cross-threaded pannier mounting point

[Box of Frogs]

Oh noooooooo
I was fitting the side-pannier frame to my wife's F650GS last night and one of the bolts felt a bit stiff and wanted to enter at an angle other than 90 degrees. So, I removed the bolts we'd finger-tighted so far, removed the frame, and tried to get a bolt into the problem hole.
I could see the thread didn't look perfect, and the bolt wanted to twist almost as soon as I started turning it in. I held my thumb against it to keep it perpendicular and managed a few turns - feeling confident that I was 'cleaning' the thread by turning the bolt through it I carried on but agter a few turns the bolt wanted to go off-straight again. I decided to take it out, but horror of horrors the threaded insert in the frame is now just turning in place!

We're off to France on Wednesday, the shop we bought the bike from is closed on Sunday (today) so we're left with the possibility that the £600 worth of panniers won't get used for what may be the last big trip of the year.

Any ideas?!? How are the inserts normally held firm?

Thanks.

 

[freeloader]

Can't offer any help, but more information would help; such as, which panniers are these (BMW Vario? BMW aluminium? other?), where in the frame is this threaded insert, and a photograph of it too if possible. The more information you can give, the better!

 

[ILMV]

Does the thread go all the way through... could you pass another bolt through the other side to push the stuck bolt back out again, and hopefully straighten out the tread again.

 

[v8legend]

Without a pic it's hard to diagnose your problem. If you have access to the back of the mount, you could use a longer bolt and a nut behind.

My guess is that you have the same problem as one of our cousins from accross the pond recently. He stripped a thread whilst fitting a rack. These threaded inserts are known to me as Rivetnuts, and are easily available. I think I might even have the tool somewhere. As the name suggests, they are a kind of rivet, which when compressed, leaves a threaded nut. You need to work out what thread you have, drill it out, and fit (or get fitted) a new one. It's actually very quick and simple if you have the right tools.

 

[siwhite]

Rivnuts (sometimes called nutserts) are a beautiful invention which can turn into a nightmare when they go wrong. I've had exactly the same problem as you are describing on my F800.

The real problem is that, when the thread strips or distorts, they are effectively impossible to remove from inside a 'blind' section of frame. I recommend a repair of your current rivnut.

First things first - you need to stop it spinning in the hole. Rivnuts have a knurled underside designed to stop them spinning, and this is likely to have failed.

Give the rivnut a good dose of superglue around where it enters the frame. The idea of this is to stop it turning when you clean the thread in the next step.

Use a thread cutting tap of the correct size to clean the thread. Turning the tap will make the rivnut want to turn, which is what the superglue is trying to prevent. Note that adhesives are poor in shear load situations like this, so go easy on the tap or help the glue by holding the rivnut with some long nose pliers while you use the tap.

Now you should have a good thread in the rivnut, but the rivnut will still be loose in the frame. You have three choices! Either but a rivnut tool (£30 - rather a lot for one use) or buy an elegant tool from ebay...

http://cgi.ebay.co.uk/Rivnut-Rivetnut-Nutsert-Fitting-tool-M4-M5-M6-Kit-car-/170553023698

...which is also a lot of money but the link gives some good info about what you are trying to achieve.

Best solution is a DIY hack like this...

Have a bolt of the correct thread, then a nut, then a bit of plate with a clearance hole, screw the bolt into the rivnut and tighten, all the while counterholding the nut. The rivnut should clamp up nicely.

Google 'DIY Rivnut' for a wealth of info.

 

[chas820]

I had the same thing when i was fitting pannier racks.It`s the riv nut under neath looking up.Mine wasn`t cross threaded just loose in the sub frame and just revolved with the bolt.They are almost impossible to get at as you can only see the edge.Bmw replaced the sub frame under warrenty.

 

[Box of Frogs]

imaginitive

Well, panic over for now.
Thanks for the replies.

Because I had tried to thread the bolt into the nut and it got stuck I couldn't get at the edges of the nut near the frame so was worried that I would have to get the bike to a dealer for a sub-frame replacement (as Chas820 had to do).

In answer to the several 'can you get at it from the inside?' - no, it box frame with no way at it.

What I decided to try was:

Saw off the hed of the stuck bolt (using the metal saw of a swiss army knife) - this took ages :-(

Then, I could fit the pannier frame (for the BMW variable all-black panniers) over he sawn bolt and at least fastne all the othe fixings. My thinking was to find a nut to tighten over the sawn bolt and I'd be ok.

Well, I got the whole frame fitted without any further problems and couldn't believe that the 2 lock-nuts that were supplied were spare - they are for a different type of rear sub-frame attachement than our bike. Amazingly, one of these threaded easily onto the sawn bolt and I could get a socket in to tighten it - why the sawn bolt didn't just turn in place I don't know, nor do I care.

Time for a beer me thinks

 

[chas820]

Oh you lucky man