82 GS850G no spark cylinders 2/3

[Guest]

Tried swapping coils. No change. 12 volts at coil. Shot wires in wiring harness and they show continuity. Thinking cdi box problem but its an expensive guess if im wrong. Cheapest ones i see on ebay are in the 180 dollar range. What am i missing?

[Nessism]

The 1100G ignitor is the same. There are several on ebay for about $100. Another option is to install a Dyna S. You will have to purchase an advance governor though so that will further add to the cost.

[Downs]

Ive got a Dyna ignition on my 78 1000. Like it quite a bit. Is there anything else i could be overlooking that im not thinking of? The pickup under the right side crank cover?

[Big T]

Everything that makes the spark can be tested.
Break out the multimeter and get to it

[Downs]

Coils checked good, wiring continuity checked good. How do you test a CDI box with a multimeter?

[Nessism]

FSM 17-29 has some checks.

Unfortunately, you need a special tool to check spark. May as well just check on the bike...which you obviously have done.

[Downs]

I found a test procedure for the signal generator in the GS1100 FSM. As well as the cdi box that involves unhooking the signal generator lead, then grounding the spark plug and jumping two wires on the cdi box side of the signal generator lead that will cause the plug to fire if the cdi box is working right.

Ill test the signal generator before heading off for work in the morning and if that checks good ill check the CDI box if i have time.

[Nessism]

This may seem like a nitpick but your bike doesn't have a CDI. It's an ignitor and printed as such all over the FSM.

[Downs]

Yes ignitior. Ive just called it a CDI box forver. Hard to change my venacular.

[Downs]

Did testing this morning on ignitor and signal generator. Sognal generator tested right in the middle of spec. Im not sure if im testing the ignitor correctly as im getting nothing from the 1/4 side or 2/3 side.

[Downs]

[Downs]

I pulled the ignitor out and took some pictutes. Im not seeing anything out of the ordinary except maybe some corrosion and old epoxy.

Maybe a burnt resistor but theres only one this size and ohm rating on the board and the 1/4side still works.

[Downs]

I found an igniter on EBAY. I now have spark on cylinders 2 and 3 but still don't feel like I'm getting any combustion there. Exhaust port temps as read with an IR temp gun is showing 280 degree temps on cylinders 2 and 3 and 400ish on 1 and 4.

I did the ignition coil bypass and put them on a relay powered straight from the battery. It made the spark on all cylinders much hotter. Still no joy on getting anything from the middle two cylinders.

At this point I'm thinking I may have rebuilt the carbs improperly but I have a hard time believing it would only effect the middle two cylinders the same way.

Not sure where to go from here on this one. Taking off from a stop sign or stop light is a struggle for the bike. Once the revs get up to about 5k or so it feels like the bike gets a kick in the pant.s

[Downs]

Pulled the plugs and found the #2 plug to be as new as the day I put it in, not even wet with fuel. #3 plug had some soot, 1 and 4 look like normal for a bike that's been running.

Decided to yank the carbs and see what was up. #2 float bowl was dry no fuel. Found the float needle stuck in the bore. Pulled it free and used a .17 caliber bore brush to clean it out which worked perfect. #3 carb I found the idle/midrange or whatever it is (in front of the main jet under the rubber plug) clogged. So I spent most of the ride today running on 3 cylinders at higher speed and 2 cylinders at low speed. Keep in mind I did a full rebuild on these carbs, all the way down, carb dipped, new orings all that jazz. This is what happens when you loose motivation part way though a project and let ethanol gas ruin your work.

I went ahead and ordered up new carb boots and airbox boots as well today along with all new set of boot clamps. Hopefully I have all this sorted and can move on to the electrics at the end of this month.

[Burque73]

Nice! I'm glad you found the issue.

Just curious, how long did the carbs sit with the ethanol gas in them after you rebuilt them? Just wondering about the time frame it takes for the ethanol to cause problems.

I've been using an enzyme fuel additive called Startron for years. It's supposed to stabilize fuel and help prevent problems from ethanol. I understand that if the engine has fresh gas running through it all the time, it's not so much of an issue. Ssometimes my bike will sit for two or three weeks without riding so I figured it couldn't hurt to use this stuff.