82 XS650 Starts then dies

[Michaelo]

Ok so you did 2M's test, when you say "it is ignition 100%" can you please elaborate, we're a little bit slow downunder....

1/ you did the test and it was 100% correct?

2/ the ignition system is working 100% ?

 

[Cal Schilling]

Ok so you did 2M's test, when you say "it is ignition 100%" can you please elaborate, we're a little bit slow downunder....

1/ you did the test and it was 100% correct?

2/ the ignition system is working 100% ?

Sorry for the confusion I am in the garage and not thinking about what I am typing The problem is the ignition 100% I did 2M's test and that determined that the ignition is a fault right now. I even bought some carbs off a guy a town over who took them off a working bike to help verify. Now I have two sets of carbs! So now I have to trace electrical problems.

 

[Cal Schilling]

Being an '82, I think you have all the extra safety relays. In particular, I think you have one on the sidestand. It will kill the motor if you put the bike in gear with the stand down. Maybe it's acting up? I think it's pretty easy to bypass, just unplug and jumper the wires together. Someone who knows more about it will hopefully chime in here.

5twins I tripped the switch and un-tripped the switch and the bike performs just as it did before. Basically switch is not the problem. But thanks for the input.

 

[Cal Schilling]

So i am back at it again. And I was determined to check everything I could today for electrical and using the manual I just started down the troubleshoot guide section and I got to:

"4. Rotor coil inspection: measure the resistance between the green and brown leads going to the alternator. The readings should be 5-7 ohms. Set the ohmmeter on its highest scale and measure the resistance between rotor leads and the rotor core (ground). The readings should be infinite. If either reading is incorrect, install a new rotor."

Well I check the resistance between green and brown and its 33.2Ohms so first red flag in my mind. I go to check the rotor leads to the rotor core and I am slightly guessing that is the green and brown to ground and the resistance is around 175Ohms. So according to this I need a new rotor.

 

[retiredgentleman]

Did you do those measurements with the green and brown still plugged into the harness?
The best way to measure, is to remove the 2 brushes. Measure by touching the meter leads to the two copper slip rings
Look for 5 to 6 ohms.
Measure from one of the copper slip rings to the rotor steel frame. Use a high scale. Look for a very high reading.
Also measure the length of the brushes...................replace if less than 0.4 inches.

 

[Cal Schilling]

OK I did what you asked and the resistance is 5 ohms between slip rings. But I am not getting a reading between slip ring and the steel frame I have the ohm meter set to the highest and I am not getting a reading between the ring and the steel frame.

 

[retiredgentleman]

OK I did what you asked and the resistance is 5 ohms between slip rings. But I am not getting a reading between slip ring and the steel frame I have the ohm meter set to the highest and I am not getting a reading between the ring and the steel frame.

Connect the 2 meter leads together and see what the resistance of the leads are (use the lowest scale). If as an example the leads measure 0.5 ohms, then the true reading of the rotor is 4.5 ohms, which is on the low side.
Not getting a reading is a good thing. It should be very high as 200k ohms or higher i.e. infinity or open circuit.

 

[Cal Schilling]

When I hook them together I get a 0 which to me means no resistance through the lead, because unconnected I get a reading of 1. So 5 between the slip rings and infinity on the slip ring.

 

[retiredgentleman]

You have a good rotor!

 

[fredintoon]

When I hook them together I get a 0 which to me means no resistance through the lead, because unconnected I get a reading of 1. So 5 between the slip rings and infinity on the slip ring.

Hi Cal,
the rotor resistance numbers you quote are just about perfect.
However, if you are still only getting a 5 second engine run every start I doubt you'll know whether or not the alternator is charging the battery.
But you seem to be sidetracking the brief run-time diagnosis.
Even if the charging system isn't working at all the battery (any battery; there's posts about getting an XS650 back home with a lawn tractor battery bunjied onto the pillion seat) is still able to crank the engine and keep it running until the battery voltage drops to mebbe 10.5Volts or the bike runs out of gas, whichever happens first.
Your carb swap and running on prime have already just about eliminated fuel supply being the problem.
You gotta concentrate on exorcising your ignition Gremlin.

 

[Cal Schilling]

I am thinking that I might be off on my timing by about a degree or two because I am not really sure where else to look at with this and you say ignition gremlin but do you have any idea where I should start?

 

[fredintoon]

I am thinking that I might be off on my timing by about a degree or two because I am not really sure where else to look at with this and you say ignition gremlin but do you have any idea where I should start?

Hi Cal,
if the ignition timing is off by a degree or so that'd make it run less well but there's no effin' way it'd let the bike fire up, run for a few seconds and then quit.
How to find the Gremlin?
First thing I'd try is to pull apart every single last one of the wiring that runs the ignition, clean and check that every connector is good then check every wire to see it's conductor wires ain't broken inside the insulation.
Then I'd try swapping each ignition component in turn with a known good one.
The hard part here is to find someone with an '80+ XS650 that runs good and who is willing to help.

 

[Cal Schilling]

fredintoon,

I am going to start with the cleaning of every connection first... EVERY DAMN ONE OF THEM!!! Thanks

 

[Cal Schilling]

Well lets continue this story. I cleaned every connection on the bike the best I can and I hooked everything back up I am right where I was before. I think I need to find another xs650 that runs and try to swap parts out next.

 

[figure8]

That's an expensive way to fix a bike! If you buy a running xs wouldn't you want to leave it alone and ride it?

 

[Cal Schilling]

That's an expensive way to fix a bike! If you buy a running xs wouldn't you want to leave it alone and ride it?

Well if the damn head didn't crack and I didn't go to gradschool it probably wouldn't be such a headache and I would be riding it. But since I am at this stage of the repair I would like to either see it through and get this pain in the ass bike running again or sell it to someone who appreciates it and knows how to fix it, and who will also pay me a fair price for it.

 

[TwoManyXS1Bs]

Well, Cal, guess it's time to familiarize yourself with the TCI.

Have a look in here:

http://www.xs650.com/threads/tci-box-a-successful-repair-electronic-ignition-ignitor.3289/

And, breeze thru the threads with 'TCI' in the thread title. There's a bunch, including many ads simply looking for replacements...

 

[peanut]

this is a crazy thread. i tried my best to work my way through all of it but gave up.

Unless there is a bad ground connection ,flat battery or direct short associated with the rotor/stator /regulator/rectifier ...the engine dying problem has nothing whatsoever to do with the charging system.!

The engine will will start and probably run for an hour or more just on a fully charged battery alone without any charging system connected.!

Sounds like you've tried just about everything without success but I didn't see the obvious tests for fuel air and spark.


When the engine dies
1. Does it just cut out whilst sitting at idle ?
2. or does it die when you try and rev the engine ?

Immediately after it cuts out and won't restart , have you checked to see that .....
1. you still have a stong spark at both spark plugs ?
2. there is evidence of fuel on the spark plugs and in fuel bowls?

if you fit some spark testers , when you try to restart the engine after it dies you will be able to monitor and see if your engine has still got HT spark to the plugs. They only cost a couple of bucks http://www.ebay.com/itm/Auto-Engine...:g:E-gAAOSw4hdXHuto&item=282017452157&vxp=mtr

The other vital check to make after the engine dies is to undo the fuel bowl drain plugs and check if they have any fuel left in them.

These two simple tests will establish whether the issue is electrical or fuel related

 

[Cal Schilling]

TwoManyXS1Bs I was looking at this last night and thought about checking it out. So far I have found one 12,000ohm resistor that only was providing 5,400ohms. And I found something labeled Z which is red and looks like a diode which seems to be corroded or burnt not 100% and trying to figure out what it is. I will edit this post when I figure it out. Update: it is a Zener Diode that seems to be corroded. If anyone knows how to identify it besides having a 2B on the outside of the diode I am not sure how to figure out what to buy for this diode. I will take to the internet but if anyone else can identify that would be helpful.

I have decent soldering skills so I will be replacing. And If I find a schematic for it I might build a second just for "fun"

this is a crazy thread. i tried my best to work my way through all of it but gave up.
Unless there is a bad ground connection or direct short associated with the rotor/stator /regulator/rectifier ...the engine dying problem has nothing whatsoever to do with the charging system.!
The engine will will start and probably run for an hour or more just on a fully charged battery alone without any charging system connected.!

Sounds like you've tried just about everything without success but I didn't see the obvious tests for fuel air and spark.


When the engine dies
1. Does it just cut out whilst sitting at idle ?
2. or does it die when you try and rev the engine ?

Immediately after it cuts out and won't restart , have you checked to see that .....
1. you still have a stong spark at both spark plugs ?
2. there is evidence of fuel on the spark plugs and in fuel bowls?

if you fit some spark testers , when you try to restart the engine after it dies you will be able to monitor and see if your engine has still got HT spark to the plugs. They only cost a couple of bucks http://www.ebay.com/itm/Auto-Engine...:g:E-gAAOSw4hdXHuto&item=282017452157&vxp=mtr

The other vital check to make after the engine dies is to undo the fuel bowl drain plugs and check if they have any fuel left in them.

These two simple tests will establish whether the issue is electrical or fuel related

Yeah this thread has gotten out of control but let me quickly bring you up to speed the best I can by answering all of your questions.

"When the engine dies"
1.) The engine doesn't even make it to idle. It starts and dies please see

adding choke just does the same thing at a higher RPM.
2.) If I rev the engine it dies in the same amount of time as in the video.

"Immediately after it cuts out and won't restart, have you checked to see that...."
1.) It will restart immediately after dying on me and I have a spark tester and I see a nice light every fire
2.) I am not sure about fuel on the spark plugs I didn't pull them out between fires but the bowls are full and as I said before it will fire/die again right after.

 

[Paul Sutton]

Wild, very wild guess, in fact clutching at straws - I have seen similar behaviour recently. If you have a strobe light hook it up and get someone to aim it at the timing plate. Start the engine and in that brief second or two of idle see if the timing is way out i.e. near the letter T and the TDC markings on the right. Heavily retarded timing will give those short running times before dying.

I hope things are resolved very soon for you.