Starting Problems, am I doing this right?

[TylerM]

Hi everyone, I just spent the past three months working on my carbs on my 1981 GS550L and ensuring they were squeaky clean. I've gotten to the point where there is nothing more I can do with them and the bike still won't start. This is leading me to believe that the igniter is causing my issues. I checked the coils with a multimeter and the resistance was within spec for the left coil (cylinders 1&4) but I couldn't get a reading at all for the right one (cylinder 2&3). When I checked for spark, I got nothing with 2&3 and a horrible, tiny spark for 1&4. I ordered Dyna green 3 ohm coils to replace both of them along with some new wires, and I plan on looking in to doing the relay mod to add more power to the coils

Here are the symptions I was having when the bike was running. When it would start (not often) it would huff and puff until it eventually fired. It took probably ten seconds from pressing the starter button to when the bike actually started running, gradually increasing turn over speed. When I would give it throttle, the rpms would drop (possibly a float level problem, but I haven't been able to start the bike to test that now that the floats are adjusted properly). After about a minute, regardless of what I did (choke, no choke, throttle, no throttle) the bike would die. It would just drop in rpm until it clicked itself off. Trying to start it back up would yield no results.

Are any of these symptoms leading anyone to believe I have a bad igniter unit? Also, is the igniter unit the same thing as the cdi or are they different? I see everyone talking about the cdi but I can't find any info on the cdi for my bike, and I'm lead to believe the cdi is the same as the igniter unit. That may be a noob question but I want to make sure I'm understanding everything about the electrical system of my bike (still new to the electronics side). If it's possible the symptoms are revealing a bad igniter unit, I will switch it out for a Dyna S ignition system, which would allow me to discard the igniter unit altogether, right?

I appreciate any help you guys can offer. Like I said, I'm very new to electrical work and only have a slight clue of what I'm about to get myself into. I just want to make sure I'm heading in the right direction before I drop a couple hundred bucks to replace my ignition system.

 

[chuck hahn]

Probably more the coils than ignitor seeing that 1 and 4 are hot. Got all connections cleaned and secure???

 

[TylerM]

Probably more the coils than ignitor seeing that 1 and 4 are hot. Does the bike have points? Maybe has a burnt set of points..which will stop spark to whatever coil the offending point bis connected to.

I'm not entirely sure what points are, but it's a 1981 and my service manual says says it has a Kokusan transistorized (breakerless) ignition system. I think this means I don't have points?

 

[chuck hahn]

yeah...i went back and reread the post and edited mine appropriately. Didnt see the year of the bike first time.

 

[TylerM]

yeah...i went back and reread the post and edited mine appropriately. Didnt see the year of the bike first time.

I haven't cleaned the connections yet but it's on my to-do list. I forgot to mention, I tested the igniter unit per the manual (bypassing the signal generator and trying to get spark from the plugs with a 1.5V battery) and was unable to get anything. That wouldn't work with bad coils, right? So the results of that test are only indicative of the igniter unit if the coils are known to be in good shape?

 

[chuck hahn]

Better yet...type in coil relay mod in the search box and read the many threads on this. Posplyr has many excellent posts and lots of great electrical experience.

http://www.thegsresources.com/_foru...t-hacking-up-harness&highlight=coil+relay+mod

 

[tom203]

Clean all the connections from signal generator coils up to ignitor and on to ignition coils, have you seen this testing procedure?

http://members.dslextreme.com/users/storagecliff/images/electrical_odd-n-ends.html#A17

the 550 ignitor seems the most problematic . It could just fail to spark 2and3,but do matchless testing before condemning it.

 

[TylerM]

Clean all the connections from signal generator coils up to ignitor and on to ignition coils, have you seen this testing procedure?

http://members.dslextreme.com/users/storagecliff/images/electrical_odd-n-ends.html#A17

the 550 ignitor seems the most problematic . It could just fail to spark 2and3,but do matchless testing before condemning it.

I have seen that. Could you possibly explain exactly how to accomplish #7? Am I supposed to measure voltage from the male end or female end of the connector? Does the ignition need to be on? Or do I have to be pressing the starter button? Because each time I tried to measure it I get a reading of 0V, and I know I'm not doing something right.

 

[tom203]

I have seen that. Could you possibly explain exactly how to accomplish #7? /QUOTE]
With ignition on and kill switch in "run" ,the orange/white wire sends 12 volts positive to both ignition coils- put one meter probe on this o/w wire connector and other probe on good ground.This o/w wire feeds the ignitor also a bit downstream thru a connector. The ignitor then "waits" for a pulse from signal coils, then suddenly grounds out the correct ignition coil which causes the two spark plugs on that coil to spark.Some of these ignitors don't tolerate much voltage drop ( say less than 11.5 volts) and that's why lots of folks do the coil relay mod.

 

[TylerM]

I have seen that. Could you possibly explain exactly how to accomplish #7? /QUOTE]
With ignition on and kill switch in "run" ,the orange/white wire sends 12 volts positive to both ignition coils- put one meter probe on this o/w wire connector and other probe on good ground.This o/w wire feeds the ignitor also a bit downstream thru a connector. The ignitor then "waits" for a pulse from signal coils, then suddenly grounds out the correct ignition coil which causes the two spark plugs on that coil to spark.Some of these ignitors don't tolerate much voltage drop ( say less than 11.5 volts) and that's why lots of folks do the coil relay mod.

Ok, thanks. I will retry to test for a voltage there and see if I can get anything. If the voltage isn't high enough going to the ignitor, should I look into wiring the relay to the igniter? Or will it work out anyway if I stick to wiring it to the coils?

 

[posplayr]

I have seen that. Could you possibly explain exactly how to accomplish #7? /QUOTE]
With ignition on and kill switch in "run" ,the orange/white wire sends 12 volts positive to both ignition coils- put one meter probe on this o/w wire connector and other probe on good ground.This o/w wire feeds the ignitor also a bit downstream thru a connector. The ignitor then "waits" for a pulse from signal coils, then suddenly grounds out the correct ignition coil which causes the two spark plugs on that coil to spark.Some of these ignitors don't tolerate much voltage drop ( say less than 11.5 volts) and that's why lots of folks do the coil relay mod.

The coils spark when the magnetic field collapses. That occurs when the coil current drops to zero. Coil(-) is near ground when current is flowing(getting ready to spark). Coil(-) climbs to +12V when the points/ignitor opens killing the current. That is when the spark occurs.