Electrical nightmare throttle only works properly at high RPMS

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Electricnightmare

XS650 Enthusiast
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so i blew up my xs11 and bought a 650 that "only had carbs issues" and needed a new battery. I know i was pretty green. So i clean the carbs and almost eliminate the back fire from the right cylinder. it persists but I'm excited so i whip it into town with the shit battery it dies my jumper pack dies we try my pals elscalade no luck. I get her home on the trailer get a new battery then ride 60 miles to go skydiving which made me feel pretty cool. bikes dead jumper pack ride it all the way home have to pop start at the gas station for the final ten minutes. I get home I go ok time to learn about charging systems. pop the headlight after checking curlys go to test and discover the tweaker PO re-wire massacre(photos tomorrow its getting dark out) not knowing what im getting into thinking everything is pretty much gonna be signals i plugged something into something else and shorted one of the wires running to the 6 way in my stator. knowing more now, its pretty strange it would have blown i think. a day or two later i rode into town about ten fifteeen minutes it worked fine. then after sitting for about an hour later i tried to ride home throttle bogged out tough and i could barely make it up the rolling hills home. Now it behaves like the mix is way lean throttle bog and dying out with gas. I messed with the idle mixture screws and tried to dial them and my idle in but it fluctuates. Sometimes it seems like the right cylinder sudden becomes electrified again and starts firing and throttle behaves normally. I know this from laser temp gunning my pipes at idle i was getting about 77* on the right cylinder and 126* on the left side clynder. suddenly something happend after i gave it gas to like 4000 rpms. Abrubtly the backfire stopped it only fell back to apprx. 2500rpms and i had to adjust idle back down. I thought it had fixed itself for a moment until it got back down to about 1500rpms when it lost spark again(i temp gunned the pipe again before adjusting idle back down left and right pipe were the same. I think this could be due to my regulator being wired into the system wrong only allowing the coil to get sufficient spark once the alternator is inputting a certain amount of charge.BUT why would that have happened since i returned all the wires to their "original" positions when the bike was previously running acceptably but without charge (well only about 2 volts) Tomorrow im also going to create a wiring diagram for my "custom " electric on my otherwise stock 79. If i dont theres no fucking way anyone is going to be able to help me. I want to drop the coin on a hughes and the new ignition system because im hoping it will simplify my problems by being forced to a chopper rewire which ill have to do because the rats nest is unacceptable and i dont understand wtf is going on. I began to try and map it out today but was overwhelmed by the assumed absurdity of my "current " wiring system. please ask me questions ill be on it idk what else to tell
 
 
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Hi Electricnightmare and welcome,
OK, your electrics are fucked. If you just throw a PMA & Pamco at the problem without knowing what's wrong your electrics will still be fucked and you'll be ~$500 poorer.
Your bike running OK when it's wide open but not otherwise tells me you didn't clean the carbs properly. Like totally apart except for the butterfly seals (because they are a right swine to do) and blow carb cleaner through each and every little jet, hole and passageway, mebbe 3 times over.
Back to the electrics. Go buy a new battery (or for statonary tests borrow the battery from your car or from your XS11 and connect it to the bike's battery leads with jumper cables) Now if the PO's wiring is truly FUBAR rip it all out of there.
Use that simple wiring diagram to hook up the ignition (nothing else for now, just the ignition) and (after you've cleaned the carbs again) try for a kickstart.
With the kickstart working and the engine starting and running OK, install your new fully charged battery, hook up the e-start wiring and see if that works.
Then hook up the lights. If you used the simplified wiring you will have bypassed the '79's auto-on headlight feature and the need for a working alternator to trigger it so your bike will be good to go until the battery goes flat.
Now you'll need to get the alternator working. Remember, everything works off the battery but it needs the alternator to keep it charged up or you'll only be good to go until the battery goes flat, like great-grandpa on his single-speed 1907 Clyno.
The alternator wiring will be just as shown on that simplified diagram, too.
Remember:- One system at a time. Take baby steps. Be patient, You'll be OK.
 
Hey thanks for getting back to me. I cleaned my carbs three times before I decided it was electric.additionally I put 180 miles on it then did some electrical repair( my stator wires had come loose and my nuetral light started flicking on and off from the chain. Then after my date when the bike started going out and bogging out to the point where the engine almost died was in conjunction with flickering display lights. Since then Ive cleaned the carbs 3 times so ive cleaned em like 5 time since i got it half way through may. but annnnnnyways I rewired it like this. Im 99% sure this is exact just whipped it together today. So ill clean my carbs again I know it SEEMS like lean fuel but idk. . .
1979 wiring.jpg
the question mark at the head light is because all my wires are black and i cant get electric to go into it proper. PO put a switch on the headlight houseing that the switch on there. Also my stator is has metal screws still but i checked resistance from the wires to the engine case and my readings are infinite. so i guess they arent ground to the frame?
 
yeah i wasnt going to get a PMA till i had it running with the simplified wiring. because IF I had picked it up and it didnt work Id have to do this anyways. But your sayin dont even hook chargin system up then? Just red wire to ignition to spark and point to condensor and sparks?
I have three wires in my key switch one red one blue and one brown. Ive got my brown led to the brown wires on my spark. Blue/yellow striped feeds into brown on reg/rec I have 4mm screws but my stator has all metal still. Im going to disconnect my charging and do DC readings and post again maybe i can get into town for carb cleaner tomorrow
 
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My test light illuminates for all my circuits If i make a jump from my negetive terminal this means i have a bad ground? I only have like fucking three head lights not even hooked up
 
Hi Electricnightmare,
I think what I'm saying is that as the battery runs the ignition, the lights and the starter and the alternator keeps the battery charged so there's four different electrical systems to get right.
I mean, my old BSA ran perfectly with just seven wires (OK, ten if you wanted signals) but the XS650's main wiring loom is thick as a fat man's thumb so it's better to work on the XS650's electrics one piece at a time so you don't drown in the details.
Especially if all it's got is black wires. What cruel PO would do that to a purchaser, eh?
 
yes i understand that. I disconnected everything else but power isnt flowing into my system. the test light only responds if i jump it to negetive terminal. I assume this means i have a bad ground. theres only two though and they seem fine. Seven wires sounds great to me. only the three wire connector from the back of the headlight to my switch is black. any Idea why electricity isnt running into my system when i switch my key? the ground for the system when isolated to ignition only becomes condensor the spark plugs and points correct? or do i need to make a jump to ground for flow to be drawn into the system? Thank you fredintoon
 
Ok lets start by throwing that tester you have in a corner and get a multi-meter. That tester you have can only show if you have electricity in a circuit, It can't tell if that electric is 11 volts or 12.5 volts. That can be enough difference between running and not running.
To properly test a lot of the charging components on an XS650 you need to test ohms, your test light can't do that either.
I agree, hook up a good battery to just the ignition, kick start to run. This allows you to tune the carbs with out charging system issues.
Once it runs ok, Hook up the charging system. In the 'Some Wiring Diagrams" thread, I like #4, It shows a basic points ignition with separate reg and rec. Hook up your stator to the reg and rec as shown in the diagram.
Use wires out of the stock harness to build the new one. This way you can use wires the same color as stock, this makes it easier for us to help you.
Testing the rotor and stator for proper ohms and for possible shorts is a good idea.
Your repair manual cover this, so does the Charging System Guide, so I won't rewrite them.
On the brushes the inner brush has a long mounting strap, it goes from the bottom screw up over the brush to another screw then turns left to go over under another screw. These three screws thread into the stator housing. This brush is grounded. It has a black wire that runs up into the harness and runs up to the regulator black wire. The other brush has a short mounting strap that just runs from the screw up over the brush. This is the hot brush. The regulator has a brown wire that goes to power after the main switch. The reg reads the voltage on this wire, If low the reg turns on the current flow through the rotor by sending battery power to the hot brush on a green wire. This make the alternator put out power.
On your headlight itself there are three prongs that wires hook to. If you hold the headlight right side up the prongs will have one horizontal prong at the top and the two verticle on the sides. The left verticle prong is the ground, the other verticle prong is high beam, the top prong is low beam.
Knowing this makes the wire colors not so important. On the headlight high /low switch power comes to the switch on the center prong, one of the other prongs is high beam the other low. Make sure the high from the switch hooks to the high on the bulb.
Good luck with your bike.
Leo
 
thank you xs leo! I have Isolated the ignition circuit and unplugged the charging system as fredintoon said. Buuuuut I switched to the test light to try and feel like I did something right. I also wasn't sure what voltage should be running though my system. As of now I have everything wired as it should be ( But i guess somehow i do not) but it is not sucking power into my system when the keyswitch is turned. This is extremely frustrating as its very little wiring and I possess elementary knowledge of Circuits. If I hot wire pass the key switch so power is feeding directly into the brown wires on my coils, I should have spark correct? I do not have my wiring like this now for fear of damaging things. I have the grey and orange from points fed into two two-to-one bullet spliters that runs to my coils and my condensor which, runs back into my coils, after power is fed from the brown wire from my key switch into the brown wires on my coils.Pheww. I guess what Im asking is what should my voltage be with the key switch off and then on, between my positive and my first 20amp and then before my coils after the keyswitch after the three way connector. Also If I were to hotwire past my key switch to the brown wires on my spark coils power should be constantly flowing into my system, correct? What should the Dc voltage read between battery and my 20amp fuse in this scenario? Would voltage only pass when spark fires, or is it constantly flowing into the system until the condensor "charges"?The only ground in the Ignition system is spark and condensor correct?If voltage is low what should i do to fix it. Ive been pulling my hair out because Ive followed my wiring diagram and believe its correct, so i dont understand why im not gettting spark. Ive tried with charging system connected and disconnect. Thank you for you help I hope my questions are coherant enough to help me quickly and easily. These are the missing pieces of the puzzle to as to why im confused by the circuit
 
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additionally if anyone would be down to have a brief phone conversation with me 10-15 min it would be greatly appriciated i feel like im very close but am mission due to lack of knowledge ALSO I belive I have a 79 650 F model and a solid state reg/rec from a later model. Also I just watched this video
Yahmaha tech training video and the section on CDI's has confused me do I even need to run power to coils If im going kick only?
 
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