Speaking of spark troubles

[mjn12]

I was checking my spark the other day because depsite all my efforts the bike runs heavy on the left cylinder at low RPMs, the right tends to miss a lot until I get above 4000rpm. Carb adjustments are identical and should be balanced. 

While I checking the right spark I grabbed the wire and noticed little shocks - like static electricity.  In the high voltage work I've done we do all kinda of tests that check to see if a conductor is leaking to ground more than it should be (everything does a little). When its happening its BAD and can eventually cause some explosions. However, I'm less familiar with what should be expected from the GS.  Should this be expected or is the insulation breaking down and giving the spark a path to ground besides through the spark gap resulting in poor spark in the cylinder? Any other tests I can perform to check this.

[Chuck]

I'm curious, too.  My plug caps always shock me, it's friggin annoying, but the bike runs fine.

[Egaeus]

It's completely normal.  The spark is capable of tens of thousands of volts, so it can make quite a long spark, and often, the shortest path to ground is through your hand.  Use a towel, glove or other additional insulation to help prevent it from happening. 

[mjn12]

grr, I was hoping this was my answer. Never that easy.

[The Buddha]

Its either bad connections at the 4 way plug (kerry has posted that with pics) under the left tail section. Or a bad crank trigger - AKA the other end of that 4 way plug. Under the right round cover on the motor.
Cool.
Srinath.

[mjn12]

Srinath,

Thanks, I did a little searching and it sounds like what kerry described - once the bike warms up I lose a cyliner.  However mine occurs only at very low RPM, once I get it above 4k it stops "stuttering".  But at higher RPMs the system is producing more juice - maybe masking some deficiency in the electrical system.

I've had the right side cover off to manually turn the crank as described in the clymer manual and nothing *looked* messed up so maybe its shorting in there somewhere.  I'll warm it up and step through the electricals with the ohm meter and see what happens. 

[The Buddha]

The right side will look great even it it will not run on 1 cyl.
On my virago 535 and I am sure itseasier on a GS, I made a set of wires and connectors that will let you run the right cyl off the left ones trigger, you'd swap it back at the plug coils do you dont start sparking into the intake cycle ... but ... that is extreme ... you clean it, and my next stop is carbs.
BTW ... WTF ... you ahve a tight valve ... just a shade tight ... you will start fine, but 5-60 seconds after you'd lose a cyl, then once you have temperature as in fully fully hot it will be fine. Higher RPM's are usually better.
Your symptoms are a shade different. But make sure valves are OK. Warm up trouble sometimes is valves. Usually valves increase clearance when they get fully hot. but as its warming up ... its anyones guess what it does. A marginally tight valve can well be too tight in the warm up stage and go back to being just perfect when fully hot.
Cool.
Srinath.

[mjn12]

I already did the valves a couple months ago, a 2 were tight but thats been taken care of.  Maybe I'll double check them over the winter just for sh*ts and giggles.  Since I'm pretty confident my carbs should no longer be giving me troubles I want to check the electrical. 

I'll have a fully stocked, climate controlled garage in ohio complete with lift and everything in a couple weeks. Till then I'll just ride it and make do.  The right amount of love keeps it running and it doesn't seem to be getting worse.  As long as I keep my revs up I'm running on both cylinders.

[Egaeus]

Wait, "should be balanced?"  What do you mean by should?

[mjn12]

well I made balancer and assuming it works, they're balanced. 

My field service experience has taught me to never assume anything is sure.

[Egaeus]

Did you balance them at 1750 RPM?

Did you replace all of the o-rings?

Did you check for other vacuum leaks?

What do the spark plugs look like?

[mjn12]

yah, I balanced at 1750 or pretty close
o rings were good and tested fro vac leaks (w/ a can of starter fluid)

Left plug - dark brown/tan color (pretty close to what it should be right?)

Right Plug - black

I'm just going to wait and go over it with my uncle when I'm home in ohio. Hes got a nice garage and tons of experience. I've done all I can in my apartment parking lot.

[Egaeus]

Have you tried switching the coils?

[mjn12]

Thats next.

I've given up till I get a garage, its getting too cold and too dark to work in the parking lot.