Rear running light / break light? LED

[ChristSFP]

So in my ongoing rebuild I really would like LED tail light for break and running light..

I understand that the K has separate bulbs for break and running lights but how do I make it work with my LED break/running light?
Is there a easy way? In a worst case scenario I can actually use the integrated running light in my turn signals, that I seemed to fix the other night.. but the break light would be nice to have working separate ;)

I have seen such a nice build from this bike so what I´m striving for is something like this.


 

[ChristSFP]

Ok.. So now turnsignals (LED) works.. And I can have runninglight in the taillight (LED).. But not the breaklight?  Or I can have the breaklight but then it is constant on and from the same pin as where the running light connect...(the bottom one, next to ground)? Any tips?

[Freelancer]

My best tip?

  Run a separate light for the brake. The led marker/brake combos usually don't have enough variation in intensity to be safe.
  What I mean is that while the marker will be Hella bright there won't be much difference when the brake part activates.

The safest set up is a gentle marker light with a separate brake that is scary bright. This way the cages can actually see when you are on your brakes.

Seriously, you want your brake led's to be bright enough to get the attention of Suzie soccer mom when she has her nose buried in here smartphone.

Btw, it's not often that I like kafe K's. Most don't get the seat line right. You have done an excellent job, I salute you.

With Respect,
Freelancer

[ChristSFP]

Thanks Freelancer,

The bike above is not mine so I can't claim any credit for that build, however it stands model for what I´m doing.

My problem is that I can't get the break light to turn on even with separate lights..? So the pin in the original cables in the back only seem to work with LED in the lower socket of the two rear light pins.

So the setup is as follow in the rear.

Turn signals with integrated break light

plus

Separate taillight (same as the project posted above) (that has both break and running light function, however Im only planing to use running light)

[rbm]

Can you post the schematic for the taillight unit you are attempting to get working?  Is it a generic aftermarket taillight meant for a variety of motorcycles with differently designed electrics?  Which company builds it?

[ChristSFP]

Basic schematics of a generic aftermarket taillight / turn signal.

LED Taillight. http://www.wrenchmonkees.com/rear-light-bates-red-lens.html

Red - Break light
Yellow - Running light
Black - Ground

LED Turnsignal (back) (front is just yellow / black and was easy enough after the flasher mod)
Red - Break light
Yellow - Turn signal
Black - Ground

So my thought is using the tail light as running light only and the turn signal integrated light as break light (or the other way around.. can't make up my mind.. but it is just a esthetic standpoint.. if anything works better, I´ll gladly work in that direction)

[rbm]

I'd agree with Freelancer.  You're going with two distinct light housings on the fender, if I understand your intent correctly.  If it were my build, I'd mount the Wrench Monkey taillight so it is physically higher up than the signal / running light assembly.  I'd wire the brake circuit into the taillight brake and running lights together to get maximum brightness.  I'd wire the turn signals as standard and use the brake light in the integrated unit as the running light.  This is visually safer and grabs the driver's attention when you apply the brakes.

By the way, how do you get left and right indications on a unit with only one wire for turn signal?  How does the unit know the difference between left and right?  Maybe the reason the brake light doesn't work properly on the integrated signal unit is because these's some fancy electronics hidden under the covers.  Have you opened the unit to check?

[ChristSFP]

Ahh no, to explain, the turn signals in the rear are two separate min LED turn signals with integrated brakelight (or running light, whichever you want but unfortunately not both).

So from each turn signal I have Red, Yellow and Black wire. All black to BMW brown and the yellow are separate on BMW original so I just connect to the corrects side of the bike =) Pretty straight forward.. that is why the brake issue bothers me..

So below is a picture from last night, all set up as quick switches to make it easy to change until I find a solution that works.

1. Turnsignal
2. Turnsignal
3. Ground from all LED (Turnsignals and tailight)
4. Brakelight (before solved, this pin gave no power.. see below for solution)
5. Running light from the bobber tail light


The yellow wire that is unconnected in the picture is running light on the bobber tail light.. somewhat misleading when the turn signals yellow represent the yellow light ;)
Also the red wires on the top of the pictures are the running light that is unconnected from the turn signals.. so turn signals in the picture is only.. well turn signals..

[ChristSFP]

Thanks for all the tips guys, so I put down some time tonight and changed back to stock lights.. And It did´t work.. So I took a steep back.

3 possible things that solved the situation.

1. The top fuse was out, changed it to a new one.
2. Sidestand was down.. this.. "embarrassing enough" could be a highly suspected cause.
3. Battery connection was bad, cleaned and screwed it in place again.

So now everything works!

So to summerise how to fix.

- LED turn signals front and back.
- LED break and running lights.

Easy.
1. Do the previous mention mod to the flasher relay, about 10 min work effort to cut the connection in the relay.
2. Install turn signals just the same as you would connect the OEM, no resistors needed!
3. Install a LED source with separate lights OR like in my case. Use turn signals with integrated break OR running lights plus a separate LED rear light.

[rbm]

Ah, glad to see all is fixed now.  It was nice you cleared up my confusion about your turn signal lights.

How about using the running light in the Wrench Monkey tail unit as a running light and wire all the brake LEDs in both the Wrench Monkey tail unit and the signal lights to the brake circuit.  That way, when you apply the brakes, the back end of the bike lights up with a triangle of red light.  But normally, all drivers would see would be the small round running light on the back of the fender.

[ChristSFP]

Yes that would be a nice solution.. Yesterday a new idea emerged.. so now I´ve order a LED strip to integrate in the tail section (I´ve used similar solutions before in projects)...

See which solution looks the part.. I´m running a bates headlight also so might wind up using the bobber tail light in the end.. just need to test this out first ;)