R1100RT Engine Support Pin Torque

[BMUU]

Several months ago, I had the clutch replaced on my R1100RT. When I recently removed the Tupperware to perform some unrelated maintenance, I was shocked to find a host of problems, some just sloppy workmanship and others more serious.

 

The most serious problem I found was the two 10mm nuts, securing the front engine support pin, were so loose that one was about to fall off. I’ve corrected all of the other problems (there were over a dozen, some serious, some not), but I’ve yet to tighten the support pin, because I have no idea what the correct torque value is. I’ve searched my various shop manuals, as well as the internet without any success. I could just tighten it to a standard 30 – 35 nm, but because it’s part of the engine support structure, I suspect it’s a high-grade bolt and needs to be torqued to a fairly high level. In any case, I don’t want to guess at it.

 

The pin in question is 10mm x 271mm threaded on both ends. It is BMW part number, 46 51 2 314 568 and is labeled #3 in the attached diagram.

 

I’m hoping that one of you tech geniuses out there can give me the proper torque value for this pin, so I can put the Tupperware back on and be done with this project. Who knows, someday it may even stop snowing so I can go for a ride!

 

Thanks!

 

 

[dirtrider]

Afternoon BMUU

 

You just had to ask?----

 

So I will confuse you with nothing reliable.

 

Personally, I just tighten that 10mm threaded stud (pin if you will) to "tight enough that it won't come loose but not so tight as to stretch it, strip it, or damage the engine case". BUT-- I have been in the auto engineering area of a major auto company for well over 40 years so one thing I have is a very good gut feel for how tight a faster should be.

 

So I just looked it up (well tried anyhow) & the bad news is I have conflicting data in my manuals. To make it even worse it looks like different models spec different torque specs.

 

SO--

 

Here is what I don't have for you.

 

That threaded stud (pin) uses 10.9 10mm nuts so that "probably" means the stud itself is a 10.9 or thereabouts. The standard unplated torque on a 10.9 10x1.50 bolt or stud is about 47 nm.

 

I found 2 places in one of my old manuals that show (I think) those nuts torque to 47 nm so that seems to fit.

 

I also found reference to 58 nm in both an 1150 manual & a 1100R & GS manual. (again nothing concrete).

 

Hopefully someone has something solid for you here.

 

If not, then my recommendation is to (first) call your BMW dealer & hope they just don't take a wild guess at it (my guess is most use my no-torque feels right method)

 

Barring that then I would suggest you initially torque it to 47 nm (that should be plenty safe). Once at 47 nm try tightening one side nut to just a bit more & see how it feels. Even at 47 nm (if that is the spec) you should be plenty safe into the low 50nm range.

 

[Edgar]

X Tightening torque:

Leading link at ball joint

(clean thread + Loctite 2701)...................... 130 Nm

Fork bridge to frame

(clean thread + Loctite 243)........................ 130 Nm

Frame to engine ........................................... 82 Nm

Struts to frame (10.9 screw) ......................... 58 Nm

Struts to engine............................................ 58 Nm

Fairing support bracket to frame .................. 20 Nm

 

Looks like it's 58 Nm / 43 Ft Lbs