LED Tail light problems

nick20555

Living life 2 strokes at a time
Jun 23, 2014
690
149
107
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Just outside Evansville, IN
I ordered this tail light last week to put on my blaster:
http://www.ebay.com/itm/311528827850
I wanted an LED tail light because they are bright and don't take as much to power them. My blaster is an 04 so it has the problem where my lights dim real bad when trying to power the brake light circuit (reason for getting the LED). I do trail riding with my buddies occasionally and a brake light helps prevent a lot of rear ending.

I went to test it yesterday but did not have much time to investigate. The wires are not labeled and there are no instructions so I just assumed the grn/yel wire was my ground and plugged the other two into the running and brake wires. When I started the blaster the LED would not light for running lights but did light when I hit my brakes.

Could it simply be that I have my wires backwards or do I have something more going on? I have not modified any of the electrical work (besides no tors, parking brake, or oil tank).
 
I think your problem is its an LED tailight. You cant just hook up a tail light onto the blaster wiring, you have to convert the stator AC current to DC current.
 
I was told by others that you can just slap one on there now that LEDs are getting more advanced. But maybe I'm having issues because I got an 04 and not the 88-02 where that might be the case. I would really like to avoid complex electrical mods if possible but I really hate the stock lighting. And I don't really have room for a battery now that I have the CFM airbox.
 
Hmmmm IDK about that. Yes they are getting more advanced but only special mad LEDs will run off of AC current from what my research is telling me...
 
Ok let me explain a little more, here is a graph on the 2:

With DC currnt you have constant voltage the entire time. But with AC current, you will only have power flowing to the LED when the curve is at its peak. So everytime it peaks at the bottom, no current to the LED. So you will have flashing lights the entire time. An LED actually ALREADY flashes on and off, just really fast so our eyes cant pick it up. but if you have every watched an LED through a camera or something you will notice it due to the exposure of the camera. So with an already flashing LED and then you add current that makes it go off an on, it gets really confised as to when it should light lol

dcacvis1.gif
 
Yeah, I understand basic concepts of current (I had to take 2 semesters of circuits a few years ago). I'm a mechanical engineer tho so I try to avoid the subject lol
 
When I did my test and got the brake to light the LED, I noticed that only at very low rpm it has a slightly noticeable flicker and I assumed that was due to the AC current but it was not noticeable unless the rpm was at idle. That's not so much a big deal to me but I would like to get both the running and brake light functional
 
I also thought maybe the problem could be due to an adjustment needed in the resistance to get the running light visible since it was probably designed for a DC circuit
 
Well I went out and put the wires on a 9V battery and found which one was the ground. I had the wrong one as the ground and the light is now working as it should. It has the slight flicker at idle but I guess I will always have that unless I wanna convert to DC
 
There area bunch of lights for crotch rockets that are called "Blasters" , not universal fit, might have had built in turn signals too.

No matter, still looks better than anything I've seen at like Autozone or TSC.
 
yeah, it was hard for me to find one with a clear lense (not smoked) and I didn't want one with a license plate light or turns because there was no need for either. Glad I could find one as cheap as I did though. The lense had a huge crack when I got it but looks like the seller is either going to refund me or ship me a new one
 
Since I know there was a little confusion (at least on my end) on whether a blaster could run an LED tail light designed for 12VDC, I thought I would post a video on how my LED tail light turned out. It was a cheap LED tail light that you can get for less than $10 on eBay (link posted in the posts above) designed for 12VDC quads. I did not have to do any modifications to the electrical system to get it to perform like this. It does not dim nearly as bad as the factory 03+ tail light does at idle. It does have a very quick and subtle flicker at idle but the video exaggerates it a little. It isn't as bad as the video shows. But I think it works better than the stock brake light. I also noticed that it did not dim my headlight when I hit the brakes to power the brake light which the stock tail light does badly.
http://vid44.photobucket.com/albums/f35/nick20555/20160406_201650_zpsjfkkk0zf.mp4