Idles and revs great in neutral, runs like crap around the block

[taunusrainer]

I've been saying that since post #4 but everyone keeps pushing electrical.

Ah, right, missed it.

[LowNSlow]

So it idles and revs well in neutral, when You start off it gets worse and when you go back to neutral and let it run it gets better?

Definitely not a spark problem. Too little fuel coming from the tank.
- tank cap not venting or
- fuel lines clogged or
- petcock blocked or
- dirt in the tank or
- dirt in the filter or
all of these....

It did, but no longer starts easy or runs worth a hoot. Definitely having a spark problem at the moment as well.

While difficult to follow, I may be having some fuel delivery, but a seemingly worsening spark problem

[LowNSlow]

So it idles and revs well in neutral, when You start off it gets worse and when you go back to neutral and let it run it gets better?

Definitely not a spark problem. Too little fuel coming from the tank.
- tank cap not venting or
- fuel lines clogged or
- petcock blocked or
- dirt in the tank or
- dirt in the filter or
all of these....

I've been saying that since post #4 but everyone keeps pushing electrical. I'm waiting for more diagnosis on fuel delivery.

That is where the diagnosis should be. It's possible that enough dirt got into the carbs that they need to be pulled and gone over.

.

See posts 30,31, 32 for some info on fuel delivery.

Also note that the first thing I did was convert to a single VW carb with no change in result, leading me to believe not carb specific (maybe fuel delivery or spark related). It’s only gotten worse in the past week or so.

I have also manually filled the carb with fuel and still wasn’t firing on all 4, at one point evidenced by raw fuel coming out exhaust.

[taunusrainer]

I suppose I should pull the tank and give it a good cleaning.

That's where I would start. I would drain the fuel, there is a hidden drain plug on the bottom of the tank. Flush it to see if dirt comes out. Then I would unbolt the petcock, two holes to the tank will show up. Blow through with compressed air. Maybe the tubes inside the tank are clogged. Flush tank again if You feel there was something blown into it. Blow through the petcock and reattach it. Then put fresh fuel in the tank and check if there is a good flow of gas coming out from the petcock both in normal and reserve. New hose and filter to the tank. If the problem still exists, I would address the single carb. Open fuel bowl to see if there's dirt. Blow through all jets and passages. Install new spark plugs. If the problem still exists, then I was wrong and You actually have an ignition problem. But the symptoms clearly indicate fuel starvation imho.

Edit: Just seen You have already done the tank procedure. Then I am out, I also run a Dyna ignition for decades (Dyna III) and never had a spark issue, except when I mixed up the spark plugs one day...
Curious what You will finally find out as the "corpus delicti"

[robin1731]

snip......
I have also manually filled the carb with fuel and still wasn’t firing on all 4, at one point evidenced by raw fuel coming out exhaust.

That sounds like way too much fuel. Even week spark will fire the correct air/fuel mixture enough to not pour fuel out the exhaust.

I've seen fouled plugs on bikes that did not have raw fuel out the pipe. What do the plugs look like? What does the oil smell like? Is the oil level high?

.

[LowNSlow]

snip......
I have also manually filled the carb with fuel and still wasn’t firing on all 4, at one point evidenced by raw fuel coming out exhaust.

That sounds like way too much fuel. Even week spark will fire the correct air/fuel mixture enough to not pour fuel out the exhaust.

I've seen fouled plugs on bikes that did not have raw fuel out the pipe. What do the plugs look like? What does the oil smell like? Is the oil level high?

.

They were “black”, and at one point, very wet
I spun over the engine and blew out the excess fuel, left it to dry and went after new plugs.
Spun the engine over again, installed the plugs and no different. It struggled to start and then only ran on what seems to be 2 cylinders.

I’ll go check the oil and odor.

[LowNSlow]

Oil level is good, below the upper mark in the sight glass. Hard to tell about odor without draining some and getting it away from my bike. Everything smel like gas at the moment. My tank drain bolt has a slow drip after draining the tank on Friday. Will a new drain washer help that, like on auto oil pans?

[pidjones]

The lack of power did happen to me once when the charging stopped on an RD250 - barely made it home. But, you say you have tried that (I'd still try a digital voltmeter while riding - duct taped to the shelter).

[Sidecar Bob]

A new washer wouldn't hurt.

The best way to smell the oil without draining some is to sniff the dipstick. These don't have dipsticks (cheap & easy dipstick instructions: viewtopic.php?t=2804 ) but if you dip a piece of stiff wire into the filler hole you should be able to dip out enough to smell.

[LowNSlow]

A new washer wouldn't hurt.

The best way to smell the oil without draining some is to sniff the dipstick. These don't have dipsticks (cheap & easy dipstick instructions: viewtopic.php?t=2804 ) but if you dip a piece of stiff wire into the filler hole you should be able to dip out enough to smell.

I like that makeshift dipstick. I was peering down the hole trying to see and sniff and whatnot, so I can see what you mean about reaching the oil.

[LowNSlow]

I pulled my tank on my lunch break today (working from home). If I can’t wait until after 5, I’ll use one of my “smoke breaks” to clean it out. I’m just waiting on Thursday for coils to arrive anyway
I’m hoping that’s the answer to my weak or nonexistent spark. It’s sure cheaper than a new dyna ignition.

[LowNSlow]

That was an embarrassing amount of gunk in my tank. I drained all I could and then poured the last pint into a paint cup. I’ll strain it later and see how it really looks. Right now it’s still brown and I can’t see the bottom of the cup. Filter was nastied up again as well. No surprise. It’s the cleanable element type

[Sidecar Bob]

Replacing the coils is only cheaper if if that's what is actually causing the problem. Did you ever switch the coils to see if the problem moved with the coil?

[pidjones]

I would use a few paper element disposables until it clears up. I think they filter down to finer particles. Have you drained your float bowls to see what is getting into them?

[LowNSlow]

I would use a few paper element disposables until it clears up. I think they filter down to finer particles. Have you drained your float bowls to see what is getting into them?

i have plenty of those. Good idea.
I’m currently running a single Solex VW carb. At least that makes it one bowl to check