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HogsRear
05-06-2016, 6:47 AM
Howdy all, I've been cruising all corners of the internet studying chopped wiring diagrams and I'm currently trying to make heads and tails of the harness I would like to run for my build. This is my first wiring attempt, and after a million drawings this is the diagram I have come up with. I'm looking to eliminate all bar controls and run a 3-way Hi/Off/Lo headlight dimmer switch and a car style Off/On/Start key ignition under the tank. I'm not convinced any of this is correct so go easy, and let me know if there are obvious changes that should be made.

Yes, I have seen the chopped wiring thread and the ones in there for the GS550, but mine is slightly different with the ignition and light switch and I just want to be really clear on how this should be set up before I go making any bad decisions.

Thanks in advance.

69407

Jasonisdico
05-06-2016, 8:54 AM
Looks right to me. I've done a GS550 chop and that's what my wiring looked like. Only exception is I ran a toggle on/off and push button ignition. And I don't run a rear brake light switch. I like being able to slow down without a cop seeing my brake go on. It's also cleaner.

Westboundbiker
05-07-2016, 9:21 AM
69433

So I made a couple changes.
First, you'll notice the addition of two wires coming out of your generator- unless you've got a PMG generator (which I don't think the GS series ever did), you'll need to apply 12V to those wires in order to get AC power out.
Second, you'll notice the routing of wires out of your starter. The way you had it wired, the lights only would have been on when the starter was cranking.
I also added some fuses- the one out of the R/R is critical (ask me how I know...). It will protect the rest of the system in the event your R/R looses the ability to R or R. Either way, you'll end up on the side of the road, but with a fuse, you won't end up with a fried battery like I did. The fuse after the coils and excitation wires- that I added so if there was an issue with wiring elsewhere, for whatever reason, your bike would still run, and you could still get home (albeit without headlight or taillight).

Also, I'd definitely recommend going and getting a Mosfet R/R. Only one I've found that doesn't just blow up within a couple hundred miles. I ran a cb750 one; it fried. I ran the stock one; it fried, and took the battery and most of my electronics with it (unrectified AC will do that). The Mosfet has been going strong for 1200 miles.

Jasonisdico
05-07-2016, 9:46 AM
69433

So I made a couple changes.
First, you'll notice the addition of two wires coming out of your generator- unless you've got a PMG generator (which I don't think the GS series ever did), you'll need to apply 12V to those wires in order to get AC power out.
Second, you'll notice the routing of wires out of your starter. The way you had it wired, the lights only would have been on when the starter was cranking.
I also added some fuses- the one out of the R/R is critical (ask me how I know...). It will protect the rest of the system in the event your R/R looses the ability to R or R. Either way, you'll end up on the side of the road, but with a fuse, you won't end up with a fried battery like I did. The fuse after the coils and excitation wires- that I added so if there was an issue with wiring elsewhere, for whatever reason, your bike would still run, and you could still get home (albeit without headlight or taillight).

Also, I'd definitely recommend going and getting a Mosfet R/R. Only one I've found that doesn't just blow up within a couple hundred miles. I ran a cb750 one; it fried. I ran the stock one; it fried, and took the battery and most of my electronics with it (unrectified AC will do that). The Mosfet has been going strong for 1200 miles.

You're right about everything. I think the guy had main power coming off the battery power post on the starter solenoid though, and not the starter wire. He sell didn't have a ground drawn off the solenoid, but obviously it needed that as well.

👍🏻🍻

HogsRear
05-09-2016, 10:22 AM
Thank you guys a ton. I'm going to take another look at it tonight and report back. :killerjob:

HogsRear
05-09-2016, 4:25 PM
69433

So I made a couple changes.
First, you'll notice the addition of two wires coming out of your generator- unless you've got a PMG generator (which I don't think the GS series ever did), you'll need to apply 12V to those wires in order to get AC power out.
Second, you'll notice the routing of wires out of your starter. The way you had it wired, the lights only would have been on when the starter was cranking.
I also added some fuses- the one out of the R/R is critical (ask me how I know...). It will protect the rest of the system in the event your R/R looses the ability to R or R. Either way, you'll end up on the side of the road, but with a fuse, you won't end up with a fried battery like I did. The fuse after the coils and excitation wires- that I added so if there was an issue with wiring elsewhere, for whatever reason, your bike would still run, and you could still get home (albeit without headlight or taillight).

Also, I'd definitely recommend going and getting a Mosfet R/R. Only one I've found that doesn't just blow up within a couple hundred miles. I ran a cb750 one; it fried. I ran the stock one; it fried, and took the battery and most of my electronics with it (unrectified AC will do that). The Mosfet has been going strong for 1200 miles.

Hey Westbound, so I just double checked and I do only have those three wires coming from my generator to my R/R like in the diagram below. Does that mean I do have a PMG generator? Not sure how that affects the diagram you modified.
http://i.imgur.com/xTWAJZQ.png?1

Westboundbiker
05-10-2016, 6:32 AM
Ok, must be either PMG or internally excited somehow.
In that case, you can just ignore the wires that I drew above the stator. I've attached a drawing removing those wires.
69547

HogsRear
05-10-2016, 11:22 AM
Ok, must be either PMG or internally excited somehow.
In that case, you can just ignore the wires that I drew above the stator. I've attached a drawing removing those wires.
69547

Cool, thanks again man that's super helpful. Will 20 amp fuses throughout work or should I use something else? Also, I have a stock, wet cell 12v battery but I'm looking to downsize and switch to gel type. Not trying to have a battery the size of a tic tac box, but something even slightly smaller than stock and able to be turned on it's side would be nice. Any recommendations?

47str8leg
05-10-2016, 11:53 AM
Only thing I can add to this thread is you don't need to use an "On/Off/On " switch they make "On/On" switches to change from low beam/high beam.

HogsRear
05-10-2016, 1:00 PM
Only thing I can add to this thread is you don't need to use an "On/Off/On " switch they make "On/On" switches to change from low beam/high beam.

Yeah, I just wanted a way to have the headlight off as well all in one switch.

Jasonisdico
05-10-2016, 4:57 PM
Only thing I can add to this thread is you don't need to use an "On/Off/On " switch they make "On/On" switches to change from low beam/high beam.

The bike is a kick also(I believe). So killing the headlight when kicking is a nice thing to have.

47str8leg
05-10-2016, 5:55 PM
The bike is a kick also(I believe). So killing the headlight when kicking is a nice thing to have.

That is accomplished by putting the brake lt only on your ignition position and the head and tail lt in the lights position. Then you don't have your headlight on while kicking.

Westboundbiker
05-10-2016, 7:08 PM
I'd put a 30 amp main, and run the others as 20s, you should be fine. And as far as the battery, just avoid lithiums, unless you like lighting shit on fire, or having a dead battery. If you try to charge one from low volts with anything but the balance charger, you're going to have a (fiery) bad time.

HogsRear
05-16-2016, 5:32 PM
I'd put a 30 amp main, and run the others as 20s, you should be fine. And as far as the battery, just avoid lithiums, unless you like lighting shit on fire, or having a dead battery. If you try to charge one from low volts with anything but the balance charger, you're going to have a (fiery) bad time.

Finally got it all wired up and............ nothing. I went through and double checked grounds and connections and everything seems right according to the diagram. My carbs are currently off the bike but I was hoping to at least test the lighting in the mean time but nothing is getting power it seems. My battery isn't brand new but it's alright enough to at least turn a light on. Any ideas? For the record I used crimps rather than soldering, but I don't think that matters.

Westboundbiker
05-16-2016, 6:28 PM
Do you have a multimeter? Start at the battery, and check for voltage at each fuse and connection point. It should show you where you're hung up.

HogsRear
05-17-2016, 5:44 AM
Do you have a multimeter? Start at the battery, and check for voltage at each fuse and connection point. It should show you where you're hung up.

Pulled out the multi-meter like you said, turns out my battery wasn't as charged as I thought. Hooked it up to my car battery and got the headlight to turn on for a second then it went out. Tried the momentary start just to see and it did engage the starter motor. Not sure if maybe the fuse blew up to the light, it was dark last by that time and I called it quits.

Westboundbiker
05-17-2016, 6:11 AM
Well, that sounds like progress to me! On every custom I've built, I've gone through one or two headlights and fuses before getting it all to work right, so you're on the right path, haha!

HogsRear
05-17-2016, 4:30 PM
Well, that sounds like progress to me! On every custom I've built, I've gone through one or two headlights and fuses before getting it all to work right, so you're on the right path, haha!

Baby steps are still steps as far as I'm concerned. Just checked and it was a blown fuse up to the headlight/accessories. After some quick googling it sounds like I have a short going on somewhere. Don't have time to dig in now, but fingers crossed it's an easy fix that just requires some electric tape.

HogsRear
05-18-2016, 8:28 PM
So it turns out the light switch I has mounted on the bars was shorting the circuit where the wires connected, blowing the front fuse. I didn't have the wires tapes up or anything yet so it makes sense. Pulled the switch off the bars, popped a new fuse in and I've got working lights! There are a few things I still have to finish up before I can really try starting it but this has been a huge help.

:cheersmate:

Westboundbiker
05-18-2016, 9:11 PM
Sweet! Glad I could help!