Plug Chop - Plug Read Please!

Cut the engine at 65MPH, pulled the clutch and coasted into my driveway and pulled these suckers out.



I'm thinking 1 and 2 are rich and 3 and 4 are in that safety zone, but could maybe be leaned out too.

What do YOU think?

 

Actually, I think those are pretty darn good!

 

I'll second that. At most, #2 just a tad richer than 1,3 & 4.

 

Have to agree I think they look good but I like a slightly rich mixture..

 

give 2-3 & 4. 5 degrees of enrichment.

 

I would leave them babies right-smack-dab where you got 'em!

I'd say, from the looks of things ... your bike is running real good.
You got some nice crisp Throttle Response and the thing probably Idles without a hiccup.

Tell us all what YOU did to get dialed-in like that.
Did you do a Colortune?
Is that the result of a few "Chops"?

Runs like a SportBike, huh?

 

What Rick said! Those look pretty envious to me...

 

Throttle response is great and the idle is rock solid once I get the bike warmed up, especially after a little bit of riding.

No colortune, here. I followed YOUR tuning advice in countless threads on here from beginning to end.

I started by setting the mixture screws three turns out and put on about 20 miles or so of spirited riding. I cut the engine at 65MPH, pulled in the clutch, and coasted to a stop on the side of the road where I had a backpack filled with tools ready to remove the spark plugs. They were lean on all four. Very lean. I backed the screws out about a half turn on all cylinders and went for another ride, killed the engine and repeated the process. Got a little color in the plugs, but still lean. Another half turn on all four hoping I'd make this bike rich. I was right. Plugs were a dark brown at the next plug chop, some moreso than others, so I adjusted accordingly, in DEGREES this time! I did one final plug chop and that's what you see in the picture in this thread. I went a degree leaner on 3 and 4 and about 2-4 degrees on 1 and 2 (I've got a water cooled bike, so I figure I could afford to run a bit hotter). I haven't chopped with the current settings, yet, but I may do so today.

I would say the best part about doing the plug chop out on the road is when you get some friendly neighborhood people to stop and ask if you need any assistance. "Nope, just trying to tune my bike the old fashioned way!"

I should also note that my engine and carbs are in tip-top shape. I replaced the butterfly shaft seals and mixture screw o-rings as well as the o-rings on the intake boots - basically anything that could draw in "unmetered" air, as we call it in the fuel injection world. My carbs both bench synced and tuned on the bike with it running.

Overall the bike runs great. I still have an issue to iron out at idle, but I think it may be an ignition issue rather than a carb or tuning issue. More tinkering and tweaking will reveal that mystery.

 

Is 4 turns out a touch too much Rick?

 

If I had to estimate, I would say that I'm between 3.75 and 4.50 turns on each cylinder.

I thought it was too much, too, but I'm not really going to argue as my bike is running great and the plugs look pretty good, too

 

Go with what works don't worry how may turns...

 

It would seem to me that at 4-Turns out the Pilot Mixture would be wide open.
That, of course depends on the Pilot Mixture Screw, itself.

Some Models have Ultra-fine thread, while others have a Thread Pitch a little less fine.
I also noticed that the design for the Metering end looks different on the replacement ones that I have had to use in place of ones drilled-out.

The new ones have a taper to them rather than a shouldered area just above its tip end.
If the Screw doesn't feel too loose and you are not worried about losing it, I guess 4 Turns out is where you need to be.

If you begin losing the tuning from being so far out and the Screw winds-up changing it setting due to vibration from not enough tension on the Spring; then you may have to increase the Pilot Jet size and adjust the Mixture screw down to where the Spring has a limiting effect on its movement.

Maybe what I'll do is try to create an Illustrated Pilot Mixture Screw visual by removing some of the stock on a Carb Body with broken Float Hinge Pillars so we will have a view of where the Mixture Screw's end is in relation to the Intake and O-ring from the side.

I haven't seen anything but confusing drawings in that regard. Plus. it would be a project I could do in the comfort of a heated family room rather than the cold garage, this Winter.

 

WHERE ARE THESE ADJ SCREWS LOCATED, JUST GOT BY BIKE AND HAVE NO MANUAL OR PICS.

IM IN THE COLORADO HIGH COUNTRY, ALT HERE IS ABOUT 6000 FT..
SO IM GOING TO DO THE DRIVE N CHECK PLUG CONDITION JUST LIKE YOU DID TO GET THEM RIGHT.

FOR HIGH ALTITUDE, WOULD YOU RECCOMEND SAME SETTING AS YOURS, JUST A BIT LESS THAN RICH, OR MABY A LITTLE LEAN ?

 

Wow. Nice plugs.

 

very "safe zone" plugs, those plug chops do wonders.

on the topic of idle..
the starter jets were cleaned when you did your overhall right?
and your floats are set correct?

 

The starter jets were cleaned and the floats were set.

It's about 30-40 degrees here during the day and this bike will startup cold without any choke and will idle right around 900 RPM. Even twisting the throttle produces zero hesitation. I'm confident its running where it should be, but I still have a leaky petcock to deal with...causes hydrolock if the bike sits too long.