Coil question

If that's the charger with the starting circuit don't use that part of it. Not sure what the result would be, but the battery is meant to charge at 2A or less but the starter makes about 50A available. You should be getting plenty of power already with what you describe.

The last time mine would just "backfire" and not start, the pickup coil was bad - one coil was open. Put on my spare one and off I went. It can only be a few things, two of which you can only test by substitution.
 
If that's the charger with the starting circuit don't use that part of it. Not sure what the result would be, but the battery is meant to charge at 2A or less but the starter makes about 50A available. You should be getting plenty of power already with what you describe.

The last time mine would just "backfire" and not start, the pickup coil was bad - one coil was open. Put on my spare one and off I went. It can only be a few things, two of which you can only test by substitution.

Ack.... Is the 'pick up' coil different than the ignition coil? Cuz i already replaced that one already and I'm in the same shape.
 
^no need to swap the pickup coil to test. Not easy to swap it either. Just unplug it under the left side cover (find the three wire connector) and measure the male side; should be around 700 ohms from the gray wire to black and from orange to black.
 
Ok. Sick kids today kept m out of the garage. I got new batteries for the multimeter and will get out there tomorrow. Those two bundles of wires travel so close to the chain... I wonder if they might not have been eaten (since when I rebuilt, I put them in the way I thought the should go).
 
went out today with the intention of FINALLY figuring this out.

First checked the ohms on the pick up coil and it was perfect both sides. Then wiggled every electrical connector I could see because, you know, that fixes things, right? Then turned it over but it was just a quick burst of running and hitting the throttle made it die.

So, I put the batter on my HF charger and quick charged it in about 5 mintues. Measured 12.6v across the battery and tried again, but it just lugged!

So, figuring this had NO chance of working, I kicked it and it started right up!!! vroom vroom and everything!!
lots of exhaust and i could see I'd forgotten to tighten the right exhaust where it goes into the block.

Now, what the heck was wrong?!?! Is my NEW battery bad despite being charged and measuring 12.6v?

Actually, you know what made it go? I just sent a guy $80 this morning by paypal for a working TCI module he has. Apparently I should have done that to begin with!
 
Your battery's not the problem at least judging by what you've said. Hard starting and dying as soon as you rev could possibly be the choke or lean carbs. Among other things.

Good to have a spare TCI with you, even if you never need it. $80 isn't a bad deal. Try it out when you first get it, then keep it in storage. No need to mount it - just plug it in and let it hang.

You mentioned a loose head pipe. When I put a replacement stock exhaust on mine it ran weird for a few minutes, and might have been hard to start, can't remember. While it was idling it slowly fixed itself over the course of maybe ten minutes. It was weird. I guess it was the donut sealing down or something.
 
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12.6 volts is not fully charged battery. fully charged battery voltage is 13.2 Volts. What type of battery? Wet cell? AGM?

It's the kind that doesn't get water added, came fully charged from batteries plus, and cost about $70, twice one of the regular wet cell.
 
Your battery's not the problem at least judging by what you've said. Hard starting and dying as soon as you rev could possibly be the choke or lean carbs. Among other things.

Good to have a spare TCI with you, even if you never need it. $80 isn't a bad deal. Try it out when you first get it, then keep it in storage. No need to mount it - just plug it in and let it hang.

You mentioned a loose head pipe. When I put a replacement stock exhaust on mine it ran weird for a few minutes, and might have been hard to start, can't remember. While it was idling it slowly fixed itself over the course of maybe ten minutes. It was weird. I guess it was the donut sealing down or something.

Hmmmm. Dunno. Tci is now the only thing in the chain I haven't checked so, yeah, it'll be good to see what, if anything is better or not.
 
^You haven't checked the igntion coil by substitution yet, have you?

If that's not the problem, it's good to have a spare coil on you as well :)

If you start to suspect the choke, then if it's hard to start but after it warms up it's easy to start, that points toward the choke. Could be lots of things right now. Not enough detailed organized information.
 
I swapped he coil. Sorry not enough detail. Seems I've now taken apart and/or wiggled just about everything takeapartable or wigglable. I was chicken to use the start function on my new charger... But it seems increasingly that the issue is electrical and I'm starting to believe seriously it won't be anything specific.
 
I'm starting to believe seriously it won't be anything specific.

Oh, it's specifically something. So, when you got it started, did you turn it off and try to start it again? Was it easy to start warm? You need to characterize the problem better.
 
i did turn it off and restart it. However, at this point I had none of the airboxes back on, and the tank was sitting over where the seat would be but backwards because I don't have anything fancier to supply fuel while working on it. Basically, I'm not ready to say I've figured it out 100% yet, but I think I may have it working.

Here's the scoop: I got the bike up on the table originally to troubleshoot the RHcover leak since I rebuilt the whole engine. I also had a starter issue caused by my forgetting part 21 in this diagram

Upon buttoning everything up, I first noticed it wouldn't crank over. It's never done that before. It was acting like either the battery had totally died, or I'd forgotten to remove the corks I put in the exhaust ports to keep valves clean while I had the pipes off.

I thought: battery. Got a new battery (AGM type). cranked a little better but wouldn't fire, and I still couldn't kick it either. Then, while kicking it, dumped the whole damn thing over into my wife's bike, slicing my seat with her license plate. righted it. walked away.

I thought it might be flooding because plugs were wet. First checked for spark which was there, although seemed weak (but I don't know if I'm a good judge of that). Got new plugs, still wouldn't start. Did get a few backfires. Took off carbs (although I'd done that in the spring and they were clean then). They looked fine, but I still shot carb clean through all the bowl channels and choke parts. Got new gaskets for the bowls and new bowl plugs because one was leaking. Still same symptom.

Replaced coil with the black one from Mikes. Now would fire every few tries, but just sounds like it's still having trouble turning over. Took off RH cover to try and find out why it's leaking oil. Found it to have slightly not flat lower lip so it wasn't sitting flush with the engine and gasket. walked away.

I did notice that I could BARELY turn the tach gear. Actually, tach gear was probably ok, but the worm drive (rod that turns the tach cable) was really really stiff (and not the good kind). I had another known-to-be-good RH cover that I put on instead with a new gasket.

Now it turns over easier, occasionally backfires, and rarely really fires. Walked away.

Mind you, I have the trickle charger on all the time I'm not there and I come back to a green light on it.

Today I took off the LH cover to check the pick up coil wires as suggested above. Wires appeared ok, and I had good ohms when I checked the wires at the plastic attachment at the end of the wires. But while I was there, I wiggled everything. I looked for the TCI and noticed it seems to be nearly inaccessible without pulling the whole battery box apparatus. So, I just really wiggled everything with a connection and made sure there were no loose wires anywhere.

Then, I put the new HF charger on the battery until it said it was charged (although it only measured 12.6v and I see that it's supposed to say 13 somthing). It was trying to fire. I kicked it and it started. It stalled when I gave it gas. Tried a few more times w/ electric start and got it for a sec but then it'd stall when I gave it gas. Then, I got lucky (not the good kind) and kicked it into running. Ran and ran and ran until I was in a growing cloud of exhaust (a little more than I remember it spitting forth, but it's usually running down the street, not sitting still in my garage). Turned choke off, watched it idle. vroomed it a few times. That's when I noticed the right pipe was loose at the cylinder.

So, that's that. Right now I've got everything buttoned back up except that I can't get the hose to stop leaking where it hooks into the right petcock for some reason... even with a new piece of hose. I'll get a little hose clamp tomorrow after work and will see if it wants to start up.
 
Your new battery could be part of the problem. Charge it up, take it back and have them load test it. If weak get them to give you a replacement, load test thast one too. Once you get a good battery, clean every connection between the battery and starter as well as the grounds.
As you crank the starter the battery voltage will drop drasticly. It can drop as low as 9 volts.
Most ignitions don't like low voltage much. The stock TCI is very voltage sensitive.
A poor ground will cause the voltage to drop even more. You need good clean metal to metal contact from the stasrter housing to engine, from engine to at least one engine mount. If the top mount, between all the parts of the mount too, from the mount to the frame. I suggest the rear mount, the mount is just two pieces bolted to each side of the frame and engine. Remove the paint around the bolt holes of the frame, around the holes in the mount plates. A bit of grease to prevent rust, bolt it all back together. The battery ground cable, both where it bolts to the battery and frame, clean metal to metal contact.
Same with the positive side. Clean connections at the battery starter relay and starter.
Heavier gauge cables carry more current with less voltage drop than lighter. I think the stock cables are 8 ga cable. Going to a 6 or 4 ga cable from battery to ground as well as to starter relay and from the relay down to the startercan help too.
When you kick start the bike, no voltage drop from cranking the starter, so full voltage to the ignition, starts up and runs fine.
Once you do get it running check battery voltage, if low your charging system may need work.
Leo
 
Update: success!

What fixed it? Honestly I don't know, but you guys sure taught me a lot about troubleshooting my xs650. I feel a lot less lost about where to start with issues like this now.

So, to summarize: it wouldn't fire. It wasn't the plugs, but now I have a new plug tester and a big box of replacement plugs. It wasn't the pick up coil and now I know how to test that component. It wasn't fuel supply. It wasn't the coil but now I have a new fancy black one and know how to attach ignition wires. It wasn't the carbs but now I've gone though them twice since getting this bike a year ago and... They're still really clean. It wasn't a loose timing chain or valves but now I feel confident about that procedure. It may have be the battery but that doesn't exactly explain everything because it was still having issues after I got a new one. I probably had something to do with the stuck tachy gear, and in figuring that out figured out the RH cover wasn't straight causing a leak.

So... Long story, lots of frustration, but I think I'm back in biz!
 
I just went through a lot of stuff with my ignition, and wrote up a short synopsis of testing the TCI ignition system.... spark, coil, pickup coils and tci. Link

Sounds like you got it sussed out, after a lot of frustration, but, it IS how we "teach" ourselves sometimes!!

:bike:
 
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