Mechanical advance problem?

[doctorgonzo]

Ok, I'm grasping at straws a bit here, so bear with me, and just tell me what you think.

I've been fighting a rich condition ever since I installed a stage 3 kit for my pods. I finally thought I had it a couple weeks ago after I dropped the needles to the 2nd groove from the 3rd groove recommended in the instructions and turned the pilot jets back to 1.5 turns out (instructions were 2.5, I had already turned them back to 2 previously). Drove the bike home, pulled the plugs, chocolate brown, textbook almost. I drove it several hundred miles over the next week, ran great. A couple days ago it started running rough, so I pulled the plugs and they were a little sooty. I think, well, those plugs have been cleaned a zillion times, and being fouled so many times, probably just inclined to foul now, so I installed a new set, gapped properly (upper end of spec, .8mm). I go for a ride and 30 miles later, running terrible. Get to my destination and they are fouled.... I get up this morning, pull the plugs again and clean them. When I fire the bike up it blows black smoke like crazy when you twist the throttle for a couple minutes, then clears (left over fuel from the poor running last night maybe?) Drive 25 miles, and it runs great. I haven't pulled the plugs, but I bet they will not be very sooty.

Here is my question I guess. I'm looking for reasons why one day, I can drive all day and the plugs are fine, the next day they foul in 20 miles...
Is it possible my advance isn't working properly all the time, maybe sticking?

[Nessism]

Advance won't make your plugs foul. Sounds like the bike is still rich.

What kind of bike, year, exhaust, brand of pods, etc?

[doctorgonzo]

Advance won't make your plugs foul. Sounds like the bike is still rich.

What kind of bike, year, exhaust, brand of pods, etc?

1981, GS1000G, K&N Pods stock exhaust.

I got my o-rings from Robert yesterday, and am getting a new diaphragm (slight tear in one) and a couple slide springs from Chef. When everything gets here I'm going to tear them totaly down, and while they are apart, probably drop the size on the main jet. The recommended one in the dyno kit was massive (though I can't recall the number). I'm gonna go to the next lower size.

[rapidray]

Actually, STOCK coils can cause an intermittent problem like that. They are NOTORIOUS for working when cold & losing power as they get some heat in them. If the plugs are "chocolate" the bike is still a LITTLE too rich. NOT much, just a little. I would put money on it being the coils. I have seen it MANY times. Ray.

[doctorgonzo]

Actually, STOCK coils can cause an intermittent problem like that. They are NOTORIOUS for working when cold & losing power as they get some heat in them. If the plugs are "chocolate" the bike is still a LITTLE too rich. NOT much, just a little. I would put money on it being the coils. I have seen it MANY times. Ray.

Not stock, aftermarket 3 ohm Dyna, BUT that doesn't mean they don't have a problem. I keep leaning ignition as well. I'm going to start at the plug caps (which are also pretty new) and work back from there just to make sure.

[Nessism]

Stage 3 kit is designed for pods and a header. I'm not surprised your bike is running rich.

[doctorgonzo]

Stage 3 kit is designed for pods and a header. I'm not surprised your bike is running rich.

According to Dyna, Stage 1 is header only, stage 3 is pods or pods and header. Adding the header changees the instructions to an even larger main jet.

[flyingace]

Ok, I'm grasping at straws a bit here, so bear with me, and just tell me what you think.

I've been fighting a rich condition ever since I installed a stage 3 kit for my pods. I finally thought I had it a couple weeks ago after I dropped the needles to the 2nd groove from the 3rd groove recommended in the instructions and turned the pilot jets back to 1.5 turns out (instructions were 2.5, I had already turned them back to 2 previously). Drove the bike home, pulled the plugs, chocolate brown, textbook almost. I drove it several hundred miles over the next week, ran great. A couple days ago it started running rough, so I pulled the plugs and they were a little sooty. I think, well, those plugs have been cleaned a zillion times, and being fouled so many times, probably just inclined to foul now, so I installed a new set, gapped properly (upper end of spec, .8mm). I go for a ride and 30 miles later, running terrible. Get to my destination and they are fouled.... I get up this morning, pull the plugs again and clean them. When I fire the bike up it blows black smoke like crazy when you twist the throttle for a couple minutes, then clears (left over fuel from the poor running last night maybe?) Drive 25 miles, and it runs great. I haven't pulled the plugs, but I bet they will not be very sooty.

Here is my question I guess. I'm looking for reasons why one day, I can drive all day and the plugs are fine, the next day they foul in 20 miles...
Is it possible my advance isn't working properly all the time, maybe sticking?

I agree with the still running rich theory. Why don't you make whatever carb adjustments you need until you get more of a light tan plug read? I for one don't go along with the notion that dark brown plug = perfect. I think you are marginally too rich, and over the course of a ride, the condition overwhelms the plugs until they get sooty and fouled.

[doctorgonzo]

I guess dropping the main jets a size when I tear the carbs down is next. Already dropped the needle and taken to pilot to 1.5 turns. Not much else I can do without changing jets.

[salty_monk]

It could also be a combination of both... slightly rich & a weak spark. If the weak spark is intermittent it would explain your prob to a certain degree.

Dan

[doctorgonzo]

It could also be a combination of both... slightly rich & a weak spark. If the weak spark is intermittent it would explain your prob to a certain degree.

Dan

This is what I think as well. Coils are new Dyna, wires are new, caps are new, coil relay mod done... at a bit of a loss. Even with coil relay mod, only have about 10 volts at the coils with bike not running (was 8 before the mod). Never checked it with bike running. That might worth a look.

[chef1366]

Dang! You have a Dynojet kit! I repacked the slide with JB weld and drilled it back to stock. What a waste of time that was. You did drill out the slides right?

If you drilled out the slides, pressed in the smaller main air jet and installed the Dynojet jet needle I would got with this setup.

Needle at third up from the bottom. (Dynojet's settings tend to be lean)

The Dynojet 165 main jet is like a Mikuni 155. Don't install the 118 Dynojet main jet. It will be too lean. This is like a 110 Mikuni which is smaller than your stock main jet.
Go to your suzuki dealer or someone that sells Mikuni large round main jets and get some 140s. Do some plug chop at wide open throttle on straight away and pull the plugs. A light cocoa color is ideal. If it's white go to a 145. If it bucks and is lean go up to a 150. If it is still dark go down in sizes the same way. You'll get it dialed.
I hope your ignition is good.

[doctorgonzo]

Dang! You have a Dynojet kit! I repacked the slide with JB weld and drilled it back to stock. What a waste of time that was. You did drill out the slides right?

If you drilled out the slides, pressed in the smaller main air jet and installed the Dynojet jet needle I would got with this setup.

Needle at third up from the bottom. (Dynojet's settings tend to be lean)

The Dynojet 165 main jet is like a Mikuni 155. Don't install the 118 Dynojet main jet. It will be too lean. This is like a 110 Mikuni which is smaller than your stock main jet.
Go to your suzuki dealer or someone that sells Mikuni large round main jets and get some 140s. Do some plug chop at wide open throttle on straight away and pull the plugs. A light cocoa color is ideal. If it's white go to a 145. If it bucks and is lean go up to a 150. If it is still dark go down in sizes the same way. You'll get it dialed.
I hope your ignition is good.

Ha! I guess I should have told you. Yes, the slides are drilled. I'll just drill it out again, no sweat.

Now that you say it, I'm pretty sure I have the 165's in there. A plug chop is what I need to do. I've just been putting it off. I'm guessing my jets are too big. I have taken the needle from the third notch to the second notch and turned the pilots in to 1.5 turns and I still have black plugs, but with no plug chop I don't know which circuit is doing it. I'd been putting it off because I want a 4 into 1, but other repairs have made me keep putting off buying it, so I guess I need to bite the bullet and get it set up right for how it sits now.

As far as the ignition, some things make me want to think it's involved, but as I said in an earlier post I have
New Dyna 3 Ohm coils
New copper core wires
New NGK 5k Ohm caps
The coil relay mod
Many times replaced new plugs
A new igniter
The only part of the whole ignition system not new is the signal generator.

I asked about the advance because at one point I pulled the cover and it was a horror show of rust (the advance). I cleaned it up with a wire brush and some WD-40 but wondered if it might be sticking, thus not advancing/retarding the timing correctly and causing incomplete fuel burn.

[chef1366]

If the main is too big it will also make the needle rich. Dial in the main first and then the needle.
With the stock pipe the 165 is too big.