Starter/Electrical Issues

hippiedreads

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Some background. Bike is a 74 XS650 that hasn't ran in probably 10 or more years. I've got the bike mostly back together and am trying to start the bike for the first time. Previous owner said it started with starter fluid before tearing it apart and but who knows if that's true or not. Bikes does has good compression and I have done my own shorthand wiring to be minimalistic following some of the many diagrams found in this forum. Recently installed a pamco electronic ignition and pma charging system.

I have a good solid spark when kicking the motor over, I also have a good spark when using the starter motor (although I need to address the starter motor gear because it occasionally grinds it does still spark). I've cleaned the carbs really well twice and after kicking the bike a few times and pulling the plugs I can smell gas in the cylinders so fuel isn't the issue (clean fresh fuel supplied to the carbs).

Now I can kick and kick and kick with no avail. I can use the starter motor until the battery is drained and still no avail. Ive even hooked up a timing light to make sure the sparkplugs were sparking while everything connected.

But now the weird part, when I turn the key off inbetween these tries I'll get a backfire. Under more investigation I've noticed that if I cycle the key on and off it will spark the plugs. I've only done it a couple of times just to make sure that that's what actually was happening. This surge of voltage can not be good for the pamco and I'm wondering if it might be causing my no start situation. If anyone has had a similar problem or any suggestions I am open ears.
 
Are you using the choke?
When you cleaned the carbs twice, did you by any chance clean and confirm clear, the very small orifice in the bottom of the float bowls. That orifice must be clear, because that is where the extra fuel comes from when you choke the engine.
 
With choke and without choke. I've also squirted starter fluid in through the carbs and also through spark plug holes. I'm fairly certain on the carbs because I've read a bunch on this forum and have gone through the link to a PDF I've seen you post on here before.

I'm more interested in why the bike is sparking and backfiring. Also notable is that it only backfires when turning the key off and at no other time.
 
I wonder if you have the coils connected backwards (left side coil firing the right side cylinder...)?
 
Pamco ignition is a waste spark system with single coil, both plugs fire together, doesn't matter which wire goes on which plug. When in doubt, confirm the installation. If that checks out, do a search, there's plenty here on the subject. If that yields no joy, email Pamco Pete.
 
What do the spark plugs look like when you remove them.............................are they fouled with excessive gas?
When you cleaned the carbs, did you carefully set the floats to the correct level? Did you test the floats to be sure they are not leaking? No point in proceeding until you have the float levels set properly. You have too much gas entering the cylinders that is not being burned, so its fouling the spark plugs.

Don't be concerned about the odd back fire. You have gas/air vapours in the cylinders, so when you turn off the key, the magnetic field around the ignition coil collapses quickly and produces a spark. That shows that the Pamco is producing sparks, as it should do. The Pamco ignition is not your problem.
 
Have you played with the timing setting at all? I think the initial install position of the Pamco plate is centered on the adjustment slot, but that may not be exactly right. I would try it a little left and right of center to see if it fires up then. Once it's running, you will need to exactly time it using a timing light.
 
Thanks for all the replies guys. Ive double and triple checked the wiring to the pamco. I've adjusted the timing position on the pamco in every which direction possible to no avail.

As far as the carbs I've checked the floats and they seem to be working properly and there's no noticeable tears or damage to the rubber. I also dropped the circlip on both to one lower to add a little more fuel to the mixture in trying to get it to fire up. If the bike isn't running or hasn't run since I've owned it what is the easiest way to check timing?

I've marked by hand on the PMA my TDC and reinstalled the side cover to view my timing mark. I'm having a hard time holding the timing light, and jumping the starter motor all while watching the timing mark. So either I need an extra hand or wait until I have a friend to help.
 
You don't set timing to TDC, you set it about 15°BTDC. If you've got it set to (or near) TDC, that could be your problem right there.
 
I don't have it set to anything really. I've been playing with timing via the position of the pamco. I've marked TDC in order to do the timing of spark. And as said in my last post I'm not sure on what's the best way to find the timing while the bikes not running other than playing with the pamco and a timing light.
 
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What do the spark plugs look like when you remove them.............................are they fouled with excessive gas?
When you cleaned the carbs, did you carefully set the floats to the correct level? Did you test the floats to be sure they are not leaking? No point in proceeding until you have the float levels set properly. You have too much gas entering the cylinders that is not being burned, so its fouling the spark plugs.

Don't be concerned about the odd back fire. You have gas/air vapours in the cylinders, so when you turn off the key, the magnetic field around the ignition coil collapses quickly and produces a spark. That shows that the Pamco is producing sparks, as it should do. The Pamco ignition is not your problem.

Just to answer a few things. I guess I haven't gone checked my tolerances on my float when cleaning everything but I did make sure that it floats freely and it downs seem to have a ton of free play, less right at about the tolerance of 2mm id say. Spark plugs don't look fouled when I pull them.
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I'm leaning more towards it being timed incorrectly. The timing marks on the case are a little sloppy and I'm going to go online and size up one of the hughs stickers and print one myself. Hopefully this will help.

As far as the pamco though, the discharge of a spark after the key is cycled off is common? I'd think that'd be hard on the pamco's electrical unit?
 
Yes, it looks like your timing is not right. Its most important that you have TDC correctly identified. Use the SEARCH button in the upper right corner, and type in "TDC piston stop". That will give you a bunch of threads on how to find TDC.

What is hard on ignition systems, is leaving the key and kill switch ON when the engine is not running. If the engine rotary position just happens to stop where the ignition is in its dwell period, there will be full current flow through the coil, and a magnetic field around the coil. Turn the key on and off in this situation and a spark is produced. If the cylinders are full of gas/air mixture, then you can get a back fire. Some ignitions have a protection design to shut off the current, or not turn it on if the engine is not rotating.................the stock TCI and the Pamco E-advancer have protection circuits I believe.
 
Appreciate the advice, finding top dead center is pretty easy. I'm gonna clean up some of the sloppy marks. I've yet to notch the pma so it's not a big deal to do it still. The information on the pamco is great info, thank you. I'll get to attacking the issues tonight and keep you guys posted.
 
Okay, I'm sitting in front of the bike right now. The first picture is of the pma with TDC and 15 degrees marked in sharpie. I've colored my TDC in the picture with a blue and indicated the 15 with green. This is based on my first method of finding TDC with a screwdriver method, same way I checked and adjusted valve lash.

Second picture is of my pamco in the position where my TDC on my stator is best lined up with the 15 degree mark I've made on the case.

I've hooked everything up to a charged battery 12.8V and am using the starter motor and a timing light to try and get it all close. I know retiredgentleman has asked about the carbs and although I'm fairly certain it is not carbs I will do a triple check. Even with that being said, I've been spraying starter fluid through the carbs and into the head. This should get at least one cylinder to fire but it simply does not. The only time it does is after cycling the key off and it will occasionally back fire like stated before.

I've read many things on here about the cam chain but I've gone through the simple check of making sure the 3rd pin on the ignition set up is at 12 o'clock at TDC and the bike has relatively low miles so I don't think it's that.

I'm stumped as to why I can't get any type of life out of the motor when it appears everything is checking out... fuel/air/spark and timing is in the relative ballpark according to the thousand other posts out there on ignition.

EDIT: wiped clean the marks and did it over, while the line was close it wasn't quite where it is this go around. Topped off the carbs with fresh gas and gave it another whirl. Tried catching but wouldn't so I adjusted the pamco a little CCW and she fired up for the first time in god knows how many years. Thanks everyone for your input and especially retiredgentleman. I look forward to being able to help someone else through these same problems.
 

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