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Hey everyone.

New to the board and this place is great. Lots of good info and input from all.

I was wondering if you all could confirm bulbs for me. Trying to consolidate all the info in multiple posts and get current info.
Front indicators Bulb type 921 (confirmed by Pirate)

Rear Tail?

Rear Indicators?

Also Where is the best place(s) the LEDs for clear lenses for indicators and tail. Price/shipping/support.

Thanks
Brad

05 k1200s
 

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I was wondering also if anyone who has put in LED bulbs for the turn signals has encountered error messages showing up in their dashboard LCD indicating that the bulbs are out? Or even rapid flashing because of the lower power resistance of these LED bulbs? Any solutions to that?
 

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atomic80 said:
I was wondering also if anyone who has put in LED bulbs for the turn signals has encountered error messages showing up in their dashboard LCD indicating that the bulbs are out? Or even rapid flashing because of the lower power resistance of these LED bulbs? Any solutions to that?
I think you are a bit confused with statements like LEDs have "lower power resistance" (whatever that means). In fact, the equivalent DC resistance of an LED (with its series current limiting resistor) is much HIGHER than an equivalent tungsten lamp. That is why it draws less current.

The problem here is that LEDs consume less current than tungsten bulbs of the same brightness. The bike's monitoring system is EXPECTING to see the current draw of a tungsten lamp, and if it sees significantly less, it thinks the bulb is burned out and generates a warning.

The solution is fairly obvious. You need to wire in a dummy resistor that consumes the "missing" current in parallel to the LED lamp. The problem here is that this resistor will generate about 10 to 20 Watts of heat (the same as the old bulb did), and may need to be heat-sunk to dissipate the heat (rather inconvenient on a bike).

All this is hardly worth the effort since LED turn signals don't work any better than regular bulbs and furthermore tend to be too directional. OK, they are a cool gimmick, but so are those big (useless) spoilers on boy-racer cars!

Bob.
 

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I'm aware of the resistance issue which is why I asked if anyone had found a solution to that issue. The LED brake lights work VERY well for me.
 

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I have to disagree with you Wilson. The LED directional light panels, the ones from Nippy Normans, are WAY brighter than incandescent bulbs, they are also much more noticable. And the LED Brake! light.. that thing is amazingly, bright and attention grabbing. But everyone is entitled to an opinion, I'm just basing mine on experience with these products on the S :)
 

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Erik said:
I have to disagree with you Wilson. The LED directional light panels, the ones from Nippy Normans, are WAY brighter than incandescent bulbs, they are also much more noticable. And the LED Brake! light.. that thing is amazingly, bright and attention grabbing. But everyone is entitled to an opinion, I'm just basing mine on experience with these products on the S :)
Erik, do you get any "bulb out" warnings with your set up?
 

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Nope... Both the Brake! LED's and the directional LED's have a resistors installed so as to present the correct load to the can bus system.
 

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atomic80 said:
I'm aware of the resistance issue which is why I asked if anyone had found a solution to that issue. The LED brake lights work VERY well for me.
As mentioned earlier, the solution is to add a dummy resistor so the current suppled to the LED/Resistor combo is high enough that the system "thinks" there is a real lamp installed. There is no other solution short of reprogramming the bike's monitoring system. Clearly, adding a resistor (and maybe needing to deal with the heat it generates) is by far the easier task.

Bob.
 

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I guess I'm just wondering which type of resistor should I use? I'm not sure how to figure out which one I should get. It's based on the type of wattage used by the stock bulbs, I know that much.

I just thought that Erik had somehow managed to find a retailer that sells LED turn signals with the resistors already built in.
 

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Erik said:
I have to disagree with you Wilson. The LED directional light panels, the ones from Nippy Normans, are WAY brighter than incandescent bulbs, they are also much more noticable. And the LED Brake! light.. that thing is amazingly, bright and attention grabbing. But everyone is entitled to an opinion, I'm just basing mine on experience with these products on the S :)
Certainly, I agree that looking straight-on they are brighter. The total amount of light produced by these LEDs is actually less than that produced by the standard bulb. The difference is simply that the LED's light is far more highly focused, and therefore, off-axis is much dimmer.

I suppose that with turn signals, off-axis doesn't matter as much anyway since it is only the guy behind you that you are trying to warn. I guess my main question is this: The standard turn signals are already plenty bright enough that anyone behind can easily see them. What benefit, exactly, is there to make them even brighter?

Maybe it is like daylight running lights on cars. Initially when only a few cars had them, they stood out and people therefore claimed they were much safer and more visible. But now when ALL cars have them, the latest statistics clearly show they have no effect at all in increasing safety. So it may be with LED lights. A few vehicles with them really stand out (epecially when some aftermarket ones violate the DOC limits on brightness). Eventually, when all vehicles have them, they will no longer appear to stand out.

Bob.
 

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The power output is less with LED's, BUT they are definately much brighter!

Plus as an added benefit, they virtually last forever.

Go get some Bob!
 

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Do these flash amber or red when in use? The description isn't very clear. It just says that this version has an extra strip of red LEDs for the brake lights as you mentioned.
 

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There are three rows of Led's....all clear when off.

With turn signals on, the top and bottom rows change to amber. With brake on, the middle row changes to red.
 

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sportrider said:
The power output is less with LED's, BUT they are definately much brighter!

Plus as an added benefit, they virtually last forever.

Go get some Bob!
You might want to read what I said more carefully, I think. I was just trying to point out that LEDs get their apparent increased brightness, by focusing nearly all of their lower total light output, in one direction. This is no different than putting a lens system on an ordinary incandescent bulb to collect all its laight and focus it in one direction; it is just a lot more convenient.

LED lifetime is less than one may think. They constantly get dimmer as time passes from the moment they are first turned on. A typical "lifetime" spec for a high power, high brightness LED is 50,000 hours until it reaches half brightness. Agreed, that is "virtually forever" for a brakelight that flashes only intermittantly, but the "lifetime" is still not what many people think.

Further, LED lifetimes are DRASTICALLY reduced if the LED chip inside is operated at temperatures higher than about 70°C. That may sound like a pretty high temperature that won't normally occur, but in fact it is a serious issue with high output LEDs. Self heating is serious enough that a typical high brightness 1 Watt LED requires some form of effective heat sinking. Without this, chip temperatures can easily hit 150° in a few seconds of operation. Many people who design high output LED accessories are either ignorant of this face, of are ignoring the problem. Lumileds has some good data on this on their website as I recall.

The lifetime issue is really a red herring, since you can buy a lifetime supply of standard brake lamps for a tiny fraction of the cost of an LED brakelight.

Personally, I'm perfectly happy with my ordinary tail lamps and signals, but that's just my own preference.

Bob.
 
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