Your gonna hate me for this

[whiterabbitt]

ok so I got the colortune and got my pilot settings close, then I go and do plug chops to confirm and fine tune. ride check adjust ride check adjust ride check adjust etc...
I can dial in all but the #1 carb, no matter the setting the plug is black on low speed chops. I seriously mean no matter the setting, at one point I went to give it a little tweak and the fuel screw was almost seated, it seated as soon as I touched it, and the air screw was at 2 1/2 turns out! double check with the colortune and it says im lean as hell on that cylinder, of course.
sooo.... what the hell??? am I missing something? ive been into the carbs a ton of times trying to figure this out and now im just frustrated.
any input would be appreciated, as im ready to take that carb and smash it, right after I get a replacement, if I cant get this figured out.

btw all plugs are the same color of tan when I do needle and main chops, its just the pilot circut on the #1 I am having an issue with.

[tkent02]

The Colortune says lean and the plug says rich?

Are the carbs synched?

Is the spark plug wire in good shape?

[whiterabbitt]

yes the carbs are in sync. as for the plug wire it is original, looks ok. I was having an intermittent misfire but that went away when I cleaned the connections to the coils. while I was at it I took the springs and stuff out of the plug boots and cleaned those too.

curious isnt it?

[posplayr]

something else to look for might be a broken insulator on a spark plug; got me a while back

[TheCafeKid]

something else to look for might be a broken insulator on a spark plug; got me a while back

Yup. And the plug boots themselves. They more or less dry rot inside and don't hold the connector well anymore.
I once had one of my GSes suddenly start running like total garbage when I got caught in a downpour. I limped her the 5 miles home running on three, sometimes two cylinders. Had to gas the hell out of her to keep her running at lights, etc. The five mile trip took 20 minutes. Once I got home I went to work hunting for a bad connection in the ignition. Then decided to pull plugs to watch spark and two of the boots basically disintegrated in my hands. Guts fell out of em, plastic/ceramic whatever they're made of crumbled...
Bad on me for not changing them out sooner. Lesson learned.

Besides that, are you certain your floats are set correctly, the fuel transfer tube is clear, etc??

[whiterabbitt]

not a bad plug as I have swapped them around to see if it followed the plug, and swapped the whole set of plugs for the next round of chops. (I keep some 4 sets on hand and 2 sets of b7es plugs too!)
float height is exactly 26mm double triple and quadruple checked into submission
fuel transfer tube? between the carbs? or the little brass guy in the bowl?
is it possible that my enrichener is not shutting all the way down? out of everything in the carb thats the only thing I havnt checked over and over. something I just thought of btw.

and can someone direct me to a good how-to for checking coils and plug leads, the clymer offers no explanation, something with resistence values and such

[cableguy]

Maybe new plug caps (boot) are in order, they're not that expensive. In the meantime try removing the cap on the cylinder you're fighting with, it should just unscrew, and snip off 1/2'' of plug wire then reinstall the boot. This assumes you have the hard plastic boots not the rubber ones that you need to crimp the connector to. Check this out:
http://www.z1enterprises.com/catalog...S750B-1977-IG0

[Killer2600]

Is it me or does anyone else find it strange your trying to do plug chops to adjust the pilot screws when you have a colortune?

[hampshirehog]

Check the compression on #1. You might have a dodgy valve seat (I'm assuming you have adjusted the valve clearances). She could be running fine when you have the Colortune in there but is missing when under load when you are riding on the pilot circuit. Though I have never come across this with Jap 4s this is quite common on Triumph twins with Amal carbs.

[whiterabbitt]

killer2600, I use the colotune to get real close and plug chops to get spot on under load, since I have no dyno and dont want to waste my brakes.

I will check your suggestions guys and let you know how it goes.

[rapidray]

Pull out the mixture screw on #1 to make sure it isn't broken off in the seat. Ray.

[whiterabbitt]

well as of yesterday the screw wasnt broke off. also trimming the plug lead didnt help, havnt got to the valve check yet. im thinking its electrical and not carb soo, I will be going there

[Killer2600]

Are you pilot jets the same in all the carbs and do all the carbs have all the same internal pieces in place as well as the same float level?

[1948man]

Within one set of carbs, yes. Different sized carbs will have different pilots.

[whiterabbitt]

PROBLEM SOLVED (I think): the problem turned out to be the points for 1-4, the contact is so burnt that there is a distinct x in the movable arm and after a bit of attempted dressing I know I need to get a new set. I guess I didnt get them properly cleaned last time i set the gap, cause they werent like that then. lesson learned.
I'm wondering why the #4 isnt displaying the same symptoms though