
No bike now, but maybe in the future.
dshealey is offline  
post #15 of 17 Old Jan 23rd, 2015, 11:28 am
Guest
 
11862's Avatar
 
Join Date: Apr 2006
Location: minnetonka , mn, usa
Posts: 637
Re: Strange wear caliper bolts

Quote:
Originally Posted by dshealey View Post
One of the main reasons for using torque wrenches is to remove any need for "feel". You watch the gauge, or wait for the click, no "feel" necessary or needed.
And if you miss the click (or whatever) the OP pix above is what the bolt looks like afterwards..........
johnbaker15 likes this.
11862 is offline  
post #16 of 17 Old Jan 23rd, 2015, 9:42 pm
Senior Member
 
dshealey's Avatar
 
Join Date: Apr 2002
Location: Dandridge (Near Knoxville), TN, USA
Posts: 12,165
Re: Strange wear caliper bolts

Quote:
Originally Posted by niel_petersen View Post
And if you miss the click (or whatever) the OP pix above is what the bolt looks like afterwards..........
I have three different click type torque wrenches, and anyone brain dead enough to "miss" the click should not be working on mechanical things.
C-A-D and johnbaker15 like this.

I don't want to achieve immortality through my work...I want to achieve it through not dying.

David Shealey
Dandridge, TN
EX: '01 Black LT, BAT BYKE (Totaled at 110,000 miles)
IBA SS, BB, BBG, 10/10ths.
No bike now, but maybe in the future.
dshealey is offline  
post #17 of 17 Old Jan 24th, 2015, 5:40 pm
Enjoy The Ride
 
saddleman's Avatar
 
Join Date: Sep 2008
Location: Huntersville, NC, USA
Posts: 3,888
Re: Strange wear caliper bolts

Quote:
Originally Posted by dshealey View Post
I have three different click type torque wrenches, and anyone brain dead enough to "miss" the click should not be working on mechanical things.
I agree, I have twice had someone else use my 1/4" drive inch pound torque wrench & break off the square drive.

Dave Selvig
2004 Black LT
2000 Canon Red LT



To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
saddleman is online now  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the BMW Luxury Touring Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Strage front pad wear simon K1200LT 4 Sep 15th, 2010 7:51 pm
strange tire wear STARFIGHTER RT Series 5 Nov 11th, 2008 5:45 pm
Strange tyre wear simon K1200LT 10 Apr 25th, 2008 9:12 am
Would you die for a game console? eljeffe Chit Chat 10 Jan 16th, 2007 10:10 am
Strange front tyre wear myk_edwards K1200LT 15 Sep 1st, 2006 2:39 am

Posting Rules  
You may post new threads
You may 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 On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome