Halogen to LED conversion

All to do with wiring, charging or just trying to figure out whats gone wrong.

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SudookyT350
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Halogen to LED conversion

Post by SudookyT350 »

So how risky would it be to replace every bulb in my T350 with LEDs? The halogen bulbs are pretty much worthless, except for the 3 indicator lights on the tachometer.

Here’s the specs of the current bulbs:
•5 Speedometer/Tachometer bulbs- 12 volt, 3.4 watt (Part no: 51173-18510)

•4 Turn signal flasher bulbs- 12 volt, 23 watt (Part no: 09471-12006) #US1073

•Brake light bulb- 12 volt, 32/4 candlepower (Part no: 09471-12002)

Anyone with any advice or options on the best bulbs for a good price would be appreciated. The information I sent above is all that I could find.
“Life is the art of drawing without an eraser with only one sheet of paper.”
x2 1970 Suzuki T350II’s, June flavored and July flavored. 1974 Honda CR125M Elsinore
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jabcb
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Re: Halogen to LED conversion

Post by jabcb »

Don’t have specific bulb replacement suggestions.

Stock, a T350 does not have a voltage regulator. As a result, voltage as high as 16V at high rpm is normal. Switching to a modern rectifier/regulator will protect the LEDs from that high voltage.

If you switch to LED turn signals, then you will need to install a diode kit for the indicator light. Otherwise you could end with all 4 turn signals flashing, or the indicator light only flashing for one direction & not the other.
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SudookyT350
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Re: Halogen to LED conversion

Post by SudookyT350 »

So if I were to install a modern voltage regulator, will it have to output 12.8 volts to match the electrical system’s running voltage? Or can the regulator have a higher range, say for example 13.5 volts max?

I’m still learning more and more about different electrical components. (one of the cons of being young in a “old” mans hobby) If I get some advice or knowledge from more educated people, you’ll bet I’ll do plenty of research/trial & error to make sure it’s done properly.

I’ve found multiple youtube videos making & testing indicator diodes, and they’ve been pretty helpful. But would I have to install a diode for each individual turn signal? I see some indicator diodes in a 4 pack for sale and some are only selling one.

It seems this forum is the ONLY reliable source I have, and I’m glad there’s always been someone that has an answer to my questions. Hate that I receive help on here but i’m too inexperienced to give help to others. Maybe one day when I have more motorcycles than I can count, I’ll finally be able to help somebody that’s stuck in a rock in a hard place.
“Life is the art of drawing without an eraser with only one sheet of paper.”
x2 1970 Suzuki T350II’s, June flavored and July flavored. 1974 Honda CR125M Elsinore
karl pa
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Re: Halogen to LED conversion

Post by karl pa »

With a good charging system, a modern rectifier/regulator will give you around 12.8 volts at idle and 14.2 volts at high rpm. Most are not adjustable, but I think some may have adjustment capabilities.
My understanding is on the twins, the modern regulators drain excess voltage to ground, not like the triples, were they actually regulate alternator output.
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SudookyT350
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Re: Halogen to LED conversion

Post by SudookyT350 »

That sounds about right to me. I’m not familiar with triples, but I would assume they have the same electrical brains as the twins. When the key is turned one click, only one generator is charging the system and no running lights are operating. All 3 generators will charge the system at 2 clicks up on the key, and the running lights and headlamp are operating. If the triples are the same, I shouldn’t have too much trouble making it work correctly.

Also: Quick question, is the 3rd click up on the ignition key a kill switch? Mine dies when it’s on the 3rd click and I thought I’d make sure that’s supposed to happen. Lol
“Life is the art of drawing without an eraser with only one sheet of paper.”
x2 1970 Suzuki T350II’s, June flavored and July flavored. 1974 Honda CR125M Elsinore
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Alan H
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Re: Halogen to LED conversion

Post by Alan H »

SudookyT350 wrote: Sat Nov 13, 2021 9:30 pm That sounds about right to me. I’m not familiar with triples, but I would assume they have the same electrical brains as the twins. When the key is turned one click, only one generator is charging the system and no running lights are operating. All 3 generators will charge the system at 2 clicks up on the key, and the running lights and headlamp are operating. If the triples are the same, I shouldn’t have too much trouble making it work correctly.
Nope, the triples are completely different and use a 3 phase alternator, 6 diode rectifier and an excited (electromagnet) rotor with a regulator that controls power to the rotor. This limits the output of the alternator as the battery voltage rises, and increases the alternator output as the battery voltage falls. Lots of info on them here if you do a search.
Also: Quick question, is the 3rd click up on the ignition key a kill switch? Mine dies when it’s on the 3rd click and I thought I’d make sure that’s supposed to happen. Lol
3rd click is ignition off and parking lights (if fitted) on. I believe all the smaller twins have similar systems - they were certainly like that on my 200s. Not sure about the 500s as I never managed to own one of them (yet!)
Again, info on twin charging if you do a search - I wrote some of it (and the triples!)

If you use led bulbs in the indicators, you will have to either fit resistors to each indicator, which makes it all a waste of time, or change the indicator relay for a led type. Trouble then is that the telltale bulb on the dash will allow all 4 indicators to flash simultaneously, so either needs a 3 connector double led telltale, or remove the bulb (which can be a 'test' fail.)
You didn't think this would be straightforward did you? :lol:
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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SudookyT350
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Re: Halogen to LED conversion

Post by SudookyT350 »

Ahh. I knew for sure it was going to be one of two things: either a nightmare, or a breeze. No in between. It would be worth all the work considering it is essentially making the ride safer.
“Life is the art of drawing without an eraser with only one sheet of paper.”
x2 1970 Suzuki T350II’s, June flavored and July flavored. 1974 Honda CR125M Elsinore
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tz375
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Re: Halogen to LED conversion

Post by tz375 »

See http://pinkpossum.com/Lights.htm for details but in short, if the system has an idiot light for each direction, just fit a suitable modern flasher can. If both sides use one common idiot light, you have to separate out each side with a diode for each side - not for each bulb.
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Re: Halogen to LED conversion

Post by dollydog »

i've done this conversion on my indicator circuit for all my gt250's. led bulbs in each indicator and one of those cheap, round, blue led indicator relays - i've never had one fail yet. take the indicator idiot light out and replace it with 2 single led's. get the ones with the long tails. wire one wire up to the black wire - left indicator, the other to earth. repeat for the other led, but the live goes to the green wire for right indicator, the other wire to earth. put a rubber bung in to keep them safe in the holder. on the indicator relay you'll see 2 letters on the bottom, probably B and L. there's a blue wire and an orange wire that goes to it. the blue wire DOES NOT go to the B terminal, it goes to the other one. the orange wire goes to the B terminal. it takes longer to type that actually fit. once i'd sorted the idiot light out my indicator circuit worked perfectly, until then i was pulling my hair out :D
cheers, dd.
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jabcb
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Re: Halogen to LED conversion

Post by jabcb »

tz375 wrote: Sun Nov 14, 2021 3:41 pm See http://pinkpossum.com/Lights.htm for details but in short, if the system has an idiot light for each direction, just fit a suitable modern flasher can. If both sides use one common idiot light, you have to separate out each side with a diode for each side - not for each bulb.
This is even easier if you get the Kuryakyn diode kit, or a similar kit: https://www.kuryakyn.com/products/719/diode-kit
I did the conversion to several bikes & have not had any problems.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
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tz375
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Re: Halogen to LED conversion

Post by tz375 »

Also available from Sparckmoto.com
dollydog
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Re: Halogen to LED conversion

Post by dollydog »

exactly what i was talking about - led's with the long tails :D i got mine off fleabay, basically for pennies. btw, wasn't mr kuryakyn off man from uncle? :D :D :D :D
cheers, dd.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
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tz375
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Re: Halogen to LED conversion

Post by tz375 »

Man From Uncle was a long time ago. You are showing your age DD. :lol: Not that I'm old enough to remember the series or the actors.. :oops:

The answer as the OP may have already worked out, is actually quite simple, but they have choices. With a single idiot light, they can buy or make a pair of diodes or they could change to two LED idiot lights. There's a bunch of small LED lamps on ebay from China that come with long enough leads and also with threaded bezels to fit them in place.
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SudookyT350
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Re: Halogen to LED conversion

Post by SudookyT350 »

dollydog wrote: Sun Nov 14, 2021 5:27 pm i've done this conversion on my indicator circuit for all my gt250's. led bulbs in each indicator and one of those cheap, round, blue led indicator relays - i've never had one fail yet. take the indicator idiot light out and replace it with 2 single led's. get the ones with the long tails. wire one wire up to the black wire - left indicator, the other to earth. repeat for the other led, but the live goes to the green wire for right indicator, the other wire to earth. put a rubber bung in to keep them safe in the holder. on the indicator relay you'll see 2 letters on the bottom, probably B and L. there's a blue wire and an orange wire that goes to it. the blue wire DOES NOT go to the B terminal, it goes to the other one. the orange wire goes to the B terminal. it takes longer to type that actually fit. once i'd sorted the idiot light out my indicator circuit worked perfectly, until then i was pulling my hair out :D
cheers, dd.
DD, check your inbox, I sent you a email yesterday I believe.
“Life is the art of drawing without an eraser with only one sheet of paper.”
x2 1970 Suzuki T350II’s, June flavored and July flavored. 1974 Honda CR125M Elsinore
dollydog
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Re: Halogen to LED conversion

Post by dollydog »

hi mate, no email come through from this side of the pond :D only water, gas, electricity bills, insurance renewal and several other bills. i'll check on my status and make sure my new email is on it, not my old one :)
cheers, dd.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
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