Topic: inconsistent spark at #3

[LeoLegendATL]

Recently fired up my bike after a full maintence procedure, and found that 2 and 3 were not firing.  Traced this problem to a plate point screw coming in contact with the condenser wire.  Fixed that problem and now number 3 only wants to fire erratically.  I hooked the timing light up to it and saw it stobing only once every few seconds.  All other cylinders run ok.  I changed the plug and recapped the wire.  Any ideas? condenser maybe?

[Gordon]

Are you positive the spark plug isn't firing, or could it just be the that the strobe light isn't picking up a strong enough signal to light every time?

If you're sure it's not firing, pull the plug and clean it off.  Also, pull the cap off the wire and see if the end needs to be clipped off to get a better connection.  If the #2 is firing fine, but not #3, the problem isn't with the points or the coil.   

[bryanj]

If all four are running it has to be a bad strobe pickup.

[LeoLegendATL]

the plugs fires, just at weird times.  I tested the #2 with the stobe and fires great.  I switched the plug caps but nothing, maybe ill recheck the cap connection.

[Gordon]

I still wouldn't go by what the strobe light is doing.  It's not meant to be used as a diagnostic tool.  I've had the same thing happen with mine before when the plugs were firing just fine. 

Go by what the engine is doing.  Do you hear it misfiring?  It should be a fairly obvious stutter when it does. 

[LeoLegendATL]

Yes, it is misfiring, but yesterday I believe I figured it out.  I had the bike running and was messing with the plug wire around the coils and whenever I pushed the wire into the coil more, it started to fire.  When I let off, no spark.  Appears to be a bad connection.  I read the post in the FAQ about drilling and remounting a wire, any one have any luck with this?  I started to drill it yesterday, I just don't know what wires I need.

[dusterdude]

leo,find someone to sell you a length of mettalic core plug wire then find an ngk dealer and buy a plug wire splicer and put them together.worked well for me then i changed coils to a replaceable plug wire style.good luck

[LeoLegendATL]

thanks a bunch, which coils have the replacable wires? gl100? cb900?

[dusterdude]

i believe anything in the late 70`s and on,mine happened to come off some kind of yamaha.work fine no problems so far

[eldar]

78 does not have replaceable wires. That started on the 79s.

[dusterdude]

yea,yea,yea,gee some people are so picky.isnt that right oh god of k8 misfire.

[bryanj]

NOT gl1000, they are "ballasted" coils I am told 750/900 DOHC will fit but current draw will be higher so contact life shorter

[dusterdude]

bryan,they are probably 3 ohm coils,as are the yamaha coils i put on my bike.

[eldar]

I think the 79s on are 3 ohm. So sayeth the K8 god!

[LeoLegendATL]

thanks for all the help you guys.  I finally found the problem after buying new coils on ebay, the same problem was happening, crappy #3.  So I decided to take the carb apart, and what do ya know, the slow is sitting in the bottom of the float bowl, whoopee!  props to gordon on the timing light not being a diag tool, the gas was fouling the plug and no spark indeed.  Not to mention it ran like crap.  So tonight I did a carb sync and decided to go for a night ride to the shop where I work and just sleep there till morning.  Ahh it's 2 am what a great ride though!!

[dusterdude]

dont it always seem to be something stupid