i am writing in connection to where the thread stArted .i got few dozon leds which was quite expensive big(8 mm or more i guess),can handle 3 volt alone!!so i attached 4 of them in serise on a veroboard and did a circuit of 4 rows of leds total 24 leds.and it can with stand 12 volt directly,no prob.i started the bike revved it,no prob...also blazingly bright whithout any focal point.but must say after putting inside the pulsars back light just like master abhi did ,i realized the brightness is low in compared to stock 5/21 bulb.
now arent you guys are worried that there can be a visibility issue at night when riding through highways.......i feel it tremenduslyyy.....

i mean its even low then a 5/10 bulb i used,,,
i am not at all against the mod,but i am in fear that trukies or cars wont be able to see my ttail lamp and .................................................. .