Pathetically Slow Flasher & LED Usage

I had
The snip is from @XSLeo. He's reliable.

I had replied earlier....

Thanks for that!
That particular unit doesn't come up in a search on their website. It is rather old.
I'm moving forward with a two prong unit. As stated earlier, folks are using them with apparent success.
I guess I'll just be abandoning the ground wire. :shrug:
Yes, on the 75 there is no self cancel. That came along later.
On these bikes at idle the voltage will be a bit low. Around 12-13 volts. The turns draw a lot of current, thus draws the voltage even lower. Low enough so the turns won't flash.
Going through the lighting circuits of the headlight and turns, cleaning and tightening all the connections will reduce the resistance in these circuits. This lessens the current draw so it helps keep the lights flashing and bright.
I often recommend starting at one end of a bike and working to the other cleaning and tightening all the connections on the bike. This improves all the electrical systems. This lessens current draw and puts less strain on the charging system. It can even fix problems before they become problems.
REPETE I responded to your PM. I'll just repeat some of it here for others that may have questions.
On the 75 there are two indicators lights on the dash. One is for the headlight and one is for the brake/tail light. These lights light when they sense when the headlight or tail brake light blows.
They use the light checker and a diode. I'm not sure exactly how they work. I have removed them from my 75 when I built my own harness. If you add LED's to the 74-76 bikes just remove them.
On the 77 and later they added the Reserve Lighting Unit. This can be removed too. Just jumper from the L/B to Y/L. This bypasses the RLU so the headlight works.
There are several two prong flashers out there that will work fine. When you use them be sure when you plug them in the prongs go in the brown and brown/white wires. Don't worry about the black wire. It's a ground for the stock flasher.
If you can't line up the prongs to the B and B/W wires you can remove them from the plug and put them where they need to be.
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Thank you Leo!!!

On the headlight not working, Issue is resolved. Wasn't anything electrical or mechanical. With all the activity the high/low switch got pushed into a position in between that was not sending power to either. Frustration and unclear thinking along with good intentioned interruptions were running rampant at that point.
Somewhere along the way I went from having flashers working with the new bulbs and flasher relay (same as the one you recommended but with pin connectors instead of flat) to bulbs just coming on and not flashing.
When the LED bulbs were working properly I also had the the warning light on the console flashing. When I was trying to figure that out is when I blew the fuse and I think I may have also damaged the new flasher relay. I was trying the wires in different positions. Now I can't get them to flash.
Having a good intentioned helper with me was only adding to my confusion - I work better alone.
Later last night I went back to square one... I put all the stock bulbs back in and the stock flasher. They still didn't flash (bike not running and hooked up to a battery tender) which is something they always had done - albeit dim and slow. Interestingly, now they're bright!!! :umm:
Lastly, when I walked away from it last night, I failed to turn the ignition key to off. Even with the battery trickle charger on it this morning it was stone dead. :mad:
On a positive note, convinced I damaged the new flasher relay I went to Super Bright LEDs this morning to re-order and up pops the one you had recommended with the flat spade connectors. Still the same part #. Interestingly, when I originally searched for it the search results yielded nothing.

At this juncture I'm thinking I first need to "get back to even" which means stock bulbs, flasher and working. Once operating properly then make the change over to the new bulbs and flasher relay. If all goes as it once did, I should have working LED flashers and taillight as well as the annoying console light flashing. And this time I'll simply pull the bulb.

My NEW concern is can I get back to where I started? Because last night, I couldn't. And it's not like there was any wiring disturbed other than at the flasher connector. I'm hoping I didn't create some sort of electrical damage to the bike..

I'll have more to report this evening assuming the battery comes back to life today.

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Again I relied to the PM and just wanted to add to this post that the LF1-S flasher works with the stock bulbs as well as LED's.
AS I recall that flasher can handle up to 150 watts of bulbs. When I first got it I tested it with just one LED bulb and it flashed that. I think it has a minimum draw but t's so small as to be of nothing. But 150 watts of lights would probably stall the bike.
All LED's are back in along with the LED Flasher Relay.
Everything lights up, but no flashing. When I blew the fuse it's likely that it had to do with me losing focus that the relay has a supply side and a load side. I had flipped the wires! Based on my presumption yesterday that I damaged the relay there is another on it's way. Probably be a few days before it arrives.
I also went ahead and removed the console "bulb malfunction" indicator light. It's become apparent that'll never work properly so it's now sacrificed for the greater good.
I am anticipating that when the new flasher relay arrives all issues will be resolved - until I open up the can of worms being an LED conversion of the headlight and console lights :eek:
If you remove the light checker, that will stop the light from flashing. There is a way to use that bulb as a charge indicator light.
I don't recall exactly how it's done When done right it comes on with the key switch and once the engine starts and the charging system starts working the light goes out.
It was 5twins or Pamco Pete figures it out.
Thanks Leo,
Very creative but for me a project for anther day.
For now I'll be happy to get bright flashers and taillight.
Then explore if there's been any proven success in a headlight LED conversion as well as the console bulbs.
More to come - waiting on the USPS

Success!!! :D
My replacement Flasher Relay arrived yesterday. I now have beautiful bright flashers and taillight!
I'd really like my experience to be helpful to others, and most importantly those with a 1975 XS650B.
I don't know if the '75 is unique in that it has that console "bulb out" warning light feature or if that is found on other years, but it was my unwillingness to give up on it's non-stop flashing after the installation of the LED's where I went astray and ended up frying the Flasher Relay.
In summation, for any others wanting to make the change over to LED's (again, I'm specifically addressing a 1975 XS650B) I'm hopeful that the below instructions based on what I learned is helpful you:

1) Resign yourself to the fact that you'll need to abandon the functionality of the "bulb out" warning light. You can either watch it flash non stop or simply remove the bulb.
2) Flasher Relay must be of a no load style for use with LED lights. They can also work with standard bulbs and improve your flashing performance.
3) Order the correct materials. I don't believe that as of this writing you're going to find the more standard looking round or square plug in flasher relays that'll work with the stock flasher connector. Those that are available have their flat spade contacts in the wrong configuration to simply plug in. I emphasize that I'm speaking specifically for a 1975 XS650B! Using SUPERBRIGHTLEDS.COM as a recommended vendor will streamline your search and you'll want the following:
  • Flasher Relay LFS-1-FLAT
  • Flasher Bulbs 1156-A18-T 325 Lumen Amber Bulb(s)
  • Taillight Bulb 1157-R19WS Red/White Bulb
Thanks goes to Leo on the tip of using the "flat" Flasher Relay. They also have the same relay in a pin connector design which would require some minor wiring work to change the ends or introduce a female pin x flat spade jumper wire. This is what I had used at first. It will work. (SuperBrights part # LF1-S-PIN).
Concerning the bulbs, there may very well be others that'll work - different lumens, etc - BUT THIS FORMULATION equates to proven success and you'll be spared any guessing or questions. Have trust!
4) THERE ARE NO INSTRUCTIONS SENT WITH THE FLASHER RELAY AND THERE ARE NO ENGRAVED INDICATORS ON THE FLASHER RELAY BODY IDENTIFYING THE WIRE LEADS!!! You must look at the flasher relay spec sheet on the SUPERBRIGHT.COM website to identify the supply side lead and the load side lead. In the case of the LFS-1-FLAT the GRAY = SUPPLY and connects to the BROWN wire in the wiring harness' flasher connector. The BLACK = LOAD and connects to the BROWN/WHITE wire in the wiring harness' flasher connector. Failure to follow this will result in damage to the relay.
5) The BLACK WIRE in the wire harness' flasher connector will be ABANDONED. Don't spend time (as I did) questioning it - just accept it!
6) Enjoy the safety provided by your new really bright and low power demand LED lights!

Thanks again to All, and especially Leo.
I truly hope these overly explained instructions from my successful experience make for an easy path for anyone else looking to convert flashers and taillight to LED lighting on a 1975 XS650B. Lets all be safe out there!

If anyone knows for sure that any other model year is identical, please enhance this post so whatever help it is can be expanded to include owners of those other models as well.


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On he 70 XS1 and the 71 XS1 B the wiring is about as bare bones as it can get and have all the lighting you need.
The 72 XS2 and 73 TX650 had changes to add the E-start.
the 74 TX650 A added the warning lights for brake lining and headlight failure lights.
The 75 XS650 B and 76 C added the tail /brake light failure light.
The 77 D added the Reserve Lighting Unit and a resistor so if one beam on the headlight blew it would light the warning light and light the other beam at half power. When this happened no matter which position the headlight dimmer switch was in the headlight was at half power. This would let you get home or to a place you could get a new headlight. They also added the self canceler to the turn signals. .
The early 78 E they took out the brake lining warning light. Still had the tail/brake light warning light. Up to this point they used a single fuse. In late 78 and into the 79 F they switched to the 4 fuse block and changed from the 4 wire light checker to the 7 wire unit.
The 80 G Special II had the clutch switch that only let the starter work when the clutch is pulled. At least mine is set that way.
The 80 SG and the 81 H and SH they took out the brake/tail light warning light and got both the clutch switch and side stand switches and relays so not only do you have to pull the clutch and put the bike in neutral to start but if you put it in gear without the side stand up the engine quits. No riding around with the stand down.
They stayed this way till end of production.
There were minor changes in the wiring, mostly about how many lights illuminated the dash gauges or how many turn signal indicators on the dash.
Hope this helps someone on there projects.