Depends. HID though. LED won't fit in the housing and will expose the housing to debris and water since it can't be sealed due to the heatsink/fan on the back. Combine that with LED being direction and not as bright, there's little improvement to be had from them. Especially in a housing that wasn't designed for LED bulbs.
But if you do put those in there, they will probably last until the year 2034.:wink:
I actually just fitted led to my gen4,I used a hole saw on the oem plastic cover that allows access to the globes!Skydork is correct about the led not fitting because of the length of the heatsink and fan but you can do it!all that is showing on mine is the ass end of the led globe!its nice and neat with the cover and has minimal gap around the led globes!
In my Gen2 I'm running DDM Tuning 35W 5000K HIDs. They are a nice white, none of that blue crap, which I suppose is just personal taste, but I don't like it and wanted white. Easy install. Trying to find the LEDs that I used to match in my city lights. Not sure if your Gen4 has city lights though, but I'll try and post anyway.
EDIT: Part number for the matching LEDs for the city lights on my Gen2: 194LED-5x5050LED.W. Not much help for you, but I think the 5050 is the number that corresponds with the color of the light.
My gen4 oem globes are H7!I purchased the equivalent in led,s and a much whiter light!in Australia all motorcycles must have their low beam h/l on at all times and it comes like that from the factory!when I fitted my low beam globe first and left the high beam oem globe in to see the difference in my shed!honestly the oem high beam halogen globe compared to the led low beam globe was like yellow and white!Im running a 40w led on high and Lo,I am going to use a multimeter to actually check the current draw of the H7 and led globes!Doing a quick search on the web it appears the led,s draw less current for sure!