sachs 504 hardwire help

My switch stopped working and I’m trying to hardwire my headlight and taillight on my sachs sparta, without success. I’ve read through the other postings surrounding hardwiring sachs, but cannot find anything specific to my application.

Wiring diagrams found on the forum as well as myron’s have not been helpful for actually hardwiring the lights. Any help is greatly appreciated. I know I may need to provide more info...and I will, in response to questions.

I also have a new 6v headlight on order from treats, because maybe the stock

one shit the bed, I don’t know.

Thanks in advance for any help the community can provide.

Re: sachs 504 hardwire help

♣Slew Foot♣ /

Blue black wire from the Magneto ground to the frame that is the negative ground return from the tail light the blue black wire that went to the tail light rather coming from the tail light also ground to the frame that should get you Spark

Re: sachs 504 hardwire help

knoll d’grasse /

Thanks for the response. I should mention the bike has spark, and no trouble starting. Kill switch works, but the switch for the lights doesn’t. I want my lights to automatically turn on with the motor. The light switch was wired with a grey (ground), white(closed?), red(horn) and yellow (open) cable that went to the ht(?). I’m running yellow to the light from yellow from the stator, but the headlight isn’t working. The headlight has an internal ground, and a black and white cable for hi/low beams. I spliced the two together and then connected to yellow.... nothing. I’ll follow this up with a picture of what I am working with here.

Re: sachs 504 hardwire help

knoll d’grasse /

photo attached

1991AC99-57A4-4582-9769-53DBE60358C8.jpeg

Re: sachs 504 hardwire help

♣Slew Foot♣ /

I know that internal headlight ground is actually part of that blew hard wire fix basically the bike doesn't have a ground until that blue wire is on the frame

Re: sachs 504 hardwire help

♣Slew Foot♣ /

You see what they used to do is run the negative ground through the tail light there is a ceramic resistor in there that gives it the running light the negative ground then goes back to the stator which in turn left the other coils work it was a safety feature so that if anything didn't work the bike wouldn't idle or start right you will have a spark but it'll be weak or orange or just the not enough to fire a compressed chamber it will spark on the side and it will look functional but if you had a small engine test plug you would realize it didn't have the snap that it should

Re: sachs 504 hardwire help

knoll d’grasse /

So if i’m understanding you correctly, the blue wire at the bottom of the picture needs a ground to the frame? If so, from which side do i run the ground? blue side or black? Hope that makes sense.

Re: sachs 504 hardwire help

♣Slew Foot♣ /

What you're trying to accomplish is taking the loop that goes to the tail light and bypassing it and making it go straight to the frame on both sides so that it effectively makes the bike the ground

Re: sachs 504 hardwire help

knoll d’grasse /

connected bottom blue to ground to frame: no luck. won’t start now. i did change the tail light, but have that grounded to frame as well.

i am clearly missing something when it comes to the theory behind electrical.

i’m also a visual learner, any references to my pictures would be super helpful for me.

F62E2ABF-EB84-4DE2-B858-BBDC0EA49708.jpeg
63CFC033-FC02-4BE6-ACF3-0E4B4E989A34.jpeg

Re: sachs 504 hardwire help

♣Slew Foot♣ /

There is also an issue because there are bushings that isolate the engine from the frame so you have to have a ground strap from the engine to the frame try that and see if it works

Re: sachs 504 hardwire help

knoll d’grasse /

that worked! i went frame to motor and disconnected ground to blue and she fired right up, kablam!

head light hardwired successfully.

but the tail light doesn’t light up. hah, of course there would still be something left to figure out. it’s a 6v led from treats that is supposed to run on 6v. it’s grounded, but somehow it’s not getting power? should i run it to yellow?

Re: sachs 504 hardwire help

♣Slew Foot♣ /

Easy peasy man the rear original OEM lamps for that AR 3 volt + 2 volt so you could basically just like take apart one of them little LED flashlights and fashion a brake light and a thing off of them use a one that takes a single battery for the running light and use the double for the break cut them up make them as small as you can like their buttons put them right on the fender and you cut them it right angle just wire the positives and leave the housing as the negative ground and they'll work just like tail lights

Re: sachs 504 hardwire help

just runa a parallel wire from the headlight, which clearly works, back to the tail too. bingo.

check your wattages on the bulbs are si milar

Re: sachs 504 hardwire help

knoll d’grasse /

will do- it’s the vertical fixation led tail light from treats.

i’ve seen that some people were able to run it without any modification, and it’s advertised as plug and play with 6v, so i’m hoping it’s just a power issue.

Re: sachs 504 hardwire help

are you running that series or parallel with the headlight? do parallel

Re: sachs 504 hardwire help

knoll d’grasse /

all set. ended up removing the led tail and reinstalling the stock taillight. connected power to tail to light/power from stator and she’s lit up like a christmas tree. thanks for all the help homies

Re: sachs 504 hardwire help

♣Slew Foot♣ /

I really do love when I help somebody rewire these things that I'll go through and I'll tell him how to wire the whole thing and then they go it doesn't work and then I tell him to put the ground strap on and boom like you said lights up like a Christmas tree

« Go to Topics — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account