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I have found the best way to clear out a bike that is loaded up is to remove the plugs, ground them on the head, turn the gas off, choke off, and ignition off. Put the bike at the top of an incline, put it in first gear, and push it with the throttle wide open. 100 or 150 ft should do it. Sometimes you can see the gas spraying out in a mist. Put the plugs back in, and it'll usually fire up. The reason I was getting 2.8 ohms on the left coil, was because the points were closed. If I opened up the points, (with the ignition on) it would jump back up to 4.4 ohms. I bought some B7ES spark plugs, they are the only ones that the bike will not foul. It was still running mostly on the right cylinder. I then took the generator off, to check the wires. Everything seemed to be fine until I spied a condenser wire (for the left cylinder) that appeared to possibly be rubbing against the generator housing. The insulation looked to be somewhat flattened (on one side) almost as if it was abraded or possibly partially melted. There was no indication of arcing on the generator housing. It didn't look too bad, but enough to be suspicious. So I insulated the wire, and put the bike back together. On the bench when I fired it up it sounded fine, so I took it on the road to put a load on it. I rode it for about 10 minutes, the left side didn't cut out at all. Other than the carbs being somewhat out of sync, it ran gangbusters! So hopefully it looks like with some minor adjustments and I'll be good. I am kind of concerned about using B7's, as it is a hotter plug. I also turned the oil pump as lean as I could get it, I'll do a plug check later when I get some time on it. Is anyone out there using B7's?? In addition, I would like to thank all of you for your time and advice. With a little luck I'll be race ready for this  spring.

The condensers are new. With no wires connected, the left coil reads 4.4 ohms. Fully connected, for some reason it jumps down to 2.8 ohms. That reading is with the key off. The right coil, reads 4.4 ohms connected or not

I replaced the left coil. It had 4.4 ohms before I installed it. After installation, I rechecked it. The coil showed showed only 2.8 ohms. I checked the other side, 4.4 Ohms on the right side. Then I unhooked the orange wire on the left side coil, it showed 4.4 ohms. I then turned the ignition on, and checked the left side coil again. This time it showed -1. The coil was getting voltage from the battery on the left side. The right side was fine, it showed 4.4 ohms. I was checking the connections by the battery, and happened to put my hand on the left coil. It was noticeably warm! The left coil is getting voltage from the battery, and going through the system and heating up the coil. I'm surprised it occasionally fired at all on the left side. Has anyone ever experienced anything like this? The problem must lie with the rectifier, the voltage regulator, or somehow the generator.

I have had the motorcycle running with the headlight on, and with it off. Have not noticed any changes. It has been missing mostly on the left side, I left the gas on, and let it sit for a few minutes. There was gas coming out the Overflow tube of the left carburetor. I have the valve needle seats on order from Mike's XS. Hopefully I'll be able to install them in a few days.

Perhaps I should be more exacting when describing what the bike is doing when it is running. Instead of calling it a misfire, I'll opt out for a description. When RPMs are applied, one side would cut out. It would not fire at all, or just sometimes on one side. (Seems to mostly idle with both cylinders working) There is no backfire, or popping. It simply would stumble a little bit when applying RPMs, then quit firing. Occasionally when RPMs were applied you would hear the cylinder sometimes fire back up, then stop. It would also switch sides, and exhibit the same symptoms on the other cylinder, but only after restarting.

Got the clutch working properly. However the bike seems to not be firing mainly on the left cylinder. Up on the bench, I hooked a timing light to the spark plug on the left side to see if the ignition was firing. The light ran like it should have with the cylinder firing properly. When it was not firing, (while running) the light still seem to be firing properly. To me, this indicated that the problem was not with the ignition but carburation. Both spark plugs were wet after the bike ran. The right side seem to be as wet as a left, but there was a slight coat of soot on it. Jetting is stock. Floats have been set properly. Carburetors are very clean inside, all passages are clear. I made the mistake of buying a cheap set of valve needle seat assemblies, the brass was too long so I didn't use them. I have been running the stock assemblies, which looked to be fine, could they be sticking?

Fired the bike up on the bench. This is the first time that it has ran with the champion 805 non-resistor plugs. It idled fine, and revved cleanly, sounds very crisp. Going to take it out tomorrow for a test ride. Will put a load on the motor and see if it reves cleanly.

The carbs are in really decent shape internally. I have checked every passage with contact cleaner and compressed air. I installed new float valves, I checked the floats, I even weighed them! I checked the pilot and Main Jets to ensure that the numbers were standard, the air screws are out one and a half turns. I don't know what a snail sink is, trust me, they're opening up identically. These are stock carbs, there is a crossover tube. And it does not run better with the choke on. But when running, this seems to happen around mid-range to the upper throttle the symptoms are better described in some of my past posts. The tank is pristine, and I am running filters. It's not entirely a carb issue because it was missing on the right cylinder, and then magically switched to missing on the left cylinder. To me, that is indicative of being an electrical issue. I've almost got it back together, and I'm going to take a test ride tomorrow after fixing the clutch. If it is still missing, then I'm going to replace the coils. The ones that are on it came out of a pile of coils and I absconded with two of them. I verified that the serial numbers on the coils were the proper numbers.

Correction: Champion 805 spark plugs are equivalent to a NGK B-8es. This is a non-resistor spark plug, which produces a little bit hotter spark than a NGK Br-8es. (They are available at the local auto parts store) NGK no longer produces the B8-es. I am hopeful that changing to a hotter spark plug than the autolight 4063 will cure the misfire.

Thanks for the reply. I had no idea that FZ600 fiber plates would fit. They are probably far superior to the aftermarket reproduction ones I had bought. I am anxious to see how the RD will run. What year FZ? Will the metal plates fit as well? (Most likely I will end up replacing the clutch pack)

A light Checker unit on an 73 rd350 is located in front of the coils, behind the steering head.  There are three wires coming from the dash that plug into it.

It has been taking forever to get my parts in. A light Checker unit is simply a 12 volt light bulb connected to a couple of wires, ending in alligator clips. (It's easy to make one,as I did) The bike seemed to idle fine, but when RPMs were applied, one of the sides would misfire. At first it was just the right side, then later it switched to the left. This was pretty damn confusing. I am still using the same coils, they are stock, but they are not original. In the interim, I discovered that the autolight spark plugs I was using were equivalent to a br-9es. I found the champion equivalent to a b-9es, which is an 805. When I fired the bike up, it seemed to be improved running on the bench. Received the fiber plates for the clutch last night. When I took the clutch apart, I discovered there are no rubber dampeners in between the metal and fiber plates. (7) I am now hesitant to reassemble without these parts. The local Yamaha shop wants $21 a piece, which I think is out of hand. Question: are these rubber Parts in between the plates really necessary? Could the source of the misfire malady been caused by using plugs that were too cold of a heat range? My RD has the DG heads  (which is why I'm using an ES instead of an HS plug) and expansion chambers.

Update: There is 13.4 volts going to the battery while bike is running. Replacing Springs on clutch was inadequate, must replace clutch pack. In spite of misfiring, and the clutch slipping,  it feels like the bike is capable of making great power.

Update: Installed copper core plug wires and non-resistor caps. Fired bike up, it is now misfiring on the left side instead of the right.(right side is running fine) Rechecked timing, and carb synchronization. I have not replaced the coils. Has anyone out there experienced this type of malady? Any input or information would be appreciated I haven't seen this before. I'm about ready to get some bongos, put on a grass skirt, headdress, and see if I can excise the Gremlins from this bike.

Thank you for your advise. Brass is original, the floats are the closed cell plastic type. Both floats weigh 2 grams. The emulsion tubes were checked, no corrosion. Since the plug wires and caps are suspect,I will replace them, (and the coils) before startup. (Will check the charging circuit then) The battery of course, is new, and well charged before the test ride. I felt that the plugs were dirtier than need be for such a short ride, they appeared a little "damp" (25 pilot/150 main) I didn't really get to row thru the gearbox, as the clutch was slipping. Parts are on order.