QT50 headlight solution finally.

[sillygrifter]

I blew my light & the sealed lens bulb is now $57.00 . I read this & the others who left Ideas. I found a much easier replacement which cost me a total of $10.00. I used channel locks to crush & remove the bulb that is soldered into the sealed headlight unit (this required some shaking to remove the filament & glass particles). I went to my local auto-parts store & purchased the cheapest Halogen auto replacement bulb i could find (this is the small replacement bulb, not the large headlamp) it was $7.94 . I also purchased 1 tube of super glue $1.94. The halogen car bulb is 12 volt but fits perfectly in the hole left in the sealed lens after removing the original filament. The plug on the qt50 fits perfectly on the halogen bulb. I simply super glued around the seal to make sure it holds tight. I also run my qt without a battery. this solution works perfectly! even the high beams work.

[xrongor]

i went down that path. personally i used both an 8$ halogen bulb and an 1157 bulb (amongst other things) over the course of my quest for a real solution. imho neither was satisfactory. neither gave a decent light pattern out of the stock headlight bucket even if you adjusted the light in and out to hit the sweet spot. and the 8$ halogen didnt hold up to the unpaved roads around here. broke the filament. in all honesty i thought the 1157 did a better job and you can get those two for a buck.

so imho, if all you do is drive on pavement in mostly already lit territory, maybe its ok. I drive down washboard gravel roads at night in the pitch black except for what light i bring with me and was completely unsatisfied. busted filaments and poor light spread were all i found from trying to rig a bulb into the existing bucket. and again, the 1157 was imho superior to a headight.

your mileage may vary.

randy

oh ps. that superglue is probably gonna crack and fail like it did for me. id use silicone or even just duct tape when it does.

[sillygrifter]

I have only 50 miles since the fix. So far so good. mixed driving though mostly on paved roads. I was wondering how you got the 1157 buld through the little hole in the rear of the sealed beam unit? Anyways I was riding last night & was impressed with the amount of light from the $8 halogen. I will keep you informed, how my fix works in the long run.

[xrongor]

i cut out the whole bulb from the back side with a dremmel big enough to fit the 1157 in. then i took a saw to the taillight of a junked car so i had a nice socket and easy way to change the bulb. then i cut a spray paint can lid into a tube to adjust in and out distance for best beam spread. just duct taped the whole thing together. id show a pic but i cant find the thing. i may have tossed it.

that was actually the solution i was using until i got a better one. the tape held fine although if it ever started looking bad i was gonna silicone it. its biggest problem was that i couldnt get a wide beam without sacrificing direct frontal illumination. if you found a bulb you are happy with id just stick with that. the main thing i liked about these particular lights is they give loads of light using cheap bulbs.

led headlights are almost there, but not quite. very soon!!!! yay!!!!

randy

[sillygrifter]

Thanks randy.
I did not alter the original hole. that halogen bulb fit snug, I probably did not even need super glue. I put another 20 miles on tonight (all pavement) it does get brighter and dimmer as i ride but I get lots of illumination. when that original headlight blew out, it did as you said & got real bright & then blew, then a second or two later the 1154 tail lamp blew also.
I will continue with this fix until it fails as i do not have the fancy tools. Also initially, after reading your post i did try to order the honda assembly from the link you provided but they do not ship to addresses different from the billing address on the credit card. So that along with reading other suggestions led me to this alternative. If it fails I will be doing your methoed.
Man I sure do love boogying around on this little machine. I'm 38. I had a suzuki fa 50 when i was 15. It is almost identical to the qt50 even the red color, however the suzuki i got brand new for $450.00 in 1984. I just got this older 1979 qt50 a few weeks ago. I cannot believe how good it runs. Hopefully it will last me until I can afford a newer model.
I also noticed (after googleing yamaha qt50) that there are alot of parts & whole running qt 50's available on e-bay.
Thanks for the replys & the initial post helped me immensely. Happy 4th of july.
thanks again
Matt

ps: for a minute I thought maybe it was you selling those honda light assemblies.

[crx7]

I bought this a while ago, but haven't installed it as my ghetto rigged 12V Xenon is pretty good. I just bought a nice bright 12V bulb from the autoparts store, used a propane torch to melt the solder on the old bulb and pulled it out. Just JB welded the new one in place. No issues since and it's really bright, other cars notice the light.

[xrongor]

i bought a stock voltage regulator for about 10 bucks shipped off ebay for my QT that does have a battery, but no regulator. installed it using the mount for the rear rack and a longer bolt to go through both. then just tied into the blue wire that feeds the headlight hi/lo beam switch like it does on ones that it comes stock on (post 83 i believe)

i cant say absolutely for certain it helps but the one i own with the regulator has had less headlight problems. since installing it a couple months ago i havent blown a headlight but i also got a new battery this year.

i am certain it wont hurt...

randy

[John]

Solution.

[John]

www.dratv.com Lots of parts etc there and headlights/bulbs that will work.

[dpappa]

Sorry to bump an old thread.

I keep reading that a 12v light will work on a 6v system, but it will obviously lower the current since its half the voltage.
I feel like this would be a safe move to prevent voltage spikes, but it would make the headlight half as dim.

Can anyone confirm this? I would like the headlight to be just as bright as my 6v stock was. Thanks!