New ride from Bainbridge Island WA

[bluekbike]

Hi all,
Just got a new-to-me '94 K1100RS recently. I had a '81 R1100RS in the dim and distant past and had to sell it (much to my chagrin as the then wife did not go for the sidecar option I proposed) when I had kids. Well, back from a three month road trip not on the bike and getting to grips with the RS....this new brick is considerably more complicated than my '81 but I am hoping to be able to fix everything it needs with some help from everyone on this site.
Took it for a spin and it rides so nicely, very maneuverable despite it's bulk. Motor is sweet but electrics are the problem....fan is kaputt and after installing new bulbs in the tail, both tail and stop lights seem to want to stay on all the time. Dash red light goes off after pressing both hand and foot brake controls but that perky stop lamp still stays on. Is it possible for a BMU to fail in this way? I would love to put some serious miles on this but I'm not going anywhere until those light issues are fixed. Looks like it is Selsun Blue color and has 61000 miles, has not been ridden for at least 4 years.

[frankenduck]

There's probably a decal under the seat with 690 on it. The color is Seiden Blau - Silk Blue.

Diagnose BMU:



Pull the BMU from the socket.

With the bike turned on, running or not, shorting socket terminal E1 (front brake switch) to 54A should illuminate the brake light when the front brake lever is pulled. It should go out with the brake lever released.

Same for terminal E2 which is the rear brake switch.


Selsun Blue is shampoo.

[stokester]

Like that color!

[Laitch]

. . . after installing new bulbs in the tail, both tail and stop lights seem to want to stay on all the time.

The old bulbs were functioning correctly?

[bluekbike]

No, they were not

[bluekbike]

Oh....the PUNishment !!!
Thank you for the advice Frankenduck. Soon as I stop laughing (at myself), I will take a shower, wash my hair and get to diagnosing. The previous post was for Laitch about the original bulbs, I'm not sure how to include the quote bit in the reply yet.

[Laitch]

The previous post was for Laitch about the original bulbs, . . .

One, or both, brake light switches activated by either the hand lever or foot pedal could be seized in the On position. That might not show as a fault to the BMU; to the BMU, a lit bulb is a good bulb. I'd check those switches first.

[bluekbike]

One, or both, brake light switches activated by either the hand lever or foot pedal could be seized in the On position. That might not show as a fault to the BMU; to the BMU, a lit bulb is a good bulb. I'd check those switches first.

Well, Laitch nailed it. Front brake switch is u/s. tried DeoxIT, left it overnight and no good. I will have to get a new one. Interesting enough I failed to find any information about the switch on my Clymer manual or the Repair Manual but I may have missed it. Got the scoop off the Tube, but there again...nothing on the K models, only on the R models which was a bit more complicated a procedure than on the K. All I had to do was remove one screw and its cover and there it was. That's not to say the BMU hasn't also failed but I will wait and see. In the meantime a accessed the rear brake switch and gave that some love.
Thank you Laitch and Frankenduck.

[The Mighty Gryphon]

The front brake switch is in a tough spot where it gets doused with water and brake fluid. 

Fortunately, it is a standard NC(normally closed) microswitch.  I have replaced several of them with units I get on Ebay. 

[Laitch]

Well, Laitch nailed it. Front brake switch is u/s.

It's too early to start the party, bluebike, but you could start collecting coupons for snacks and paper plates. Regardless of the outcome, those can come in handy for birthdays.

[frankenduck]

Alternate K1100 front brake switches:

http://www.k11og.org/forum/viewtopic.php?t=13433

[The Mighty Gryphon]

Alternate K1100 front brake switches:

http://www.k11og.org/forum/viewtopic.php?t=13433

Yep, that's the one I used.

[milq]

I'm a member of a few different forums as my motorcycling (and boots and watches) interest are all over the board. This remains the single best for people who are willing to help out with a part number, advice, or just a gentle kick in the ribs.