Right Side Issues, Carbs?

[bcware]

1978 2E with free-flowing exhaust and stock air box

145 mains, ~26mm float height, +1 pilots, ~3 turns out on idle screws, 4th notch from the top on the needles

To my knowledge the carbs are clean, settings are identical on both sides, I just synched them, I have spark, I have compression, the left side is a nice light golden brown, but the right side is not running well.

When I ride the bike I can feel the right side kicking on and off, mostly off, because I get huge surges of power when it fires. The plug on the right side is sopping wet and fairly black after running the bike for a short while. The right sides shoots flames when it does fire Obviously this is because of the extra fuel piling up.

The float seats and needles are original! My full rebuild kit is on the way from sirius. Could I be flooding?

I am looking for some suggestions.

 

[drewpy]

look to the ignition, something may be breaking down (apart from the owner).

its said that 80% of breakdowns in the 70's and 80's was ignition related.

 

[bcware]

Like coils? The right side plug wire also looks a little bent where it connects to the plastic "head" that covers the spark plug.

Oh, and pics! Low res for now... it needs cleaning.

 

[drewpy]

swap the coils over ( not literally, just the wires and grey/orange ones) and see if it changes sides

if you have a strobe lamp, try that and if it don't fire light, there is no HT pulse.

 

[bcware]

I pulled the plug and it sparks when I ground it to the engine. What is an HT pulse? Is it possible for the coil to be bad and still produce a spark? I will do the swap tomorrow afternoon.

 

[DanMach]

Compare the sparks. Just because a plug sparks outside doesn't mean it sparks under compression.

 

[drewpy]

Compare the sparks. Just because a plug sparks outside doesn't mean it sparks under compression.

correct DanMach

HT pulse is the charge of electricity sent from the HT coil. If you are getting a spark then you have that pulse.

 

[bcware]

Ok, thanks guys; that's what I wanted to know. I am heading out to the garage right now.

 

[226dark]

The strobe light test is a great idea. For myself I could hear it was missing but the strobe light showed me that it wasn't sparking and strobing every single time. My initial very first thought turned to the points being dirty or not gapped for the right side. The reason being my pressed-in brand new cam seal was not doing it's job. Right side plug was very obviously sopping wet and fairly black. .. but for a much different reason.

When I ride the bike I can feel the right side kicking on and off, mostly off, because I get huge surges of power when it fires. The plug on the right side is sopping wet and fairly black after running the bike for a short while. The right sides shoots flames when it does fire Obviously this is because of the extra fuel piling up.

Hope it's just a carb issue and it sounds like it. The coil wire swapping test also an idea i've heard - prob from YOC- and haven't tried it.
I was trying for flames from the right muffler but only got smoke

 

[bcware]

I happened to have a 1975 Honda cb360 parts bike sitting in my garage. What's funny is that the coils are the same (same numbers printed on them and everything); the wires are just different colors. I'm in the process of swapping the brackets right now.

The honda even uses the same spark plugs.

 

[bcware]

More problems...

The good news is that I swapped in the new coil and the spark looks stronger and is more consistent.

The bad news is that I left the petcock on over night. The case was flooded with gas and I lost compression. I removed just under 4 liters from the case when I drained the oil!

Some oil in the plug holes brought compression back up, but I still strongly suspect the float needles and seat are not creating a good enough seal and as a result the carbs are just pissing out gas.

The full carb rebuild kit comes in tomorrow. I am going to be mad as hell if the new float needle seats do not fit. In the past I ordered just a set of float needles and seats from partsnmore and they did not fit...

 

[226dark]

More problems...

The good news is that I swapped in the new coil and the spark looks stronger and is more consistent.

The bad news is that I left the petcock on over night. The case was flooded with gas and I lost compression. I removed just under 4 liters from the case when I drained the oil!

Some oil in the plug holes brought compression back up, but I still strongly suspect the float needles and seat are not creating a good enough seal and as a result the carbs are just pissing out gas.

The full carb rebuild kit comes in tomorrow. I am going to be mad as hell if the new float needle seats do not fit. In the past I ordered just a set of float needles and seats from partsnmore and they did not fit...

Hey bc, i wonder if this happens commonly and a bit of debris gets stuck in there. I would think leaving it on that the float needles would stop the flow. Last Sunday when I put everything together I let it sit on Prime and it flooded from the right side and it was just fine previously. The only thing I did with the carbs was remove diaphragm to get the slide action smoothed out. Maybe your old float needles too worn i suppose, but mine are new.
Any case, i get rushed and unmindful (old and forgetful, ha) and that is prob why I just HAD TO HAVE the vacuum petcock working

 

[bcware]

The float needles should do a good job stopping gas flow, but of course they are not designed to act as a stop. I have an aftermarket petcock that does not use vacuum. Still, with the amount of gas that leaked over several hours I have to imagine that the needles are creating a very, very poor seal.

I always have gas on the carb boots and air filters when I take the carbs off as well, but I've always dismissed it as due to my rocking of the carbs to remove them. When the temperature is not near freezing the extra gas probably vaporizes quick enough to allow the bike to start easily, but right now it is still quite cold.

 

[bcware]

OK, so I am sitting here waiting for my rebuild kit to come in the mail, and I decide to take the carbs apart and the photos show what I found. The diaphragms look like they are covered in more gas than I have ever seen.

I have not tried to start the bike since yesterday; it's been almost 20 hours give or take. The temperature has been between freezing and 40 degrees F.

I remeasured the float height and it is closer to 27 mm and yet the carb boot lips and the air filter tube lips have gas on the bottom of them. There is not enough in the air filter tubes to drip out, but it's definitely there.

 

[bcware]

Does anyone know if these diaphragms are leaking? What are the symptoms of bad diaphragms? The bike is not running at all right now; All I can get is a double pop when I kick it over, but it just won't keep going.

 

[bcware]

I'm at a loss here. I need more suggestions. I feel like I have tried everything. The bike will not start. All I can get is a few cycles of combustion, but it will not run.

I have compression, the carb internals are all new, the carbs are clean, new plugs, I have tried swapping coils, as far as I can tell I have a good spark, all timing is perfect. This thing ran perfect all last season. I am ready to start punching kittens.

 

[drewpy]

have you tried some easy start and see if the sparks/timing is ok?
if it kinda runs off that stuff at least it's the carbs, no run and I'd go back to basics and check that the timing is not 180' out etc!

 

[bcware]

Alright, easy start it is! I will give it a try. If it turns out I botched the timing I am going to laugh and punch myself.

 

[bcware]

I just checked the timing; it's correct, but both sides look slightly off. Would firing right before the LF/RF cause major problems? It's only a few millimeters to the left of the RF/LF lines.

I also tracked the valves opening and closing when I checked; they are both closed (the valves) when the respective point opens. So, I am not firing on the exhaust stroke or anything.

I suppose if it is firing a little early I am not getting maximum compression, but is this enough to keep it from starting? I am going to adjust it anyway.

 

[bcware]

Adjusted the timing so it is exact; it made no difference. Starter fluid made no difference. All I get is a thump-thump, and if I am lucky perhaps 4 thumps in a row every 50 kicks.

The coil I swapped in is from another old bike (1975); should I just buy new ones? I am running out of things to replace.

What would happen if a condenser is bad?

At this point I am going to replace the entire ignition system.