***Originally posted by member Jabcb***
This halogen H4 headlight upgrade works for these 1973 & later models:
GT250 K-B
GT380 K-B
T500 K-M
GT250 A-B
You can upgrade to an H4 headlight that's for certain GS bikes.
The GS headlight rim 35111-45231 fits the listed headlight buckets.
The GS halogen H4 headlight 35121-45230 fits this rim.
The rim + the various little pieces you'll need are still available:
http://www.powersportspro.com/pages/Oem ... nc/GS750L_(1981" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;)/HEADLAMP/02830002/5602830022
The headlight is listed as unavailable, but it may be available under a different part number.
If the headlight is still available with a different part #, then maybe one of the Suzuki gurus knows the #.
The headlight is from the GS L models and does look a little different than the stock two-stroke units.
Suzuki used several different headlights on the GS models. If you go the eBay route, you'll need to check to make sure you've got the right one.
Bikes with this headlight:
81 GS550T
81-83 GS650GL
80-81 GS750L
80-83 GS850GL
80-83 GS1000GL
H4s are available in 35/35W, 45/45W & 55/60W.
I'm using a 45/45W H4 bulb on my T500M.
On the GT250 you might want to first try a 35/35W H4 bulb.
The GT380 has a Denso or Kokusan alternator. Of these two, the Denso provides a good bit more output.
See page 18 of:
http://www.ozebook.com/compendium/suzi/suzidata1.htm" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
Early GT380s had 35/25W headlights & GT380A/B had 40/30W headlights.
The GT550 has the same alternators. Think the GT550 had 50/40W headlight.
On the GT380 you could use 45/45W H4 bulb.
The GT380 battery is a good bit smaller that the GT550's.
Use of LEDs would reduce battery load at low rpm. (think idling at red light while using turn signals & brake light)
On a GT380 with a Denso alternator, modern rectifier, modern regulator & modern high-output battery & maybe some LEDs,
I'd give the 55/60 H4 a try.
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BAS (Bike Acquisition Syndrome) - have too many bikes but still have room for one more
1975 & 1975 Suzuki GT750
1974 & 1975 Suzuki T500
1969 & 1971 Suzuki T350
1973 Suzuki GT250
1986 Honda CB700SC
2009 Triumph Bonneville SE