BMW response on fork bolts

[sproggy]

Well said, Dickie!

I just had a thought while reading your post. Not being where my bike is right now, do the yoke pinch bolt holes go all the way through? If we could use a longer bolt and put locknuts on the end...

No - they're blind holes.

Having looked through the threads and read all the posts I have come to one simple conclusion ... you are going to get some tosser killed if you keep it up ... this just isn't funny anymore ... if your fork pinch bolts are coming loose then take the damn thing back to the dealer ...

I don't see that complaining about bolts being loose when they shouldn't be is going to get anyone killed, neither is tightening them up to the factory specified torque setting, once or a thousand times. It's good for your customers that none of the bikes you've seen suffer from this problem. However many others clearly do, mine included. Personally I haven't got time to go running to my dealer every few days - I own the necessary tools and can and will do it myself. The point is, they should never have been loose in the first place, not after 1300 miles or 13,000. As long as BM and their dealers continue to insist that this isn't an issue all they're going to do is re-torque the bolts and send people on their way. This level of service can be replicated in my garage with considerably less inconvenience!

The real concern is the owners who DON'T read this forum (there must be plenty of them) and are blissfully unaware that their fork bolts might be loose (or even missing by now) because BM refuse to issue a recall on them. Worry about those people - not those of us here who are already aware of the problem and can make our own decision about how to tackle the it.

 

[sjwb]

Whatever is happening (alledgedly) to lower yoke pinch bolts, is certainly not a design flaw. The issue is one of process - if it exists at all - and I am NOT convinced that it does.
If the bolts (like every other) are secured correctly and if necessary with Loctite, they will not come loose.
It worries me that people post information with little or no qualifcation regarding duty cycle, tooling, method and most of all rectification.
The lack of expertise and plethora of alegorical disinformation is rampant on this forum (like any other) and people should be very carefull to whom they listen (including myself). I refer more specifically to the repeated crap regarding oil type, oil consumption and the one that really astounds me - running in.

 

[piebaps]

Well said Ste. good to see that dealers are taking note and if I am ever in Southport I will pop in and buy something. You guys seem switched on.

 

[Malcvtr]

Whatever is happening (alledgedly) to lower yoke pinch bolts, is certainly not a design flaw. The issue is one of process - if it exists at all - and I am NOT convinced that it does.

I'm happy to take your expert opinion. What is happening then to all these owners who report these bolts loosening - some with alarming frequency? Are they all doing something wrong? An expert explanation of the phenomenon would be greatly appreciated.

If the bolts (like every other) are secured correctly and if necessary with Loctite, they will not come loose.

How will I know if Loctite is necessary? Perhaps if the bolts keep coming loose on their own? But if the bolts keep coming loose on their own, isn't that a design flaw?

I refer more specifically to the repeated crap regarding oil type, oil consumption and the one that really astounds me - running in.

Again, and I'm not being funny, can you give us the definitive comments on each of these then? I certainly don't want to listen to repeated crap. Ta muchly.

 

[Ste@SSB]

Well said Ste. good to see that dealers are taking note and if I am ever in Southport I will pop in and buy something. You guys seem switched on.

Thanks ... do come by for tea and biscuits (oh erm ... bring biscuits)...

Anyway ... I have talked to a few people today and the general opinion seems to be that there is a possibility that one of either pair of fork pinch bolts could be slacker than the other ... this could be due to them being gunned up in the factory and the last bolt slackens the first bolt (as mentioned by another poster) ... all bikes are checked when they are built up and none have come loose since...

sjwb seems to be making sense to me ... this site is full of information ... more information than is required in some cases ... its all here from the marvellous ... to the downright criminally stupid ... some posters on here seem to want to be the one who finds the ultimate fatal flaw that will destroy the world and kill us all ... this isn't it ... you can take a pinch bolt out of either side and poke em' were the sun don't shine and it still won't make you crash your bike...

Still ... only my opinion...

 

[sproggy]

Did you do the re-torque like I suggested? If so, I am hoping that it takes care of your issue. Would you be kind enougth to keep us posted on this?

Only 140 miles since my re-tightening (re-torquing back and forth between bolts), but I just got back from holiday and checked the bike over last night before using it this morning. Wasn't going to check the pinch bolts (how paranoid would than be after so few miles ) but the torque wrench was handy, so......

Bottom right bolt, half a turn to return to correct torque setting, top right bolt about 3/8 turn. Bottom left bolt half a turn, top left bolt was fine.

I'm not drawing any conclusions here, simply stating facts. I'm not going to try using Loctite unless I get confirmation from the dealer that this is appropriate since, as someone else pointed out, the presence of Loctite on the threads could act as a lubricant and affect the apparent torque.

140 miles is about 3 days commuting, I wonder how loose they'd have got if I'd been reckless enough to leave them unchecked for a week So the bolts stayed tight for less distance that I can cover on a tank of fuel I carry my other half on the back of the bike every day. It bothers me.........

 

[Emoto]

Only 140 miles since my re-tightening (re-torquing back and forth between bolts), but I just got back from holiday and checked the bike over last night before using it this morning. Wasn't going to check the pinch bolts (how paranoid would than be after so few miles ) but the torque wrench was handy, so......

Bottom right bolt, half a turn to return to correct torque setting, top right bolt about 3/8 turn. Bottom left bolt half a turn, top left bolt was fine.

I'm not drawing any conclusions here, simply stating facts. I'm not going to try using Loctite unless I get confirmation from the dealer that this is appropriate since, as someone else pointed out, the presence of Loctite on the threads could act as a lubricant and affect the apparent torque.

140 miles is about 3 days commuting, I wonder how loose they'd have got if I'd been reckless enough to leave them unchecked for a week So the bolts stayed tight for less distance that I can cover on a tank of fuel I carry my other half on the back of the bike every day. It bothers me.........

Distressing.

Do you think there is a chance that your torque wrench is off and not supplying all the torque that you are asking of it? Just wondering.

 

[sproggy]

Distressing.

Yes.....

Do you think there is a chance that your torque wrench is off and not supplying all the torque that you are asking of it? Just wondering.

I think it's unlikely that it would be so inconsistent over the period of a week or so. In an attempt to introduce some 'control' I'd put a jubilee clip around the adjuster when I first torqued the bolts up so that (because I slacken it right off between uses) I could put it back to exactly the same setting the next time. So I reckon the wrench was set as close as possible to the previous setting.

Also, if the torque wrench was 'off' it should have been off by the same amount on each bolt, which it wasn't - one bolt was OK and the others differed in how much they needed tightening.

I'd be the first to admit that it wasn't a completely controlled experiment but it was as close as was feasible.

The next thing I'll try is re-checking them tonight (another 50 miles may have affected them ) and then applying paint marks to provide a visual indication of any movement. Someone suggested that they might loosen off without actually rotating (although I can't imagine there's that much 'give' in the aluminium of the yolk) - this'll be the next check to make.

 

[WindyChuffer]

Why don't you torque the bolts up and then put a paint stripe on the bolt and the fork.

That way if the bolt has moved, then you will see the mis-alignment of the stripe, and the presence of a problem. Theres no retorquing required on a routine basis, just a quick visual to add to the pre-ride check.

Am sure a lot of this is a perceived problem arising from persistant re-torquing of bolts, but could be wrong.

My new GSA came with paint stripes as above, and they ain't moved yet...

Would be interesting for those who think they have a problem to try this as an experiment for a few thousand mile, and then review the results. This will really determine if there is an actual problem and the extent of it.

 

[sproggy]

Why don't you torque the bolts up and then put a paint stripe on the bolt and the fork.

Er, like I said....

The next thing I'll try is re-checking them tonight (another 50 miles may have affected them ) and then applying paint marks to provide a visual indication of any movement.

 

[WindyChuffer]

oops - not sure what happened here but cant delete this resposne...

 

[Emoto]

Yes.....



I think it's unlikely that it would be so inconsistent over the period of a week or so. In an attempt to introduce some 'control' I'd put a jubilee clip around the adjuster when I first torqued the bolts up so that (because I slacken it right off between uses) I could put it back to exactly the same setting the next time. So I reckon the wrench was set as close as possible to the previous setting.

Also, if the torque wrench was 'off' it should have been off by the same amount on each bolt, which it wasn't - one bolt was OK and the others differed in how much they needed tightening.

I'd be the first to admit that it wasn't a completely controlled experiment but it was as close as was feasible.

The next thing I'll try is re-checking them tonight (another 50 miles may have affected them ) and then applying paint marks to provide a visual indication of any movement. Someone suggested that they might loosen off without actually rotating (although I can't imagine there's that much 'give' in the aluminium of the yolk) - this'll be the next check to make.

Oh, sorry, wasn't trying to point out that this wasn't a precise laboratory experiment. I think what you're doing is a valuable exercise. And, I agree with you about a drop of paint where the bolt head meets the yoke.

The only thought I can offer about the torque wrench is if it was reading higher than it was torquing (say it read 10 ft/lbs, but was only imparting 7 ft/lbs to the fastener) then, it could be the case that the lower fasteners might be subjected to different stresses based upon how the suspension transfers them through the yokes, so might be expected to differ. The up and down action is one thing, and the side loads from riding on crowned roads are another. I'm just brainstorming here. Could be completely wrong...

 

[sproggy]

Actually I realised after I'd replied that I'd misunderstood what you'd said. It is possible that my torque wrench is out by an unknown amount - perhaps I ought to look at ways of getting it callibrated or at least borrowing a friend's wrench to compare.

I haven't done the paint thing yet but I'll borrow another torque wrench before I do, just to compare the settings. As you say, if I'm not doing the bolts up tight enough in the first place it's not surprising that they'd come undone. Of course that doesn't explain why they were loose in the first place.....

 

[Emoto]

How's it going, Sproggy? Any news about the bolts or anything?

 

[sproggy]

How's it going, Sproggy? Any news about the bolts or anything?

To be honest I haven't checked the bolts - I've just been riding the bike. I should get around to checking and paint-marking them, but...... Maybe this weekend.