Tail Light Assembly

[RobT]

I was riding my 2000 R1100RT home up the Sacramento Delta Saturday, stopped at winery to pick up a bottle, and after dismounting noticed that my entire tail light/indicator assemply was hanging by the wires!!

 

Rather than mess with it on the road and break an expensive (is there any other kind?) BMW part, I strapped it back in place and got home uneventfully.

 

I saw the screws (bolts?) leading from the assembly to the tail, and saw the holes into which they fit. My concern was that it appears I have to take the assembly cover off to access the screw/bolt heads.

 

Question 1: Is there a trick or "best" way to get the cover off without cracking/chipping it? Or is it a matter of just prying it off?

 

Question 2: I had my 24,000 mile service done by a dealer a couple weeks ago, but put over 700 miles on the bike prior to this occurring. Is this something that happened due to shoddy reinstallation of the assembly (assuming it had to be removed during the service) or is there another cause?

 

Question 3: Ever hear of this happening before?

 

I appreciate any information you can provide.

[Ken H.]

Well your description of what you are seeing confuses me a bit, from what is typical, but, if you look at the taillight ass'y, the red and yellow piece, does it have to threaded metal studs sticking out of it?

 

Presuming yes, then from under the pillion seat, back in the rear section of the bike you will likely still find the two thumb screw nuts that thread onto the studs and fasten the taillight to the bike.

 

Them coming loose this way is well known. Some people put a rubber band between them or various other ideas to keep them tight. Periodically checking them seems to be the best idea.

[Alan D]

I think I understand what you are saying.

Remove the rear seat and I think you will have access to the assembly and you can install new nuts on the two bolts that hold the assembly on. (The nuts may be laying in the tail section)

Good luck

[RobT]

Got it. Thanks much. I'll check tonight and let you know.

 

This is an Invaluable Board!

[RobT]

Yep, that was it. Both plastic screw caps were just sitting in there. Put them back, tested lights and we are good to go for another weekend ride. And, currently, the weather for NorCal is looking not too cold, not too hot, but just right!

 

Thank you much!

[FrankT]

Robert,

My tailight assembly came off and was dangling twice before I finally decided to replace the stock plastic thumb screws with locknuts . I did have to add a socket and extension to my toolkit for possible road service .

[ratfink]

I replaced the plastic thumbwheel nuts on my bike with metal wingnuts and a little blue loctite. No problems since. Don't over torque as you could dislodge the stud from the plastic base.

[Francis]

I too have had this happen. The plastic nuts back off and your light unit hangs by the wires. Follow the above instructions and all should be well.

 

Francis

[Green RT]

Is this one more thing to worry about. I'm at 80,000 miles and haven't even thought about this. I still have HES rewiring on my to do list and now I have to remember to tighten my tail light bolts. Don't even mention a spline lube. How am I ever going to find time to ride with all this preventative maintenance backing up on me.

[myshkin]

I have had just the opposite problem. When I needed to replace the bulb I couldn't get the dang nuts off.

[Jim VonBaden]

I too have had this happen. The plastic nuts back off and your light unit hangs by the wires. Follow the above instructions and all should be well.

 

Francis

 

Or, tighten them back on, and use a couple rubberbands wrapped from one to the other against the loosening side. Hard to describe, but easy to figure out.

 

This is an old remedy that works just fine.

 

Jim

[ESokoloff]

I have had just the opposite problem. When I needed to replace the bulb I couldn't get the dang nuts off.

 

Use a socket.

I presume a 12 point but I don't know what size.

 

Don't over tighten.

[Laura]

I too have had this happen. The plastic nuts back off and your light unit hangs by the wires. Follow the above instructions and all should be well.

 

Francis

 

Or, tighten them back on, and use a couple rubberbands wrapped from one to the other against the loosening side. Hard to describe, but easy to figure out.

 

This is an old remedy that works just fine.

 

Jim

 

Agreed, this rubberband method works well. You still have to check it once in a while as the rubberbands dry out and break after a while.

[powerman]

I seems there maybe some washers missing for the studs/nuts

i was installing the gizmo mills rear bulb upgrade, i need acouple of new seals for the lamps themselves. i went to max's BMW parts web site and it shows in addition to the two nuts there are two washers (item 6 on the diagram), these washers probably provide some resisance to the vibe and allow a little give so the nuts don't back out, not sure if the washers go in the studs before the light is installed(light seems to have a rescess) or after like a lock washer. another cost saving measure by eliminating 15 cents. FWIW i have also found mine hanging from the wires.