Many people are claiming for more light, and one way to get it, is to mount a 80/90 or
90/100 W headlamp. However, it's not a matter of simply replacing the lamp. There are some
things, you better should do before. F.e., check your bike for suitable relays (inside the
dashboard), and if lacking, install them. Obviously, TAs sold in Greek don't have relays
for headlight operation. If your bike is already equipped with relays, you probably should
install thicker cables (the green ones in diagram), and, maybe, bigger fuses.
Also, be sure to check your local laws, in some countries the use of stronger
headlamps is illegal!
Zervos Christos drew a wiring diagram, which I have posted here as a JPEG file (159 K). Originally it has been a PowerPoint document. When sending it, Zervos wrote:
Hello Deti, I attach the powerpoint file which contains the electrical diagram on how to wire a higher wattage headlamp (12V-100/90W) on a TA to replace the existing (12V-60/55W) one. I tried to be as explanatory as possible. I have also included (inside the powerpoint drawing) some "notes" which I consider important and have to be taken in account before one proceeds to do that headlamp "replacement". If you have any comments please let me know (Zevros). Of course some "disclaimers" have to be added, but you can use the same ones as with all the other "how-to-do-it" instructions posted in your web site.
All '87-'96 TA models sold in UK (E), France (F), Spain (SP), Swiss (SW), Austria (AR) and Italy (IT, IT-II) and all '96 TA models sold in Germany (G, G-II) are NOT stock-equipped with headlamp relays and extra fuses. I do not know about the after-96 models or the early US models. The '91-'95 TA models sold in Germany (G, GII) appear to have stock-equipped headlamp relays and extra fuses (2x10A). On those models, one could possibly only upgrade the existing wiring (by thicker cables) and replace the fuses (by 2x20A). BUT, headlamp main (high) current comes from the fuse-box and not directly from the battery. So it would be much-much easier to install new wiring and fuses (as per diagram) instead of upgrading the existing wiring harness.
Disclaimer: I cannot be held responsible for any damage and/or mistakes made when implementing this wiring circuit. If you're not going to install the relays and the extra fuses, stick with stock 55/60w bulbs. Otherwise you run the risk to burn your headlight switch and/or wiring harness. If you don't install the extra fuses, your ran the risk of getitng fire in case of an accidental short-circuit. If you're unsure of your wiring or electrical skills, find a professional to help you. Safety comes first.