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Color of threadlock for rear brake disc?

Okay, I give up. I have tried to use the search function but can't seem to find some information that I am sure has been covered before. I am changing the rear brake disc on a R1100. All the manuals call for Loctite 273 when the disc is bolted to the final drive. Anyone know what color this stuff is? My local parts store only carries Permatex, which I understand is Loctite's comsumer brand. Is there a conversion? I have some 242, but I gather that is not strong enough. The threads now seem to show a grey material as threadlocker. Probably the original. If I use red, will I ever get the disc off again if need be? Thanks.

Just as an aside, is it just my computer, or is the little white box where you type in what you want to search for in the forum, now obscured by the word "Forum" since they "improved" the site a short while back? So now you can't see what you are typing. Does that make any sense to anyone? (Make a note to self: call BMWOA headquarters and have them actually open their own website. Be told, "You're the first person to tell us that. But you know, you're right..... Joe, call the programmer back in...." )
 
273 is high strength red threadlocker.
FWIW, the forum displays fine on my pc's or Macs including a clear search box. Any chance you've on a very small or truncated screen or can move to the right?
 
FWIW the first time I took the rear disc off of the final drive on my 1100rt I noticed the threadlocker on the capscrews was BLUE.....and so thats what I use.
No issues.....the threadlocker assists holding the capscrews in plce after tourqing.
 
FWIW the first time I took the rear disc off of the final drive on my 1100rt I noticed the threadlocker on the capscrews was BLUE.....and so thats what I use.
No issues.....the threadlocker assists holding the capscrews in plce after tourqing.

Blue it is :thumb
 
Just as an aside, is it just my computer, or is the little white box where you type in what you want to search for in the forum, now obscured by the word "Forum" since they "improved" the site a short while back? So now you can't see what you are typing. Does that make any sense to anyone? )

Since the update, the same thing happens on my small netbook I use when travelling.
I think the fix is on the 2015 To Do List.
 
Just as an aside, is it just my computer, or is the little white box where you type in what you want to search for in the forum, now obscured by the word "Forum" since they "improved" the site a short while back?

That problem is a function of the width of the forum header.

Hold the control key down and depress the dash key one or two times. That shrinks the display so the full header fits across the page. You can then type in the search box. But the text size on my little 11.6" screen is then a bit hard to read.
 
Back to threadlocker. Look at the system and the fasteners. Some bikes have the disk fastened directly to the final drive hub. Some have the disk bolted directly to the wheel. I think (but am not positive) that the early R1100RT bikes have the disk fastened to the final drive with two itty bitty flat head capscrews like on the R1100RS bikes.

On bikes where the disk bolts to the wheel I would use high strength thread locker.

But, where the disk is fastened to the final drive crownwheel hub, all four big stout wheel bolts pass through the disk and clamp it and the wheel stoutly to the final drive hub with 77 ft. lbs. of torque. With the wheel on, that disk can't go anywhere. Those little capscrews just keep the disk from falling off and clattering to the floor when the wheel is removed.

Thus, as far as I'm concerned medium strength (blue) or even low strength (purple) thread locker is more than sufficient where the disk fastens directly to the hub. In this situation the major benefit from the thread locker is to serve to impede corrosion on the threads.
 
Good points on the way the disc is held on when it is bolted to the final drive, as mine is. Thanks for the input, Paul. I actually went to my local Autozone and read the back of a package of the high strength, red Permatex threadlock, number 271, I believe. It said that you needed 500 degrees of heat to break the bond to remove it. That's about four times the 130 degrees the manual says is needed to back off the screws, using a heat gun. I think we are talking about a torch for heat here. That's more than I want to put on all these parts. I will take everyone's advice and use the blue. I think that will work fine. Thanks to everyone for their help.
 
If you read the manual; then you should see that (on R1100RT) those screws are specified as "one-time" use. The new replacements come with blue thread lock on the threads from BMW. The screws are thin heads and appear to be aluminum; very easy to strip the small hex head if you don't heat them enough to break the thread locker. I would not reuse those screws but if you insist on it, don't use any thread lock at all. The wheel and the lug nuts will keep those screws in place and the lug nuts will insure that the disk is held in place.
 
If you read the manual; then you should see that (on R1100RT) those screws are specified as "one-time" use. The new replacements come with blue thread lock on the threads from BMW. The screws are thin heads and appear to be aluminum; very easy to strip the small hex head if you don't heat them enough to break the thread locker. I would not reuse those screws but if you insist on it, don't use any thread lock at all. The wheel and the lug nuts will keep those screws in place and the lug nuts will insure that the disk is held in place.

They are steel, I have always reused them with no issues. There is usually enough residual threadlock on them to not need more.
 
If you read the manual; then you should see that (on R1100RT) those screws are specified as "one-time" use. The new replacements come with blue thread lock on the threads from BMW. The screws are thin heads and appear to be aluminum; very easy to strip the small hex head if you don't heat them enough to break the thread locker. I would not reuse those screws but if you insist on it, don't use any thread lock at all. The wheel and the lug nuts will keep those screws in place and the lug nuts will insure that the disk is held in place.

On Voni's RS the capscrews are steel, but have a thin head and very shallow socket for the allen wrench. Even the steel ones strip easily. An aluminum one with thread locker would very easily strip the recess for the wrench.

I heat them with a small "pencil" type butane torch applying the heat directly to the center of the capscrew. This gets the thread locker very hot without applying a lot of heat to the surrounding area.
 
That problem is a function of the width of the forum header.

Hold the control key down and depress the dash key one or two times. That shrinks the display so the full header fits across the page. You can then type in the search box. But the text size on my little 11.6" screen is then a bit hard to read.

Dang Paul, do you know everything?! :bow
You're kinda handy to have around. No kidding.
I guessed blue but likely I would have asked Paul, I'm really not a wrench. (understatement)
"I just ride 'em I don't know what makes 'em work" ~ Oddball
 
Back to threadlocker.... all four big stout wheel bolts pass through the disk and clamp it and the wheel stoutly to the final drive hub with 77 ft. lbs. of torque...

Seems like there is no need to use any thread locker at all. You don't really even need those keeper bolts, except when the wheel is off.
 
Seems like there is no need to use any thread locker at all. You don't really even need those keeper bolts, except when the wheel is off.

From a practical standpoint this is true but using some low strength threadlocker is a good way to seal the threads and prevent corrosion. Grease would work too, but is not as permanent. The only time these need to be removed is if the disk is replaced or the final drive needs to be rebuilt, so undoing the capscrews with low or medium strength threadlocker is no big deal if you use a pencil torch.
 
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