Well Four Cylinders Are Better Than Three

So I been having some power issues, and lately its been really bad. bogging down, unresponsive to the throttle and sputtering out of the carb throat. I checked my spark plugs and found two were covered in soot and two were lean. The fuel/air mixture screws were not set right and for good reason...they were unresponsive so I left em where they were at when I got sick of messing with em.

Today, I couldn't get the bike to start. Took the spark plugs out, gapped them, put em back in and still nothing. I took em out, tested them and to my dismay, one was dead, one was sparking the side of the ceramic instead of to the electrode. So off to O'riely Auto Parts I went.
I put the new plugs in and it still wouldn't start. I sprayed some starting fluid, started it and it scared the crap out of me, it sounded like I never heard before (in a good way) and the RPM's shot to the to top and limiting out, setting off a car alarm in my garage. I killed the bike and investigated. Found nothing obvious. Started it again and it did the same thing. Except this time I turned down the choke and tried doing my regular fidgeting to get it right but there was no in between. Red line or almost die. I remembered that I had turned my idle fairly high to make it idle regularly so I turned it down. Started again with choke all the way on. It didn't red line. I was surprised

I let it run. Stoked to hear it running different, so beautifully. I revved it up in my parking garage and a car alarm went off again. haha

The header wrap from the dead cylinder has been collecting oil and it started billowing smoke, filling my garage haha. Being legitamately scared it was going to catch on fire, I ran the bike out side to the street. My header wrap looked like a pimple ready to pop sizzling away.

All in all this bike is running beautifully and It really sounds like a completely different bike. Its crazy. I oiled my dry ignition advance as well. I have yet to ride it like this because I have to burn all that impregnated oil off my wrap. It billows smoke like no other haha.

Thats todays story with it.

To hear and feel what I thought was normal, unplug your number 4 cylinder. I thought that was what it was supposed to be like for the past three weeks. I was before surprised by the power, so now I don't know what to expect.

I'd check the resistance of the 4 sparkplug caps. They should test at 5000 ohms.The caps go bad from heat and vibration & new ones are available at most Japanese motorcycle shops. Still got the original ignition coils & sparkplug wires? Read this:

Ignition Coils And Sparkplug Wire Choices

What came with the bike, were ignition coils that even when new were marginal, add years of cooking under the tank in the stop and go traffic, and the coils will probably fail when hot.

Replacement coils can be bought at www.z1enterprises.com I believe “Emgo” is the brand. They also carry the popular Dyna 2.2 and 3 ohm coils, along with replacement sparkplug wires.

Now, you have a choice on sparkplug wires:

1.Copper plug wires with no supression caps (the best choice, but will produce audio noise on Radio’s and TV’s). Not only do the copper core wires deliver better spark, they will also deliver a much longer lifespan - carbon core wires are prone to erratic spark delivery and early breakdown, & short lifespan.

2.Copper plug wires with supression caps (a built in 5000 ohm resistor, that can sometimes fail, like what came with the bike). These should be checked with a multimeter now and then, as heat can cause them to become intermittent.

3.Copper plug wires with no supression caps, but using resistor plugs(the “R” in the plug number).

4.Supression plug wires with no supression caps.

NEVER use resistor plugs combined with supression caps along with supression plug wires, as now there will be possibly three (3) sources of resistance in the secondary windings of the ignition coils, greatly reducing the spark energy.

Another choice is the Accel 3 ohm coils, with a similar, primary(small wire)electrical connection, using ring terminals as the Dyna ignition coils do. Whatever brand of coil you go with, make sure the primary wires will clear the mounting hardware, as the spacers come close, possibly blowing a fuse. Some riders have replaced the metal spacers with non conductive Nylon spacers, reducing the chance of an electrical problem.

7mm sparkplug wires will fit the stock ignition coils(if they have replaceable wires, indicated by screw off caps on the coils with ridges). The sparkplug wires fit into a port with a brass ”Stinger” that goes into the sparkplug wire or lead(the Brit’s. Canadians, and other countries call the sparkplug wires (“High Tension Leads”).

A video on installing an Accel 3 ohm ignition coil (Adult language used):

Tried another brand of sparkplug? The NGK's made in the U.S. seem to be having a quality problem; I've had several new ones fail right out of the box. Look at Bosch,Accel,Denso, or Champion sparkplugs as alternates to NGK's.

Well I cant be completely sure, spark plug wires are NKG, I cant speak for the coils. It has been upgraded with a DYNA S electronic ignition at some point. So I assume the coils were upgraded too though they do look past their date.

I believe what the problem was...and how I lead to my conclusion is

Give me a minute for a deep breath haha

I picked this bike up when I was a light mechanic at a motorcycle shop. The customer kept bringing it in because of suspected carb issues. They would be cleaned and three weeks later he would come back in with the same problem. His carbs were cleaned time and time again by the main mechanic and the gas tank eventually relined because of suspected rust. The ignition or float adjustment was never held culprit. He would adjust the spark plug gap and give the tip a sanding and pop them back in. Thats it.

Now when I found the 2 plugs covered in soot and two of them failing I remembered when I adjusted the float hight a couple of weeks ago the two carbs were so out of adjustment that the clear tube test showed the levels were about, if not over, a half an inch above the bowl. This caused gasoline to overflow the throats into the cylinder. My oil and high fuel turnover told me so.

Also lending to my argument, the wrong plugs were in the bike, B7ES, so I know they were never changed by the shop I worked at cause we had a stockpile of B8ES and we would use the NKG website when we put plugs in every bike. (Confirmed, The website says B8ES)

Which finally leads to the ownership of me...

I adjusted the crap out of those carbs, I will argue with full confidence in the work I did but I still never changed the plugs. Eventually (last week) my plug failed giving me that 'made famous' loss of power the previous owner was dealing with. I investigate and find two plugs are bad.

What I gather from all this is...

The carbs were so far out of adjustment before that the two cylinders on the right were carbon depositing on the plugs and over time to block the spark. He would bring it In, the mechanic would do a light clean on them then pop them back in. Not a bit suspecting of them, only to build the same again over time.

I conclude this with...

The bike ran today like never before, all the times he brought this bike in, it NEVER sounded like it did today. It especially wasn't near as responsive on the throttle. Even after the cleaned plugs. So I believe the entire time the plugs were fouling up from the carbs. Even after my adjusted carbs being put in place they were too far gone from being abused and crutched along for so long. Making for the immanent death and the head scratching in figuring this bike out.

Mostly though, the contrast of the revised choke operation, sound and throttle response is what makes me feel right about this conclusion

I didnt mean to talk around your words of advice. But these are a picture of the NKG wires, maybe you know something about them?...and this is my header that was billowing smoke after I changed the spark plug.