ball joint, loose threads

[parishollow]

I installed Works shocks yesterday. While buttoning it all up I noticed a tiny bit of play in the front wheel. Having it sitting on the center I can move the front wheel forward and back and feel a little movement where that big nut screws down into the brace between the forks. Further investigation I found I could move the nut with my fingers while rocking the tire back and forth. This is supposed to be torgued to 230nm! How do I now torgue this thing while it is on the bike? Is this reasonable or do I need to take it all apart? Kind of scary that I can turn it with my fingers even though only a couple threads are not screwed in.
BTW, the new shocks feel great! However on the way home from testing them out my clutch is now slipping. Only 54k on the bike! ARGG!

[Dman]

Andrew,

The fact that said parts are steering / suspension componets, I would remove the ball joint / fork bridge assembly, take it apart and inspect the threads for damage. It's probably OK but.................................. (Don't think we need to expound on the importance of these parts, do we?) And while apart, the torque can be done properly.

BTW, By the looks of your recent posts it appears that you and "Murphy" are gettin kind of cozy. Try to stay away from that guy!!!!!!!!!!!!!

Good Luck

[mneblett]

Further investigation I found I could move the nut with my fingers while rocking the tire back and forth. This is supposed to be torgued to 230nm! How do I now torgue this thing while it is on the bike? Is this reasonable or do I need to take it all apart?First thing: "take it all apart?" -- probably don't need to. BUT, what you do need to do is verify that the hole in the telelever isn't "wallowed out." The hole is smooth-sided, corresponding to the smooth sides of the lower portion of the ball joint stud. If the joint has been loose for any length of time, there is the possibility that ball joint stud has been pivoting fore/aft in the hole, hammering the top and bottom edges of the hole. If fore/after deformation of the hole is negligible, you can just tighten the nut back up, but if it's more extensive, and you have any question as to whether it will rigidly hold the stud without *any* motion, then the right thing to do is replace the telelever itself (not a fun job -- see my posts from June/July last year).

As for torquing, the manual sez use a special tool which allows you to insert an Allen wrench into the end of the stud while applying the torque. You can do it in two steps without the special tool. First, use an Allen to keep the stud from rotating while you use a regular box-end wrench to get the nut pretty tight. Second, remove the Allen wrench, mark the stud so you can tell whether it has rotated, then apply your torque wrench w/o the Allen. When I did it this way, the first step left the stud tight enough that it didn't rotate further during the final torquing.

[mobygrape]

If you are talking about the actual ball joint where it threads into the lower fork bridge, you need to remove the bridge and inspect the threads and the hole for damage. If all is ok, than retorque it and put it back together. If there is any damage, I would replace the bridge. It is aluminum, and I don't think that it would take long for play there to hog it out. I would certainly replace it and the ball joint if it were a warranty repair, or my bike.

[mneblett]

If you are talking about the actual ball joint where it threads into the lower fork bridge, you need to remove the bridge and inspect the threads and the hole for damage. If all is ok, than retorque it and put it back together. If there is any damage, I would replace the bridge. It is aluminum, and I don't think that it would take long for play there to hog it out. I would certainly replace it and the ball joint if it were a warranty repair, or my bike.Thanks, Paul -- Obviously, I assumed the stud nut, not the ball joint; the 230 Nm should have been a tip-off.

FWIW, I had the choice of replacing the ball joint or the entire assembly after my front-ender. After looking at all the options, even with a straight original lower fork bridge, I replaced the whole thing -- I just didn't trust re-torquing those relatively small threads.

[mobygrape]

Sometimes when you order a lower bridge, it comes with a ball joint installed already. Usually not. It keeps you guessing. There is a fixture to hold the bridge when torqueing the ball joint, but I think it can be done in a vise using soft jaws. 230 nm is pretty high, so it needs to be secure. Resist the impulse to use locktite here, or plan on buying a new bridge when the ball joint wears out. This is the second occurence of this problem reported in about a month. Interesting.

[km5bh]

I noticed a tiny bit of play in the front wheel. Having it sitting on the center I can move the front wheel forward and back and feel a little movement where that big nut screws down into the brace between the forks. Further investigation I found I could move the nut with my fingers while rocking the tire back and forth. This is supposed to be torgued to 230nm! How do I now torgue this thing while it is on the bike? Is this reasonable or do I need to take it all apart? Kind of scary that I can turn it with my fingers even though only a couple threads are not screwed in.

Take a look at a thread I started last month.

http://www.bmwlt.com/forums/showthread.php?t=6933

Like those pictures. Yea, I thought it was scary too.

My ball joint came loose. Dealer says that that sort of thing happens.
I check that part now.


Lewis

[parishollow]

I will replace that piece after I get it back from a clutch replacement.

[PeteM]

Sometimes when you order a lower bridge, it comes with a ball joint installed already. Usually not. It keeps you guessing. There is a fixture to hold the bridge when torqueing the ball joint, but I think it can be done in a vise using soft jaws. 230 nm is pretty high, so it needs to be secure. Resist the impulse to use locktite here, or plan on buying a new bridge when the ball joint wears out. This is the second occurence of this problem reported in about a month. Interesting.
BMW suggests the use of loctite with good reason. To remove the addition of heat allows removal.
PeteM aka murray

[mobygrape]

BMW does not indicate the use of locktite on the ball joint to bridge connection. Quite the opposite. They say to use anti-sieze.