I've always been concerned on the motorcycle at night about visibility from the side, particularly when stopped. It's also tough to see blinkers when a cager is right next to you. A good headlight and indicators are great but when you're a sitting duck waiting for a light to change I've always wanted a little more. There are a few aftermarket bar-end blinker systems out there but they're pricey and it didn't seem necessary to achieve what I wanted to do so here's what I did.

A few notes first. This will require a bit of soldering and willingness to dig into your motorcycles wiring. You'll also be drilling/cutting into your grips. I did this on a set of Kuryakyn iso-grips that were already on the bike. You could likely do this on standard rubber grips too but it wouldn't have quite the same fit/finish/look as it does on a set of metal ended grips. I'd even consider perhaps sandwiching a pair of washers on the inside/outside of the grip if you wanted to use the rubber ones but that's beyond the scope of this. Additionally you could drill and use a tap to run threads into the metal if you didn't have the ability to remove the grip end as I did. All colors/sizes/measurements are subject to your needs. Total cost of the project was about $10.

Materials:

1 pair of yellow 'eagle eye' LEDs- I got 18mm 9W yellow with chrome housing- Amazon away according to your desired dimensions/color scheme/etc.
wire strippers
solder/soldering iron
Drill and bits large enough to make a hole for the LED-
a few 200-300 ohm resistors
heat shrink tubing
basic hand tools to open headlight/indicator covers
a multi-tester might be handy but isn't strictly necessary
9V battery for testing purposes

Step 1: Step 1: Disassembly

Remove the throttle side grip. This may be very easy or very difficult, depending on how yours is installed. For mine it was a simple matter of taking off the throttle cable housing and the whole thing just slid right off. If your grip is properly glued to the throttle tube then the tube should stay attached. If it doesn't, or seems loose, adhere it again since that could be very dangerous. You'll end up leaving the throttle cables just hanging in the housing. It's pretty obvious which is which but don't lose track of them. This is also a great opportunity to lube those cables so give 'em a squirt!

Remove the clutch side grip. This one is most likely just stuck on there with gobs of adhesive. Carefully use a long thin screwdriver or compressed air or lubricate it with unicorn tears, it'll come off eventually, quite possibly in 7 pieces.

Step 2: Step 2: Drill Baby, Drill

If you've got metal ended grips like mine you'll just need to drill the correct size hole in each grip to accept the LED light. I found it easiest to do while the end was still attached to the grip but you could take it off if yours come off. It's fairly soft metal but i did take 2 passes with two different sized bits just to be safe. I also took the ends off to make threading the bolt on easier and for fishing the wires through.

Be careful at this point since different LEDs seem to have varying degrees of quality control. Most everyone else I've seen use these LEDs feel the need to add extra silicon or epoxy or something to add some additional strain relief to the wires that come out the back. Mine were actually very secure. I'd also make sure to test the LEDs first (just a simple 9V battery will work fine here, and keep it handy since you'll need it later. + to red, - to black.

Step 3: Step 3: Snake It!

This is the hardest part. Most motorcycle bars have weights in the ends of the handlebars. They are there for a reason and please don't remove them unless you want to have arms made of jello after every ride.

On the throttle side you'll need to snake the wires under/in/through the handlebar. Most bars either have a set screw that will allow you to temporarily remove this weight or (as was the case with mine) have them welded in but with enough room to just snake the wires under/around it. Worst case you could probably drill lengthwise through it but any weight you remove you should probably add back in again. You should also find a small hole somewhere on the back side of the throttle cable cover. If there isn't one you should be able to drill a very small hole somewhere for these wires to exit w/o compromising the integrity (at your own risk of course). Careful of burrs in general with wires involved and in fact a layer of heatshrink wouldn't be a bad idea.

[A quick edit after 6 months of use- I now recommend a substantial amount of cable reinforcement/strain relief on the throttle side. Since it's constantly being twisted those tiny wires just won't last where they exit the threads on the LED. A substantial glob of your flexible adhesive of choice and then small/medium layers of heatshrink should do the trick. Sleeving the entire wire wouldn't be a bad idea either. Will report back again in another 6 months.]

On the clutch side I just ran the wire right under the grip, being very careful not to pull the wires out of the back of the threaded led housing. You could snake this one through the handlebar as well but since this side doesn't twist I didn't bother.

Step 4: Step 4: Wire It Up

I'm limiting the instructions here since every bike will have different wiring and access. If you take the covers off your front blinkers and follow the wires back they may terminate in the headlight bucket or under a cowling somewhere. There will most likely be 3 wires. One is a ground and you can tie the black wires from the leds to it or just terminate them to any exposed metal point on the bike. The other two are your running and blinker lines respectively. Circuit test or just use the positive led line to determine which is which. One will be off when the lights are on but will pulse when the blinker is engaged. At every step along the way below I stopped and tested the LED with a 9V battery to make sure nothing got crimped/cut/messed up.

I'm not an electrical expert but I did spend a little time researching these particular LED's and then did a little math. They're 9W LED's and at 12V put out a great deal of light. Rather than potentially blinding folks next to me at night I chose to dim them down a bit by adding a 240 ohm resister in line on the positive (red) line. It just happened to be what I had a small bag of sitting around. You could try higher or lower if you wanted them a bit brighter or dimmer. LED's draw very little current so I'm not worried about overtaxing the system by tapping into the existing blinkers. Assuming your existing blinkers are standard bulbs you don't need to worry about the 'hyperflash' thing that happens when you replace the entire assembly.

Solder it all up, make sure you put the heat-shrink tubes on first since you can't put them on later, shrink it all away and then carefully wrap/tuck to your hearts content. Enjoy!