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stripped allen head

woody99

Member
96 R1100RT
While trying to remove one of the two allen head bolt holding on my rear brake rotor, after heating extensively with heat gun, propane torch and acetylene torch and still not being able to remove the bolt the allen head stripped . the other side came out with no heat at all? So now I have to drill it out or leave the same rotor on the bike. It looks like the 4 bolts that hold the wheel on would keep the rotor in place without any bolts. Anyone have any ideas? Thanks Woody
 
96 R1100RT
While trying to remove one of the two allen head bolt holding on my rear brake rotor, after heating extensively with heat gun, propane torch and acetylene torch and still not being able to remove the bolt the allen head stripped . the other side came out with no heat at all? So now I have to drill it out or leave the same rotor on the bike. It looks like the 4 bolts that hold the wheel on would keep the rotor in place without any bolts. Anyone have any ideas? Thanks Woody
Always easier with a picture but I will have to guess the part where the Allen head fits into stripped out? I frequently drop a nut over it and weld in the center so I can grab it again. I have also chiseled them around in a circular pattern but that's a bit iffy.
OM
 
take a next sized up torx bit and use a hammer to drive it in and form a new socket. This has never failed me.
 
take a next sized up torx bit and use a hammer to drive it in and form a new socket. This has never failed me.

Do this and try no heat. Any low level thread locker was cooked with all that heating you did before, now you are just expanding the fastener.
 
Don't know if this is applicable but it is not uncommon for a weldor to place a hex nut over a stuck fastener and plug weld it on. In addition to having a nice new hex head the heat also helps. In not as good of a welder as some so I weld a heavy flat washer on first then a nut.

Good luck
 
I'm also a fan of the welding technique. I will usually try a next size standard bit or torx bit first, but the welding trick rarely fails. Sometimes it takes multiple attempts. The washer trick can help as it will shield some of the surrounding steel. Sometimes I just take a a piece of flat stock and weld it straight to the bolt, using the flat stock as the wrench handle.
 
Those allen recesses are very shallow and BMW uses high strength thread locker at the factory. I have had good luck with heat from a pencil torch right in the center of the recess followed by using a torx bit driven into the recess. I would re-use heat again, but not a lot, because the threadlocker can reset after it has melted.
 
Woody, those screws are specified as one-time use. The heads are shallow and they are easy to strip. You are right; on the R1100RT, the wheel lugs will hold the rotor tight - those two screws are really just there to hold the rotor in place. The thread locker on those screws is overdone. Get the stripped one out any way you can (lots of good advice already given) and then get a new screw to replace it.
 
Woody, those screws are specified as one-time use. The heads are shallow and they are easy to strip. You are right; on the R1100RT, the wheel lugs will hold the rotor tight - those two screws are really just there to hold the rotor in place. The thread locker on those screws is overdone. Get the stripped one out any way you can (lots of good advice already given) and then get a new screw to replace it.

+1
 
Sounds like you are at 100% success rate too. Glad you were successful, sure beats the other choices.
 
Nice thread, I just had to bolt mine all back together with the old rotor still on there after having the same problem. I'll try the heat+torx technique, and maybe scrape some of the threadlocker off the new screws for good measure. (They're 86 cents at the dealer, by the way.)

On a side note, for the "slip a bolt over it and weld" advice -- these screws are flat-head, countersunk into the rotor carrier. Nothing to slip over, unless you drill the heads off and remove the rotor.
 
Thanks to all for the torx suggestion; I'll have to try that next time. When the head on one of my '94 RS's bolts stripped, I just drilled it out, as I was replacing the rotor anyway. Easy to grab the remaining shaft with visegrips. And yes, the retaining compound is over the top ;-).
 
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