82 850 ignition issues.

[stoy75]

Ok so here goes. I have an 82 gs850glz. The bike runs and idle what seems fine but runs horrible on the highway. It bogs and surges and bogged till it died today on the highway and would only restart with choke. Removing plug wires 1 2 and 4 will change the idle and kill the bike. Plug wire 3 being pulled has little change if any. Carbs were stripped and dipped twice replacing all o rings. New intake boots. Sealed airbox. I'm getting despetrate here. Please help.

[Redman]

Your plug cap pulling testing is good idea, but doesnt tell you everything.

Pulling #3 cap and it not making much difference causes you to suspect sometimg with #3, but doesnt tell you if problem is ignition related or fuel related.

Do you know about pulling out the sparkplug and laying it on head (or otherwize grounding the sparkplug) and looking at the spark...? Then will have better idea if that plug is sparking. If its not, try swapping it with another one to see if problem is the sparkplug itself.

Also keep in mind that the sparkplug caps can go bad. They just twist pull off the wire, and new ones are about $5 or less. Can aalso be checked with meter, should be about 5K ohm (when bad go to 20 -30 K ohms or complete open). You can try swapping those also. 1&4 cap are same and 2&3 are same only because they have to reach a different distance.

If plug is sparking, then suspect fuel. Also when remove plug, the color is of some improtance (but I am not guy to tell you about that.)

Your statement of "only restart on choke" (I presume engine was warm and would not need choke), does sound more like fuel/carb problem. So more of fuel/carb problem (and I am here only cause is posted in electrical section).

Tell us more what you find.

PS: Welcome to GSR. Dont know if I have seen you post before.
If I had, I would have said that my parents were from Johnstown PA area.
Dad from St Micheal up on what was area overlooking the South Fork backwaters, just a side of hill since 1889.
And I have cousins around there yet somewhere. Varner, Gramlin, Morrow.

.

[stoy75]

I have replaced the caps with ngk. The plug from that cylinder has more s
ooting than the others. I thought coil but only one cylinder and independent sort of rules that out. I did pull the plug and there is spark

[BassCliff]

Hi,

Are the float heights set properly? Petcock operating properly? Are you using an inline fuel filter? Is the gas cap venting properly?


Thank you for your indulgence,

BassCliff

[salty_monk]

All good points from Basscliff on the fuel front. Being as number 3 seems a prime culprit float height, float needle etc would be my prime target but the fact the plug is crudded up would suggest fuel is getting through & not being burnt properly.

I have a known good set of coils going cheap in the For Sale section... might be an easy way to discount the coils totally.

I even have an odd one somewhere (you'll have to add wires & plug caps to it as I pulled the old split ones out) that is good that you can have for not much more than a beer....

I would also do the Ignitor tests to see if the box is bad. Fairly sure yours has the electronic advance on it. Not tested one of those (only the mechanical advance kind) but I assume there is a test for it (clymers listed a test for my 1000G).

I had an ignitor box go bad that would work completely fine up to 6k rpm & then just cr*p out.

I had a Dyna Green coil go bad on number 3 cylinder only - basically some loose connection where the plug wire entered the coil was "spark eroding" anything metal there until eventually it completely lost spark on that cylinder.

Out of interest have you checked the valves? If number 3 is way off it could affect the combustion process.

[stoy75]

Yes the heights are fine. The petcock tested fine. Gas cap is venting. And there is no fuel filter.

Hi,

Are the float heights set properly? Petcock operating properly? Are you using an inline fuel filter? Is the gas cap venting properly?


Thank you for your indulgence,

BassCliff

[stoy75]

Would the float affect idle?

[BassCliff]

Hi,

If the float height is too low the carb will starve that cylinder.

Have you replaced the spark plug caps after cutting back 1/4 inch of the spark plug wire to get to un-corroded copper? See: Spark Plug Cap Replacement

Thank you for your indulgence,

BassCliff

[rustybronco]

The plug from that cylinder has more s
ooting than the others.

A cylinder which has no spark cannot develop soot on a spark plug. Soot requires combustion and that would not happen without spark.

[stoy75]

Yes sir. Cut off a quarter inch.

Hi,

If the float height is too low the carb will starve that cylinder.

Have you replaced the spark plug caps after cutting back 1/4 inch of the spark plug wire to get to un-corroded copper? See: Spark Plug Cap Replacement

Thank you for your indulgence,

BassCliff

[stoy75]

Ok went out while at work, shhh lol, and warmed up the bike. Pulled plug wire 2 and no idle change. Pulled plug wire 3 and no idle change. 1 and 4 killed bike. Would a coil going be sporadic like this. That 2 works once in a while and 3 is a dead fish and me cleaning synching and adjusting carbs worked around it so that the bike runs.

[stoy75]

Well kinda runs

[salty_monk]

2 & 3 are on the same coil... It sounds like something is wrong with that coil or the wiring to it (most likely) or possibly (unlikely) the trigger for that coil is not working properly or more likely (than the trigger) something wrong in the ignitor box.

Did you check the voltage at the coil with the bike running?

[stoy75]

Running no. That's a tank off deal?

[BassCliff]

Hi,

Running no. That's a tank off deal?

Yes, that makes it much easier.


Thank you for your indulgence,

BassCliff