• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

  • Beginning April 1st, and running through April 30th, there is a new 2024 BMW MOA Election discussion area within The Club section of the forum. Within this forum area is also a sticky post that provides the ground rules for participating in the Election forum area. Also, the candidates statements are provided. Please read before joining the conversation, because the rules are very specific to maintain civility.

    The Election forum is here: Election Forum

'91 K75 Replacement Bulbs

Didymus

New member
I feel a little silly even posting this, but I have an old K75 that I'm trying to get legal (not as easy as it sounds in Maryland), and I've spent hours trying to find replacement bulbs for the headlight. I finally picked up a H4 type bulb at the local auto parts place that should be fine for the big, center bulb. Though, the low beam still isn't working even with the new bulb and I don't know why yet. And, I don't even know what the other little light is for. Haynes manual calls it a "parking lamp"? The socket was empty, so I picked up a couple of bulbs with the same shape, but they're too big. Guess I should have measured the socket first, but I figured it would probably be a fairly standard bulb. Maybe I was wrong. It's a 12V 4W bulb, part #07 50 9 063 576. Do I really need to order this through a dealer? And I'd really love to find LED replacements for all of the bulbs, but that might be asking too much. Ideas?

And what about any general online resources for fixing up an old K75. I'm sure they're out there, I just don't know where to look.

Thanks in advance.
 
Last edited:
standard H4 55/60W headlight bulb.

LEDs exist for the parking lamps, as do std incandescent. not sure of the part numbers req'd. yes, all are available from most Auto Parts stores.

info here on MOA (learn to use the search function, upper right corner), as well as some possibly relevant info here- http://www.k11og.org/ , here- http://www.k-bikes.com/forums/showthread.php?t=7275 and here- http://www.i-bmw.com/showthread.php?t=43472

(ya know, it's amazing what google can find for you, if you just give it a try....)

good luck with the resurrection. pay attention to old rubber, including (especially) the fuel pump mounts inside the gas tank. they get sploogey if left to sit in gas (especially gas that is heavy with the ethanol), and sploogey mounts and fuel injectors do not get along well at all.
 
The parking lamp part number is the same as my 85 K100RT. Mine was replaced a few years ago with a bulb from NAPA (Part Number: LMP 1816) for about $2.00

At the time there was a concern about the heat from the headlamp being hard on an LED, so I went with the incandescent bulb.

Best of luck.

Monte
 
A nice thing about the parking light is when the big bulb burns out, there is still a little light in the housing. The low beam not working could be from the wrong bulb, bad bulb or a bad switch. H4 bulbs should be easy to find. I got LED's for my Ural from superbrightleds.com, they have a good selection of common bulbs (including H4) and specifications on socket sizes and fitments. Good luck with your classik K!
 
There's a high possibility that your high/low beam switch on the left handlebar cluster has gone bad- my '92 K75RT has burned up three switches in the last 6 years. Try putting a voltmeter across the bulb socket terminals and switching from high to low beam to verify the power is getting to the bulb.
Before splashing out big bucks for a brand new one check out "beemerboneyard.com" and "Re-psycle.com", they both carry used spares at a reasonable price.
Good luck,
Scoobs
 
There's a high possibility that your high/low beam switch on the left handlebar cluster has gone bad- my '92 K75RT has burned up three switches in the last 6 years. Try putting a voltmeter across the bulb socket terminals and switching from high to low beam to verify the power is getting to the bulb.
Before splashing out big bucks for a brand new one check out "beemerboneyard.com" and "Re-psycle.com", they both carry used spares at a reasonable price.
Good luck,
Scoobs

And if you do have to replace the switch, install a set of relays so the switch doesn't fail again. Eastern Beaver makes an excellent plug & play set.
The switches fail because the stock wiring is undersized for the load, the switch gets hot and the contacts melt and recede into the housing. This is a long time, well known issue.
 
I never had problems with the wires, just the contacts all tarnished and gummy to the point they would not move or conduct electricity. I took it apart and cleaned it and now it works great. Be warned - there are bunch of spring loaded pieces inside that will fly all over when you open one up, so be ready. Seems you have to do this every 20 years or so.
 
Thanks and Update

Thanks for all the replies.

In case anyone else has a similar question, that little 12V 4W bulb I was looking for is a BA9s bulb like this one:
http://www.newark.com/lux/bs249/lam...dywDsFoj|pcrid|33869889261|plid|&CMP=KNC-GPLA

There are also LED replacements available;
http://www.superbrightleds.com/cat/ba9s-ba7s/

BUT, be sure to get one where the actual bulb isn't wider than the base. Because you have to insert it into the reflector from the back, one with a large bulb like this, won't work:
http://www.sheridanmarine.com/product/incandescent-12v-5w-small-bayonet-ba9s-bulbs

You can probably pick one up at the local auto parts store, just make sure it's a 12V (or higher) 4 watt bulb with a BA9s base and it's got the narrow shape that will allow you to fit it into the headlight. As mentioned, the big bulb is a 12V 60/55W H4 bulb and is definitely available at your local auto parts store. I was not able to find a decent LED replacement for the H4 anywhere. They all seemed to have about 1/3 of the lumens of the traditional bulb and I don't want something that's less bright. If anyone knows otherwise I'd love to know about it.

So anyway, in my case it turned out that the problem was the switch. To remove it, I took off the tank by following the instructions from this guy;
https://www.youtube.com/watch?v=od4r7SoIPRo

Once the tank was off, which was actually really easy, I unplugged the switch from the rest of the wiring, BUT, it was a pain to actually get it out because the big, fat plug wouldn't fit between the frame and the headlight/instrument assembly. So after taking off the tank and unplugging the switch, I had to remove some stuff from the front of the bike too in order to get the plug out.

This was a hassle, but I was really glad that I went to the trouble so that I could work on it indoors because of the tiny parts, the jumping screws etc. Some of the bits in the switch are spring loaded and if you lose them in a parking lot or garage you're probably screwed.

I chose not to mess with the horn or signal switched because they were still working fine and I'm just trying to get this bike past inspection at this point. I carefully took apart the high/low beam switch and cleaned it with a toothbrush and some contact cleaner I picked up in the electrical section of the local mega hardware store, but it was pointless. One of the little contact "bumps"? soldering "dots"? "doodads"? was missing or maybe melted, so it didn't matter how clean the switch was, it wasn't going to work again.

So I found a used Kbike switch on ebay for $3. It was from a K1100LT, and when it arrived I found out that, even though the switch was the same, the plug was not. So I ended up cutting the wires from both switches and soldering the old plug to the new switch, putting it all back together, and everything is working right now.

Next step is to eventually look into the eastern Beaver relays to see if I can prevent this from happening again.
 
Back
Top