Changing bulbs in r100rt tach and speedo

Since I have seem to have half my 88 r100rt apart already, i figure it's a good time to replace the burned out bulbs in the tach. Speedo is ok, but might as well if i'm in there anyway.

Problem is, how do I get to the bulbs? I can't figure out how to open up the instrument cluster. Anybody done this?

You have to remove the backing plates which will reveal a plastic sheet with the conductive leads on it. the blubs are in the little plastic housings that are in the slots with the leads. You have to gently rock the plastic housings out so as to not destroy the plastic leads on it. Once out, the bulbs are easy to replace. The hard part is to not damage those little metal leads on the palstic sheet. Its a lot easier for me to show rather than to explain but once the backing plates are off you can see what I am talking about.

Check out these pics from the Airheads site on fixing odometers. Pic #3 shows the instrument and indicator bulbs exposed. Should give you a pretty good idea on how to get at them.

http://www.airheads.org/content/view/160/98/

but first...

good advice for what to do once i'm in there, but I'm stuck at how to start. How can I even get the instruments off? I can't see anything but the speedo cable and a wire leading to the back of the instruments. What nuts, bolts, screws do I need to remove and how do I get to them?

It's not clear to me what bulbs you're talking about replacing. If it's the idiot lights down the center of the instrument pod, then the previous link shows you how to get to those bulbs. But if the bulbs are the ones that actually light the dials on the tach and speedo, they're buried deeper. I looked at the previous link and don't really see them displayed. Possibly by the time you got to photo 7, you might be able to see some kind of wire or bulb that needs to be changed. Now that I look at the fiche, maybe those "arms" that extend out from the center strip contain the lights for the two instruments:

http://www.realoem.com/bmw/showparts.do?model=0469&mospid=47845&btnr=62_0235&hg=62&fg=05

The instrument pod should be held onto a bracket that comes off the top steering stem brace. My /7 has three 10mm bolts that are loosened. After loosening the knurled nut for the speedo cable, a small screw holds a molded plug on the back. After the plug is carefully worked off, the pod comes free. The 10mm nuts are #18 in the above link.

The plug may the big square blocky thing on harness #2:

http://www.realoem.com/bmw/showparts.do?model=0469&mospid=47845&btnr=61_0242&hg=61&fg=05

Be sure and look at the pins on this molded plug. If it's never been off before, there may be a fair amount of corrosion on the pins and in the plug. Use some dielectric lubes or cleaners to clean things up.

Once the pod is off, you can proceed like the previous link shows.

going for it

Kurt,

thanks for the referenced diagrams and advice. Mine's a pain because access is complicated by a panel in front of the instuments. It holds to rocker switches, one of which is for the heated grips. I guess I'll have to remove that panel first before I can get close to the other stuff.

oh,

BTW, it is the tachometer light bulb I'm replacing. I figured I'd do the speedo too since I'm in there

3moskvichi said:

Kurt,

thanks for the referenced diagrams and advice. Mine's a pain because access is complicated by a panel in front of the instuments. It holds to rocker switches, one of which is for the heated grips. I guess I'll have to remove that panel first before I can get close to the other stuff.

Click to expand...

You may not have to remove that panel that holds the rocker switches. It may make things a bit easier if you do, but first see if you can get a 10mm wrench (I think it is 10mm) on those three bolts that hold the cluster in place. All you have to do is loosen them, not remove them completely. Then the cluster can be pulled straight up off its mount. I think the mount is slotted. Thus, you do not need to remove the bolts.

fracture said:

You may not have to remove that panel that holds the rocker switches. It may make things a bit easier if you do, but first see if you can get a 10mm wrench (I think it is 10mm) on those three bolts that hold the cluster in place. All you have to do is loosen them, not remove them completely. Then the cluster can be pulled straight up off its mount. I think the mount is slotted. Thus, you do not need to remove the bolts.

Click to expand...

Going through the same thing myself. In fact my local instrument repair guys are going over my speedo mechanism which is prone to gear slippage and related problems. Good advice so far. Loosen those 3 10mm under the cluster and then slide the cluster toward you (as if you were sitting on the bike) and then unscrew the speedo cable by hand or start it by some judicious use of channelocks. Then flip the cluster over to gain access to the backside. On the wire harness, use a phillips to remove 1 (lower?) screw and the harness should pull straight out with maybe a little twisting. Good time to clean the connections. Once the cluster is out of the bike you can remove all the other phillips screws on your bench to get at all the bulbs. One thing I discovered was that one of the contacts for my hi-beam bulb had folded up underneath the flexible circuit board. I had thought it was a bad bulb. Flipped it back out and scraped it with an Exacto blade and problem solved. Good luck.

Speedo/Tach Caution . . .

I replaced my lights in the pod. It was the first time they had been apart since new. (17 yrs) There was no lubrication on aluminum pins that were inserted in s/s recepticles. Get my drift? Destroyed aluminum pins and big black rubber plug.
Then learned that to repair said plug required a new wiring harness. $330. and a few hours later properly lubricated wiring harness installed.
Expensive but excellent learning experience.
BTW I bought LED bulbs at autolumination.com Not cheap but look great at night.
Campbell Tellman II
'93 R100RT