Welcome, Guest. Please Login or Register

Author Topic: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback  (Read 6502 times)

0 Members and 1 Guest are viewing this topic.

Offline Heimer

  • Global Moderator
  • Bachelor Dog
  • ***
  • Bike: BMW R1200GS
    Location: Western Cape
  • Posts: 12,778
  • Thanked: 125 times
  • Kan nie ALZ onthou nie
Re: BMW R1200 GS rear brake Caliper screws failure. Warning & feedback
« Reply #20 on: February 10, 2014, 06:12:37 pm »
Mine are fully threaded and never had an issue in almost ten years on two 1200's. I consider this thread unnecessarily alarmist claiming failure of the screws!

Dom - the screws don't fail - they loosen, pointing to a design issue

Le-Cap - thanks for your analysis. Thorough as usual

Presently I am guaging with whom else this has happened. I believe many people just kind od 'take it' as something they overlooked, or as normal wear.

I might be that work that was done, involving the removal of the calipers, led to incorrect torquing.

I will leave that part of the discussion for the gentleman (Dave Coetzee) when he provides his input, which I am waiting for by email. He had not done any work on his bike - it was done by dealers



My point exactly - YOU used the words "Caliper screws failure" in your subject heading! ... suggesting that it is the screws that are failing. I believe you should edit the title to at least have a question mark rather than it being a statement.

The screws will not loosen because they are threaded  - they will loosen due to HUMAN ERROR of not tightening to correct torque or over tightening compromising their tensile strength and stretching the thread. The "DESIGN ISSUE" is that of humans being fallible (ie often dof).

Yes professor, I did as you asked. Thanks for telling me. Do not lose hope with me yet.  8)

No hopeless cases only hopeless causes  :biggrin:  I still think the subject title should have a question mark after failure... it is a moot point at this stage ... a questions is being asked ... is there a design fault?

Dom the person who's information I am waiting for, asked me to do the post. He is an engineer and he reasons he would never use this type of screw for this application.

Le Cap seems to differ a bit about that

To it boils down to a possible design flaw, or human oversight in some cases.

That is why we are asking to whom else this has happened.

I don't know enough to debate the design aproach


Matriek getuigskrif 1979: ........... is 'n vriendelike seun met volop selfvertroue. Hy tree soms vreemd op. Die skool se beste wense vergesel hom.
 

Online BiG DoM

  • A Grahamstown Greyhound!
  • Bachelor Dog
  • *****
  • Bike: BMW R1200GS HP2
    Location: Eastern Cape
  • Posts: 17,674
  • Thanked: 224 times
  • License Plates: GSpot EC and HUSKY EC
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #21 on: February 10, 2014, 07:33:44 pm »
No issue with you Heim or putting the question out there - after all thats what a site like this is for. Lets see what the engineer comes back with. I can see why one may expect a shouldered bolt but would find it difficult to blame a failure on a fully threaded one torqued correctly.
"Love is the feeling you get when you like something as much as your motorcycle" - Hunter S. Thompson

Scoots: BMW HP2  Husky 701R  Husky  TE610E  BMW G450X  KTM 250XCW  Yamaha YZ250X BMW R100S YAMAHA BWS 

 :ricky:
 

Offline fun-24-7

  • Member
  • **
  • Bike: BMW R1200GS Adventure
    Location: Free State
  • Posts: 69
  • Thanked: 1 times
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #22 on: February 10, 2014, 09:14:02 pm »
My 2006 Adventure is now sitting at 101 000 kays, and I did not experience a similar problem of the bolts loosening yet. I must admit, though, that I stripped the one bolt head once when I removed them for changing the brake pads, and I replaced both with stainless bolts of the same thickness and lenght that I got from the local bolt shop. I never gave a second thought about the bolt strenght - very stupid indeed, after having read this thread. I will have to look into that immediately, but the question is how do I find out what the strenght is? There are no markings on the bolt as far as I know....
 

Offline capeklr

  • Senior Member
  • ***
  • Bike: BMW R1200GS Adventure
    Location: Western Cape
  • Posts: 1,202
  • Thanked: 8 times
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #23 on: February 10, 2014, 09:25:10 pm »
My 2006 Adventure is now sitting at 101 000 kays, and I did not experience a similar problem of the bolts loosening yet. I must admit, though, that I stripped the one bolt head once when I removed them for changing the brake pads, and I replaced both with stainless bolts of the same thickness and lenght that I got from the local bolt shop. I never gave a second thought about the bolt strenght - very stupid indeed, after having read this thread. I will have to look into that immediately, but the question is how do I find out what the strenght is? There are no markings on the bolt as far as I know....

As I mentioned earlier the tensile strength on the original bolt is 8.8.
The tensile strength number is on every decent bolt.
 

Offline Jondu

  • Senior Member
  • ***
  • Bike: BMW R1200GS Adventure
    Location: Western Cape
  • Posts: 1,027
  • .................................
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #24 on: February 10, 2014, 10:40:09 pm »
My fiets staan in die shop met die betrokke bout wat uitgeval het. Dit het gelukkig net na n trackday gebeur in Stellenbosch op stadigge spoed. Nie ek of enigge iemand weet wat die oorsaak is nie, maar die versekering en BMW stry nou. Ek hoop maar iemand betaal.
Die bout het nie gebreek nie, maar los gekom. Ek het egter die sling vervang en die bout getorque.
Ek hou dop wat julle sÍ en sal julle op hoogte hou wat gebeur het.
 

Offline Heimer

  • Global Moderator
  • Bachelor Dog
  • ***
  • Bike: BMW R1200GS
    Location: Western Cape
  • Posts: 12,778
  • Thanked: 125 times
  • Kan nie ALZ onthou nie
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #25 on: February 10, 2014, 10:42:53 pm »
Thanks Jondu.  Het jy gestem hierbo?

Matriek getuigskrif 1979: ........... is 'n vriendelike seun met volop selfvertroue. Hy tree soms vreemd op. Die skool se beste wense vergesel hom.
 

Offline Jondu

  • Senior Member
  • ***
  • Bike: BMW R1200GS Adventure
    Location: Western Cape
  • Posts: 1,027
  • .................................
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #26 on: February 10, 2014, 10:46:51 pm »
Yes.jy moet kom kuier as jy weer hier kom.
 

Offline Skipskop

  • Senior Member
  • ***
  • Bike: Kawasaki KLR 650
    Location: Eastern Cape
  • Posts: 2,929
  • Thanked: 6 times
  • ;-)
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #27 on: February 10, 2014, 11:30:59 pm »
Net n gedagte .Weet iemand of daar n springwasher of soortgelyk is wat moet keer dat die bout loskom. Ek het al gesien BMW ,nie bikes nie ,maar op karre en trokke, is lief om n dome spring washer te gebruik en as die verkeerd om angesit word is die werking nie effective nie .
Ek sal so droppeltjie locktight ansit as ek weer by my bike uitkom.
 
" Of all the things I lost in life, what I miss the most, is my mind"
DRZ 400 E ,1200GS WR450- KLR650 Side-car
Yamaha CV80 Beluga
"We do not quit playing because we grow old, we grow old because we quit playing"
"Old age is not for the inexperienced" "If you haven't grown up by age 50 , you don`t have to"
 

Offline Jondu

  • Senior Member
  • ***
  • Bike: BMW R1200GS Adventure
    Location: Western Cape
  • Posts: 1,027
  • .................................
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #28 on: February 10, 2014, 11:35:32 pm »
Ek het gedog locktite net vir die KLR's maar skynbaar is ek verkeerd. Ek dink dit is n uitstekende gedagte.
 

Offline Heimer

  • Global Moderator
  • Bachelor Dog
  • ***
  • Bike: BMW R1200GS
    Location: Western Cape
  • Posts: 12,778
  • Thanked: 125 times
  • Kan nie ALZ onthou nie
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #29 on: February 10, 2014, 11:45:12 pm »
Vir my is dit nog iets wat ek moet gereeld check

Loctite en torque van die caliper skroewe

Ek check ook bv. ander goed soos die sidestand se  skroef wat homself altyd loswoel


Matriek getuigskrif 1979: ........... is 'n vriendelike seun met volop selfvertroue. Hy tree soms vreemd op. Die skool se beste wense vergesel hom.
 

Offline AJL

  • Member
  • **
  • Bike: BMW R1200GS Adventure
    Location: Gauteng
  • Posts: 64
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #30 on: February 11, 2014, 12:14:30 am »
Nooit die probleem in 50000km op eerste fiets gehad nie.  Tweede fiets nou op 60000km en het op ongeveer 40000km opgemerk dat die caliper vassit.  Beide floater pins was vas 'geroes'.  Eerste tekens van 'n probleem was dat brakepads baie vinniger vervang moet word en natuurlik oorverhitting (van die pads/caliper/disc). 

Is dit moontlik dat die oorverhitting die effek van die 'locktite' (nie seker presies wat BMW gebruik nie) afbreek oor 'n tydperk en die heat-cycling dalk die boude laat loskom?

Ek check nou gereeld die caliper en maak seker die floater pins bly gesmeer en seŽls in goeie toestand.
 

Offline buzzlightyear

  • I'm Buzz Lightyear. I come in peace.
  • Forum Whore
  • ****
  • Bike: Honda CRF-1000L Africa Twin
    Location: Western Cape
  • Posts: 7,956
  • Thanked: 18 times
  • To infinity and beyond
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #31 on: February 11, 2014, 04:53:10 am »
maybe its an assembly/service issue rather than design? I agree a different design could prevent a very unsafe failure consequence.
"All that is necessary for the triumph of evil is that good men do nothing." (Edmund Burke)
 

Offline Raka

  • Vendor
  • Vendors
  • Senior Member
  • ***
  • Bike: BMW R1200GS Adventure
    Location: Gauteng
  • Posts: 1,525
  • Thanked: 7 times
  • Die Dominee
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #32 on: February 11, 2014, 07:44:59 am »
Ping , Welsh ! Any thoughts on this.....
 

Offline Welsh

  • BMW R1150GSV
  • Bachelor Dog
  • *****
  • Bike: BMW R1150GS
    Location: Gauteng
  • Posts: 17,687
  • Thanked: 377 times
  • Thunder Twonk. The two legged Twat Monkey.
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #33 on: February 11, 2014, 08:13:05 am »
Ping , Welsh ! Any thoughts on this.....

I prefer bolts with a shank, but technically no problem with a set screw in this application, it should be only in tension.

I think the biggest issue is that people dont torque them, remember if you overtighten them you will damage the threads in the aluminium, this may not strip first time, but they are damaged and stay that way, torque them properly and you shouldn't have issues, there are a lot of these bikes around and most "design" faults well recorded this isn't noted as one. 8)
Behind every great man, is a woman rolling her eyes.
 

Offline Heimer

  • Global Moderator
  • Bachelor Dog
  • ***
  • Bike: BMW R1200GS
    Location: Western Cape
  • Posts: 12,778
  • Thanked: 125 times
  • Kan nie ALZ onthou nie
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #34 on: February 11, 2014, 08:16:09 am »
Ping , Welsh ! Any thoughts on this.....

I prefer bolts with a shank, but technically no problem with a set screw in this application, it should be only in tension.

I think the biggest issue is that people dont torque them, remember if you overtighten them you will damage the threads in the aluminium, this may not strip first time, but they are damaged and stay that way, torque them properly and you shouldn't have issues, there are a lot of these bikes around and most "design" faults well recorded this isn't noted as one. 8)

I hear you.

And if the bike was always serviced by a dealer, are we saying the dealer is accountable for the screw undoing itself ?
« Last Edit: February 11, 2014, 08:19:27 am by Heimer »

Matriek getuigskrif 1979: ........... is 'n vriendelike seun met volop selfvertroue. Hy tree soms vreemd op. Die skool se beste wense vergesel hom.
 

Offline King Louis

Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #35 on: February 11, 2014, 09:33:48 am »
Did happen and was discussed on the German forum. General consensus was that in all probability it goes back to incorrect fitting when putting the bolt (they actually call it a screw, not bolt) back.

Various reasons: no warming up of the screw when loosening (!) - must admit, didn't hear that one before...
No proper cleaning of the thread on the screw and the caliper, any residue may affect the proper sitting of the screw
Incorrect use of the torque wrench
Over tightening of the screw
Torque wrench faulty (how old is yours, when did you last calibrate?)
Most use loctite (blue)

It happened to both rider categories, i.e. those that service themselves and those that use dealers exclusively. Very few cases were reported and considering that hundreds of thousands of these bikes are sold worldwide, it can probably be put under the odd one out and not under the panic making press statement that these bikes are natural killers.
 

Offline ClimbingTurtle

  • Forum Vendor
  • Forum Whore
  • ****
  • Bike: BMW (all models)
    Location: Gauteng
  • Posts: 7,207
  • Thanked: 251 times
  • Give It Horns - Save Our Rhino's
    • Majita Tool Supplies
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #36 on: February 11, 2014, 09:39:53 am »
Various reasons: no warming up of the screw when loosening (!) - must admit, didn't hear that one before...

You need to heat the bolt if Loctite was used - it causes the Loctite to "fail" and makes the removal of the bolt easier....

For Info - you also get high-heat resistant Loctite as well - wouldn't recommend it for this application tho....
www.majita.co.za - we sell tools!

"And if I knew I was going to be this thirsty, I would have drunk more last night"

2010 R1200GS Adventure SOLD - 2007 BMW G650x - 1981 XT500 - 1980 XT500 - Gone to Mud Island for a better life with Roadcat the Lordly, Keeper of the Mead...!
 

Offline Takashi

Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #37 on: February 11, 2014, 09:58:35 am »
I mark all the very important bolts on my bike with a tamper seal. (Pretty much red nail polish)

This gives you a visual indication of a bolt coming loose.
 

Offline Welsh

  • BMW R1150GSV
  • Bachelor Dog
  • *****
  • Bike: BMW R1150GS
    Location: Gauteng
  • Posts: 17,687
  • Thanked: 377 times
  • Thunder Twonk. The two legged Twat Monkey.
Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #38 on: February 11, 2014, 10:20:55 am »
OK, I admit I know bogger all about 1200's but:

1) they are screws, by definition a bolt has an unthreaded shank, a set screw is fully threaded.
2) the 1150 does not use loctite on these screws, so I am not sure why these would?
3) I would not loctite as if you need to remove it without workshop facilities (heat gun) you can damage the aluminium threads by winding it out, then you will have problems with it coming loose.
4) I also mark them with a spot of paint as a visual indication, as well as oil filler/drain plugs and parralever pivots/locknuts.
5) I have a specific 3/8" drive torque wrench 20/ 80Nm with socket allens for this.
6) DO NOT USE COPPASLIP on this nor on the wheel bolts!

So IMNSHO pay your money for a good wrench, torque it nicely and no dont use locktite!!

There was a similar spate of rear wheels falling off 1150's they could all be traced, to incorrect torquing (as in not at all) or people using coppa slip on the bolts they should be fitted dry!!!  
  

« Last Edit: February 11, 2014, 10:22:52 am by Welsh »
Behind every great man, is a woman rolling her eyes.
 

Offline Takashi

Re: BMW R1200 GS rear brake Caliper screws design issue. Warning & feedback
« Reply #39 on: February 11, 2014, 10:30:16 am »

6) DO NOT USE COPPASLIP on this nor on the wheel bolts!

There was a similar spate of rear wheels falling off 1150's they could all be traced, to incorrect torquing (as in not at all) or people using coppa slip on the bolts they should be fitted dry!!!  

I started using copper slip on my rear wheel bolts when I snapped the torx bit trying to remove the wheel.
Previous torque was done when I replaced tires, now I torque my own wheels.
I use very little copper slip and mark the screw when tightened to the correct 60Nm.

Is the 1150 screws also countersunk?