Ok, I'm running a 45 idle and 180 main, A/F mix screw out about 2 1/4 turns. I get a little bit of decel pop, and my pipes have minor sooting in them... not heavy. My front plug just has one spot on it that is starting to show some tan coloring to it. I have about 200 miles on these plugs now... should I richen it up some, or am I good to go? Just don't want to burn a hole in these pistons. I don't see how that could happen though, considering from the factory this sucker came full advance, with a 42 idle and a 170 main jet.

 

Your in the ballpark....If the Electrode, Earth tag or Porcelain were all black then I would be telling you your too rich.

Your definitely not too lean so thats a plus...too lean and you would not see as much carbon.

Its always going to be a trade-off on the Pilot jet to get a balance between minimising exhaust popping on deceleration and running at perfect mix - I choose to run richer and cut down on the popping.

Your main jet is in the right ballpark as well, so I would just ride it!

 

i have stock motor with ev27 cam screaming eagle air cleaner i put a 190 main 48 slow jet mine is a 91 the carb doesnt have the plug for air mixture

 

I kind of figured as much. On my mx bikes I got good at reading plugs (before the time of ethanol) but with this ethanol gas, and my lack of experience with these evo's, I'm just making sure I'm safe.

 

Does it stumble and choke out when you turn the idle mix screw in past the 2 1/2 turns and bog down when you turn it out past the 2 1/2 turns? If it does, you probably have the right slow jet. If it doesnt choke out when you turn it all the way in you probably are a size too large, if it doesnt bog down/out when turn it out 3-4 turns you probably are a size
too small.
As for the main jet, get the bike out on a road you can run at speed safely on. Get it in 4th gear and run it up to redline, then slightly back off the throttle. If the engine wants to run faster when you ease off it's probably too lean. If it responds accordingly your probably gtg.
How is your throttle response? How is your needle set up?

 

CVP needle shimmed with 2 small washers.

No cough, no stumble... run up to redline, chop the throttle, and it immediately decelerates, no hesitation, nor surging... wack the throttle and she just goes, ZERO hesitation like it had with the stock cam and the jetting set up I had.

EDIT: I forgot to add that it does kind of bog a little when you run the A/F mixture past the magic number of turns, and coughs a little when you turn it in. But as far as riding performance, like I said, no cough, no stumbles or hesitations.... it just goes and decelerates.

 

My plugs look about the same as yours, my jetting is the same as yours. The only difference is I don't have the needle shimmed (but have the cvp needle for big twins), and I don't have a cam.

I get the decell pop as well, but only after I really get on it and then let the throttle drop to idle position. I have replaced manifold O-rings, and exhaust gaskets, along with using silicone to seal up the muffler to head pipe connection point.

I think the decell pops is the nature of the beast with the mufflers I run. I run the cycle shack mt-129 mufflers and they are short.

What kind of exhaust are you running? YD

 

I had decel popping on a friends bike as I had set the idle a little low,adjusted it back up and ok.

 

V&H competition drag pipes with the baffles in... should be no leaks, new james exhaust gaskets, new intake gaskets, everything tight.

I think I'm just going to call it good and fine tune the timing and jetting later when I can get it on a dyno.

 

Showing a plug set with a AFR reader at some good numbers. You are still slightly lean but in the power range, heat can be your friend but can also be your enemy. Most likely need a little more needle because that is where it spends most of it's time and more color needed on the electrode.

Your timing heat line should be in the center of the strap bend also, can tell if timing is advanced or lazy.