Miss

[jackd]

The left rear cylinder, number 1 I think, seems to be dead at idle. When I pull the plug wire, there is no change. I checked and re-gapped all plugs. I made sure each plug was firing. Also, when I turn the mixture screw all the way in, there is no change. All other cylinders cause a change.
There is also a hesitation off idle. I believe I need to clean the carbs thoroughly as this bike sat up for several years. It was cranked on occasion, but apparently not enough. Does it sound like I'm on the right track?

 

[NHVmaxpower]

Yes you are I would remove & clean the carbs replace seals,gaskets,float needles . A quick fix is to do the shotgun .http://vmax.lvlhead.com/tips/shotgun.htm

 

[bazwell]

Sounds like you are on the right track.
If you have access to a carb balancing tool, you could do a shotgun, and then balance the carbs.
If you still have problems after that, them maybe pull the carby's off for a look.

 

[jackd]

Did the shotgun. The idle mixture screws on all four cylinders make a difference when I turn them now. I also found a missing o-ring on the #1 cylinder vacuum diaphragm. I guess the dealer that rebuilt the carbs a couple years ago left it off. The bike hadn't been ridden since the rebuild until I got it. I used two vacuum gauges to sync the carbs. They were pretty close, just off a little side to side. I'll sync again when the fluid comes in for my SyncPro.
I must have a coil breaking down as well. When the bike gets hot, it will have an erratic miss. Every now and then the exhaust note will change for a few seconds and it will be really down on power like a dead cylinder. It runs awesome as it warms up to operating temp, but once it's been there a while and everything heats up it will start the missing. Once I am sure that is the problem, I may do the COP kit.

 

[jfeagins]

Regarding the hot miss: I wonder if it begins missing when the fan kicks on and drags the voltage down below where the CDI box is comfortable? You may want to check your charging voltage at idle both before & after the fan turns on.

 

[jackd]

Regarding the hot miss: I wonder if it begins missing when the fan kicks on and drags the voltage down below where the CDI box is comfortable? You may want to check your charging voltage at idle both before & after the fan turns on.

Now that you mention it, I think it does get worse when the fan kicks on. I will check that. Thanks!

 

[jfeagins]

If it behaves like mine did, and it truly is the voltage causing grief with your CDI, you would be able to see errant spark jump (provided it is dark enough in your garage, or the bike is outside, at night, when you do this testing) from one or more plug wires. The miss is when a spark jumps from a wire, and onto your head or frame somewhere as the CDI box begins misfiring. I spent good money after bad, and nearly pulled my hair out trying, in vain, to figure out how I could be losing spark across perfectly good (new)wires, plug caps(new) & connections, coil wire connections, and new & tested spark plugs.

A regulator/rectifier upgrade solved it for me.

This problem is all too common, and very well documented elsewhere here on the forum, should it turn out to be one, or all, your problem(s).

 

[jackd]

I think I have found my problem. I re-wired the charging system with the information found in the "how to" section. It did not help. I am still getting around 12.3-12.5 volts at idle with the fan on. This is when it starts missing. The stator and the battery seem to be okay, but I am showing a draw on the battery. When I remove the fuse for the R/R, the draw goes away. Sounds to me like a R/R should solve my problems. I hope!
UPDATE: I realized that during all my testing, carb cleaning, and just idling that my battery was down to 12.3 volts. I put my trickle charger on over night, let it set a few hours for the voltage to stabilize, and checked it at 12.7 volts. Now when I crank it up, I am getting 14.4 volts at idle with the lights on! The wiring did help. It will go up to around 15.1 when I rev the engine. Also, with the battery fully charged there is no draw showing on the battery. My only concern now is if the battery is holding a load. When the fan kicks on, it will drop to around 13.9 volts but steadily drop. Over a few minutes, it dropped down to 12.8. I believe it would have kept dropping. When I hit the starter to crank, the voltmeter will flash down to mid 10's on the voltage. Does this sound like a battery that will not hold the load?

 

[jfeagins]

Take the guessing away. Remove your battery. Charge it. Have it load tested.