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Headlight Bulb Remove and Replace

bobr9

143439
1999 R1100RT

Planning on doing a bunch of work on the bike this weekend, including a headlight bulb replacement and addition of the EasternBeaver relay harness to power the light directly from the battery via relay.

Am planning on removing left and right side tupperware, but no more. Have read a few posts on bulb replacement, but still not sure I get the mental picture on how the metal clip that holds the bulb in place is configured. Have read a bunch of posts where the clip was broken because it was pulled or turned incorrectly before releasing it properly. Maybe with the left and right tupperware off I will have an open view where I can see what I am doing, but in case I don't I was wondering if anyone has a picture or drawing of what the clip arrangement looks like on this bike so if I have to do it "Blind" I'll have a decent shot at not screwing it up trying to get the bulb out. Thanks...Bob
 
The owner's manual on my K1300S has several good pictures of changing the bulbs.
Check to see if your manual has similar instructions and pictures.

This picture may help.
 

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The owner's manual on my K1300S has several good pictures of changing the bulbs.
Check to see if your manual has similar instructions and pictures.

This picture may help.

Those are great pictures. I could not find a similar description in my manual. If I can establish that the spring clip is of similar design on the RT then I think I am set. Thanks again...
 
Those are great pictures. I could not find a similar description in my manual. If I can establish that the spring clip is of similar design on the RT then I think I am set. Thanks again...

It's a similar design on about every vehicle made in Germany since maybe the 1970s.
 
I've replaced the headlight bulb on my K and R without removing the faring. Turn the handlebars to the far left and get your arm past the handlebars and your fingers on that clip. One of the few mechanical tasks where I am competent. :blah
 
I've replaced the headlight bulb on my K and R without removing the faring. Turn the handlebars to the far left and get your arm past the handlebars and your fingers on that clip. One of the few mechanical tasks where I am competent. :blah

Any difference if you turn left or right? I believe most of the posts I have seen on this say to turn right. Thanks
 
Any difference if you turn left or right? I believe most of the posts I have seen on this say to turn right. Thanks

I can't remember right or left, but you'll find out soon enough. As I recall, there is a rubber boot that goes over the back of the bulb. I believe that I install the boot and the wiring connector at the same time; makes it easier for me.

The first time I changed a bulb, it did take a while. Been easy after the first time.
 
Mechanically, I know enough to be dangerous and I was able to do mine without taking off the plastics too. Cover pops right off (almost too easy) and then it's tight back there if you have big hands to get those little wire clips on and off but bulbs slip right out. Be sure not to touch the bulb with your fingers as oil from your skin can cause those things to burst when heated up. Wipe them good with a clean rag before install. If you got big hands...find you a kid and pay him $5 to do it...you'll both walk away happy. :clap
 
The black rubber cover sort of peels back if that makes sense. You need to get it folded back and out of the way somewhat so you can get at the clip.
 
1998 r1100rt

Removing the left side won't help get to the bulb but probably provides access for hiding the kit.

There are three blades on the connector. Wiggle that off. The blades on the back of the bulb poke through the boot.
On the left and right edges of the boot are tabs you can grab to pull it off the back of the enclosure.
You may need two hands in there to get it back on but don't think about that right now.

The bale that holds the bulb in seems tougher than the rest of the materials around it... so shine a flashlight in there.
As shown on the K pictures in a previous response the bale has two round "handles" - squeeze them together to get them past the hooks.

The bulb will probably fall out. The shape of the metal part of the bulb is such that it won't go back in the wrong way.

Now. As to the relay kit. How big a bulb are you going to put in there?
There is no benefit to relays and big wires if you are going to stick with the OEM 55W bulb.

I have not done the conversion but I have studied it.
I have a spreadsheet that I think shows the benefits to be had by adding relays.

Let me know if you are interested.

Basically it shows that with stock wiring, replacing the 55/60 OEM bulb with a Philips Xtreme 80/100 will mean the Xtreme will only be producing 90% of its intended brightness. Of course that is still brighter than the OEM bulb. On the other hand the missing 10% of the energy is going into heating the wires.

Once you have solved the problem of brightness, the next issue is heat build-up in the glass enclosure.
I have heard of problems with shattering the lens, etc. from too much heat but they are lore, 3rd hand at best.

More modern vehicles solve the two problems by running two smaller headlights, say 2 x 25/35.
More light, less heat, and redundancy.
 
The blades on the back of the bulb poke through the boot.
On the left and right edges of the boot are tabs you can grab to pull it off the back of the enclosure.

Now. As to the relay kit. How big a bulb are you going to put in there?
There is no benefit to relays and big wires if you are going to stick with the OEM 55W bulb.

See the attached picture. So what everyone is telling me, I think, is that the round plastic cover with the two tabs that surrounds the bulb and the rubber boot does not need to be removed? Just checking as my arrangement is somewhat different than the ones posted for the K1300. I'm having trouble seeing how just peeling back the rubber boot will provide access to the metal clip.

On the other issue, I am going back with a Philips 55/60, so no I am not upgrading to the higher intensity bulb. I did this conversion on my K100 and it seemed to make a difference in the output just using the stock bulb, but maybe it was my wishful thinking that it would. I already have the kit, so I am going to do it anyway, but maybe I will look at upgrading to the higher intensity bulb at the next change. I would be interested in seeing your research though and am very appreciative of you sharing it. Thanks again...
 

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See the attached picture. So what everyone is telling me, I think, is that the round plastic cover with the two tabs that surrounds the bulb and the rubber boot does not need to be removed? Just checking as my arrangement is somewhat different than the ones posted for the K1300. I'm having trouble seeing how just peeling back the rubber boot will provide access to the metal clip.

On the other issue, I am going back with a Philips 55/60, so no I am not upgrading to the higher intensity bulb. I did this conversion on my K100 and it seemed to make a difference in the output just using the stock bulb, but maybe it was my wishful thinking that it would. I already have the kit, so I am going to do it anyway, but maybe I will look at upgrading to the higher intensity bulb at the next change. I would be interested in seeing your research though and am very appreciative of you sharing it. Thanks again...

I need to remove the rubber boot to get to the clip. Once the new bulb is locked into place, for me, it is easier to run the connector through the boot, make the connection to the bulb's three prongs and then pull the boot over the outside circumference. First attempt (putting the rubber boot on before attaching the connector) took forever and subsequent bulb changes run about 5 minutes.
 
I need to remove the rubber boot to get to the clip. Once the new bulb is locked into place, for me, it is easier to run the connector through the boot, make the connection to the bulb's three prongs and then pull the boot over the outside circumference. First attempt (putting the rubber boot on before attaching the connector) took forever and subsequent bulb changes run about 5 minutes.

I just discovered the source of my confusion; nothing like actually doing the job. I thought the rubber boot over the connector was a separate piece from the large round cover, which I thought was plastic. Turns out it is just one big rubber boot. Thanks for your help...
 
Justify relays.

I already have the kit, so I am going to do it anyway, but maybe I will look at upgrading to the higher intensity bulb at the next change. I would be interested in seeing your research though and am very appreciative of you sharing it. Thanks again...

Yeah, I probably would too.

I created this spreadsheet to illustrate the benefits to be had by upgrading the headlight wiring in my BMW R1100RT.
This motorcycle has a single standard 55/60 H4 headlight bulb, with 18 gauge wiring. The current to power the bulb goes through the low/high switch on the left-hand handlebar. The total run length of the wire is probably 6 or 8 feet.

There are two parts to the sheet.
The main part to the left shows various intermediate values and formulas leading to the %Brightness column.
The light blue box is a shortcut version displaying brightness for a given wire size for different wattage bulbs.

When engineers design wiring they usually try to keep the voltage drop (and thus the power loss) to less than 5%. As you can see the stock wiring falls well below this at 2% drop with the stock bulb on high beam.

Because of the way light bulbs work, a small voltage drop can result in a significant loss in light output.

With stock wiring the stock bulb is running at about 99% of its rated brightness on high beam. This seems acceptable.

But over in the blue box, watch what happens when we try to get more light output by moving to a Philips X-treme 80/100 H4 bulb.

The X-treme claims to produce 80% more light than a standard bulb. However the increased current flow increases the voltage drop and thus diminishes the light output of the bulb. The new bulb will still be noticeably brighter than stock, but instead of being 80% brighter, it will be (92% of 180) - 100, or about 65% brighter than stock.

Moving to 12 gauge wiring and relays brings the light output of the hotter bulb back up to the where it should be.

Also keep in mind that power isn't really lost, it always goes somewhere. Any power that isn't getting to the light bulb is being used to heat up the wires.

P.S.
Instead of buying and installing a kit, I run a Sylvania Silverstar bulb. It is still 55/60W, but is quite a bit brighter and whiter than the stock bulb. It is NOT 80% brighter, more like 25%. And if you do this you will want to carry a spare Silverstar, and possibly a spare OEM el cheapo bulb. Why? The stock bulb is extremely tough. A conventional H4 bulb might last 10 years or 20 years, but you can count on the Silverstar burning out within a year or two. Sylvania does not boast about the short life expectancy of course but they also don't make it any big secret. I don't know if the X-treme has a short life expectancy as well - I would say probably.
There's no magic there. Incandescent bulbs make light by heating a piece of wire to incandescence, which is, dang hot. The hotter that wire gets, the more light comes away from it. The hotter the wire gets, the shorter the amount of time it will survive. The Silverstar uses a time-honored trick of being "designed" for a lower voltage than it will actually be run at. Before we had fluorescent bulb replacements, you could find "140V" light bulbs for the house, which would run cooler and last longer when run at the actual house voltage of 120V.
 

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