Fork Pinch Bolts poll.....let's quantify the problem.

I own a 1200GS and I have checked my pinch bolts to find;

  • Total voters
    88
  • Poll closed .
thornley said:
No 'welding' takes place at the macroscopic or other scale between your mouse and the mat.Newton describes it somewhat better than your quote. As I said before auguments are meaningless if the bolts come loose. A solution or at least an investigation leading to one needs to be carried out.
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I'm with Motomartin, if you took a previously 'sterile' mouse and mouse mat, put them together in the usual fashion of mouse on mat, seperated them and sent them for forensic analysis you would find traces of mouse & mat and vice-versa, that transferance HAS to produce friction from attraction even if the two componants were so placed on the periodic table as to be inert. The 'welding' can be physical, chemical, magnetic, ionic whatever, probably a combination, but it will be there.
 
Hi Please change my vote, I screwed up and voted for "No bolts loose". It should of been "all Four Loose".

I first checked them with just a screw driver. I then went back with a 3/8 drive ratchet. But, they might of been to spec. I don't have a Torque Wrench. (A buddy who a Mechanic told me that the average pull on a wrench is 35 lbs of torque.)

I guess it's time to get a torque wrench now.

Thanks

North
 
Transferance quite possible, increase of friction as a result, possibly but welding in the original context of my post i.e galling between threads leading to fusion of the materials no. The issue here is still loose nuts
 
Fanum said:
This poll is only for 1200 owners please......

If you have checked your fork pinch bolts, please vote and we'll see what proportion of 1200 owners have a problem.

If you haven't checked, or don't know what I'm on about, please read these two threads, check your bolts and then vote;


http://www.ukgser.com/forums/showthread.php?t=54618
http://www.ukgser.com/forums/showthread.php?t=55146

Please note that we are able to check IP addies, this poll is public (IE who votes can be seen) and this is a serious matter....we want to find out what proportion of 1200's have this problem, not indulge in wind ups or slagging off BWM's....ONLY VOTE IF IT'S GENUINE
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This is not going to be meaningful unless everyone uses exactly the same procedure and identical calibrated equipment.
 
Engineer said:
This is not going to be meaningful unless everyone uses exactly the same procedure and identical calibrated equipment.
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It may not be as accurate as a scientific test, but a finger loose bolt (as has been described by some people) is a very loose bolt regardless of what torque wrench or technique was used to discover it.

The degree of looseness we're concerned about doesn't require fully calibrated equipment or set procedures.....so I disagree, it's not meaningless ;)

If you have any better ideas though, feel free to suggest them...... :D
 
Fanum said:
It may not be as accurate as a scientific test, but a finger loose bolt (as has been described by some people) is a very loose bolt regardless of what torque wrench or technique was used to discover it.

The degree of looseness we're concerned about doesn't require fully calibrated equipment or set procedures.....so I disagree, it's not meaningless ;)

If you have any better ideas though, feel free to suggest them...... :D
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Let me give one example of where there might be a big problem with this.

What is meant by a "finger loose" bolt? Do we all understand this to be the same thing? My understanding of "finger loose" is that the bolt could be turned with the fingers only without the aid of any tools - is this what everyone means? Or do they mean it could be turned with finger pressure on the end of a socket wrench?

This may sound very pedantic - but I have investigated lots of reported engineering problems over the years and very often the initial description bears very little resemblance to what is actually happening when the problem is properly investigated.

If the bolts can be turned with finger pressure only applied directly to the bolt head then there is a serious problem - but is this really the case? (assumming of course that the person turning the bolts is not Superman!)

To some people it may sound as if I'm being ridiculous but unless we are all talking about the same thing then any results really are meaningless.
 
I agree with the need for accuracy, but in 32 years of Engineering I have never heard of 'fingertight' being used to describe the use of a spanner. But as others have said, pendantics are not the issue, safety is the issue and clearly there is a problem for bwm to address. The requirement for detailed, accurate measurement should not, at this stage, be allowed to mask the fact that an extrordinarily high percentage of vital fasteners are not remaining secure between standard service intervals - the very lowest acceptable standards unless the manufactures have SPECIFICALLY identified these componants as requiring re-torque between service intervals.

Put simply, have bwm made clear that, in addition to full dealer servicing, any new owner MUST purchase a calibrated torqe spanner for ongoing safe use?
 
riverking said:
I agree with the need for accuracy, but in 32 years of Engineering I have never heard of 'fingertight' being used to describe the use of a spanner. But as others have said, pendantics are not the issue, safety is the issue and clearly there is a problem for bwm to address. The requirement for detailed, accurate measurement should not, at this stage, be allowed to mask the fact that an extrordinarily high percentage of vital fasteners are not remaining secure between standard service intervals - the very lowest acceptable standards unless the manufactures have SPECIFICALLY identified these componants as requiring re-torque between service intervals.

Put simply, have bwm made clear that, in addition to full dealer servicing, any new owner MUST purchase a calibrated torqe spanner for ongoing safe use?
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Of course the majority of Engineers and Technicians know (or should know!) what finger tight is - do those who claim to have bolts that loose really mean the same thing - how can you be certain?

Are you saying that we know for a fact that some owners have bolts that are so loose that they can be turned by fingers only? Where is the unequivocal evidence.

Detailed accurate measurement IS essential otherwise you only have a collection of words that people have typed into an internet forum!

Have BMW really said that owners must have a calibrated torque wrench to maintain safe operation of their vehicle - is it in the manual? Perhaps I missed that bit, but would be surprised if that was the case.

Sorry to be pedantic again - but you DO NOT really know that an extaordinarily high percentage of vital fastners are coming loose - You may be right but you do not know it and this survey is not sufficiently accurate to answer the question.

It is so easy for one or two people to report a problem (real or otherwise) on an internet forum and then for the whole thing to get totally out of hand through lack of knowledge, rumour, misunderstanding etc.

Sorry to be a pain - but I have never seen so many scare stories as I have on this site - and I find it hard to believe that BMW motorcycles have so many problems.
 
Sorry to be pedantic again - but you DO NOT really know that an extaordinarily high percentage of vital fastners are coming loose - You may be right but you do not know it and this survey is not sufficiently accurate to answer the question.
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You're right Engineer, it IS innaccurate and with the fudge factors involved in deciding how loose 'finger tight' actually was, to what degree the guy's torque wrenches are out by etc etc, it's not scientific and it wouldn't for example be useable in a court of law.

It IS however, the best indication that we have right now that there IS a problem with these bolts- how much of a problem exactly and the 'fuzzy factor' of how loose was loose and the calibration issues may not give us a totally accurate picture but it's the best we've got, and even allowing for this 'fuzzy factor', I think it's pretty clear that an unacceptably high number of 1200GS's do have an issue with them.

FWIW, I used to be a Patrol Team Manager with the AA, and part of my job was doing a yearly calibration and certification of the torque wrenches of every patrol in my team.......they may well have been a few NM out (particulalry at the highest and lowest ends of the range) but they rarely went 'out' by more than about 5-7%, unless they'd been severly abused and dropped/driven over etc.

The range we're considering here as a definition of 'loose', even with T.W's that probably have never been calibrated, is from 15% loose and upwards (based on reporting anything under 21nm as 'loose').

Like I said, it's the best we've got or can do in the circumstances.
 
Engineer I think you are wrong (in a nice way :) ) Not technically inaccurate, but wrong.
Why? Because more than one person has come off their bike in very 'unusual circumstances'. They have gone to their dealers, and so far the dealers have not accepted that there MAY be a problem with loose pinch bolts as discovered by the owners themselves.
Many other forum members, some Engineers like you and I, some Technicians, some Mechanics, some good DIY, some clueless, have said that they have similar 'loose' pinch bolts.

Many of those assessments will be wrong, many will be inaccurate, few if any will be very accurate. But I will put a lot of money on the ability of the above group to check and assess whether or not the wheel nuts on their car were basically loose or basically tight.

This poll cannot, and is not intented to, make a professional assesssment of the pinch bolt problem (if there even is a problem). It is intended to ring an 'early warning' bell to the fact that something MAY be amiss. For that to happen, accuracy is not required as I said "at this stage".

The alternative is to wait until the number of serious accidents makes it impossible for the manufacturers to deny the problem, as has so often been the case in the motor industry in the past - fix technical problems when the cost of lawsuits is likely to exceed the cost of recall. (that is NOT a critism of mbw, simply a reflection on the history of the motor industry).

Unfortunatly the detailed accuracy that you are asking for usually only presents itself post event - often in the Coroners Court. The lads are indeed 'jumping the gun', they may well be wrong, but even if there IS a problem, it is not one that is going to cost a fortune to put right, a simple fix is available, and it may, just may, save a couple of Tossers on here from serious injury.
Cheap check, cheap fix, potentially massive benefit. No brainer for me.

I have personally used torques in excess of 100,000 lb/ft where the consequences of bolt failure would be another Chernobyl, I am not therefore going to get overexcited about a couple of motorcycle pinch bolts. But where so many (75%) are saying that they MAY have a problem, why wait, what is the benefit? Operation of closure devices in a time and spacial relationship to the movement of the horse may be relevant in this instance.
 
Dahoum me old fruit, would you mind exerting your new found mod powers and adjust the 'none loose' vote down one and the 'all four loose' up by one for North please (ref earlier in the thread when he said he'd got it wrong).

Could you also lower the 'all four loose' by a further one as Pint 'the wanger' 6x doesn't to my knowledge have a 1200 and was merely attention seeking as usual :rolleyes: :rolleyes:

Many thanks

B
 
riverking said:
........But where so many (75%) are saying that they MAY have a problem, why wait, what is the benefit?...........
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This is the problem - your are using fundamentally flawed data to to justify an action. Statistics like this are the reason why the phrase "lies, damned lies and statistics" was coined.

If someone thinks that they may have a problem then an owners forum like this is a great place to ask questions and inform others, but without very careful testing one cannot conclude anything more than one or two people may have had a problem that may or may not have been related to the pinch bolts.

If we are not careful then we are in danger of starting another ABS scare story without any real evidence.

You could argue that it's better to be safe than sorry, but do we all want to exist in a total state of paranoia brought on by heresay and dodgy science.


My apologies again for being an awkward cuss - I'll shut up now :-)
 
just lateraly thinking about this for a minute.

I'd bet all the bolts are torqued up on a production line somewhere ( with a calibrated air ratchet ) - and then what 'should' happen is mr BMW mechanic ( or bike builder ) at the dealer will go round and do a spanner check on the critical bolts.

Now - in my experience - Jap bikes are delivered to dealers with the forks off at the headstock - i don't know about BMW. If they are like this these should be checked by said builder /mechanic.

If not , all bolts should be checked at PDI stage - Hondas certainly have a 'tick list' that has to be signed by the mechanic who does the PDI to say all the critical bolts have been checked for tightness.

Lets say all that has actually happened and the bolts are still becoming loose. It could then be torque relaxation due to material deformation. Ally fork clamps are softer than the bolt bead for instance. This could be due to not enough material area available under the bolt head - which is a design issue. No end of loctite can help here.

But - i'd still say that this is a dealer PDI / mechanic issue, based on timescales of bike newness.
 
I agree with Motormartin's last points on this, the issue now is not if their is a genuine problem or if there is a perceived problem, either way it is a problem. Accuracy of the torque readings or definitions of tightness/looseness are rapidly becoming irelevant. If its real it is a potentially dangerous situation, if its perceived its a possible hit on sales and reputation. The dealers can hit this and be seen as being pro active. How long before R1200 GS's are seen as deathtraps regardless of the true facts? reality is reasonably easy to quantify, perception of a product or service goes on and on.
Lighter note anyone know where to buy shares in a torque wrench manufacturer?
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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