lost spark 1and 2

[TopCatGr58]

Test coils for ohm value.

IF they are 1.5 ohm, then yes, the B.R. could be bad/going bad. IF the coils are 3.0 ohm style....then the B.R. may be good, but it's NOT NEEDED if the coils are 3 ohm...and actually causes problems=low voltage if left in the circuit, it also causes ~4.5 ohms to be seen by the TCI...which won't hurt it, but is too much/not needed...just need 3 ohms....so either with 1.5 B.R. and 1.5 coils....OR just 3.0 coils and no B.R.

T.C.

[Eastcoaster]

Thanks TC is there a tech tip on the test procedure I have a multi meter
Do you remove the wires and test the 2 small + - posts ? key on or off I am so bad with this

[Eastcoaster]

OK think I got it remove wires from posts check with meter mine is old gauge X1K X10 I can pick up a digital tomorrow and get readings
Thanks I will keep you posted thank for pointing me in the right direction

[Eastcoaster]

TC
Its all making sense now on your past post I have a good route to go and troubleshoot this problem

1 check coil oms
2 if 1.5 need BR if 3 bypass it
if 1.5 check resistance on BR if bad replace
3 make sure 12v coming into BR
4 if less than 12 v start to work back

[cajun31]

East

TC is giving you great information, however I have to ask a question. How long has the bike been running fine before this problem? The reason I ask is I don't want to see you chasing your tail over a ballast resistor unless indeed the BR is bad. What is strange is as you stated you have lost spark on 1 and 2 which means both coils are acting up not just one. I would spend some time checking to make sure your not simply experiencing a loose or corroded/oxidized connection somewhere. A good cleaning of all connections along your wiring harness may resolve your issues. If you have a Radio shack nearby invest in a can of Caig Deoxit and clean and check all your connections. Lost smoke i.e. voltage or the system not charging properly can cause issues on these old bikes. Doing the cleaning / check is a good investment. If the problem still exists then you could start more in depth troubleshooting of components.

[BA80]

JAT.......check the plug wire/resistor cap connections. Also, look for a kink in the fuel line going to the #1 & 2 carbs. They are fed by the same line.

[TopCatGr58]

The wires I'm talking about are the harness power and ground wires, not the HIGH TENSION Spark plug leads/wires. And yes, measure across the terminal connectors thru the coil while NOT connected to the harness.

You can also check the Secondary resistance as well.. thru the plug ends one plug end to the other. First with the caps on.... then notate and then remove caps and measure again. Since these are aftermarket it's hard to say, but without the caps should still be around 15 k ohms. Check the caps also...if OEM, then should be about 5 kohm. There's a resistor inside and can get corroded as well...and so if much higher than 5-7 k ohms....then the caps or resistors may be bad/corroded. The caps can be taken apart, resistor contacts cleaned, rechecked....resistor can go bad also. IF running resistor plugs...then don't really need resistor caps...can put small SPRING or piece of thick gauge copper wire into cap to replace resistor.







Also, as stated check the wire to cap connection....if corroded like above can also cause loss of spark due to resistance!

T.C.

[Eastcoaster]

The Numbers

1 check coil oms COIL OMS 1.5
2 if 1.5 need BR if 3 bypass it
if 1.5 check resistance on BR if bad replace BR 1.5
3 make sure 12v coming into BR 11.17 volts to BR (Batt 12.2)

4 if less than 12 v start to work back Looks like this is the cause!

Clean all connections try to get 12 volts at BR and keep a watch on the BR if the oms go up replace Right now all are sparking

Thank you I learned a lot about xs ignition with this I will report back

Any specific thoughts on the power drop I already did TC's fuse box?
__________________

[TopCatGr58]

Good work so far!

As stated power to the B.R. comes from the TCI while running, but is bypassed during the starting mode. But it does look like you have a little magic smoke leak somewhere. Remove the connector to the TCI, clean the contacts on the harness and the TCI and reconnect.

A common suggestion has been to check the main ignition switch as well as the emergency shut off switch...take apart, clean, etc.! Check the voltages as you go to see where it's equal to the battery and where it drops off. Clean the connectors to the BR at the harness also, and recheck with voltmeter.

You say it's hitting on all 4 again, so just removing connectors probably caused enough friction to clean them a little...get some DEOXIT and really get them clean.

T.C.

[Eastcoaster]

Good Shape

Cleaned every connection freshened up the battery less than .01 between battery and ballast resister New plugs just back from a nice ride all is well

Thank you for the help I learned a lot

[cajun31]

Do you know

what was causing the problem? Good to hear you are back on the road.

[TopCatGr58]

Hey there Cajun,

You were right on the track, bad connections causing voltage drops....and then combined with the additional voltage drop that the B.R. causes, it was just too low so only enough juice to fire 1 plug on each coil! IT's rare, but have seen it reported before with this same cause/effect. Cleaning his connections got all the magic smoke to get to the coils and has power to fire both plugs now on each one!

Glad you got it fixed, "TEAM EFFORT" here on channel 11!

T.C.

[cajun31]

Thanks for

the update TC. I am always curious as to what pinpointed the problem. Makes it easier to troubleshoot down the road.

[Eastcoaster]

Yes best I can tell voltage drop at the ballast resistor I have put 200 miles on with no problems I cleaned everything you described and every connection I could find including the kill switch on the handle bar inside the light and the key switch. The voltage jumped within .001 of the voltage right off the battery. I also put new plugs in case I fouled them with the loss of spark. I learned an amazing amount of information from this thread and have a bike that runs beautifully.
Thank you for all you do

[cajun31]

Thanks

for the update Gordon. Glad to hear you are enjoying the bike again.