Is there a break-in period for plugs when checking your mixture screws

[thomasj]

Question about Spark plugs color and mixture screws

I put new spark plugs in and rode down the road in 4 th gear about 5,000 rpm for a few miles pulled the clutch , flipped the kill switch and rolled to a stop. I was looking for the golden brown look after seeing the spark plug chart and they looked a little white or grey . I'm 200 ft above sea level and running the stock 152.5 main jet and stage 7 needle 3rd clip from the blunt end, Morley air box/kit , Marks exhaust and I was at 2 turns out on my screws which don't really feel too lean but feels very crisp and pulls very good. I just wonder if the plugs are too new to read accurately . Do I need to ride longer on these plugs to get a more accurate reading ? I then turned them all out a half a turn more and rode home because it was almost dark and the bike just don't run as crisp. Also the bike i have has the old 3 stage v boost switch where you can flip the switch and the vboost is open. When I have the mixture screws at 2 and flip the switch to open the v boost it idles and sounds perfect. I feel that if I dont hear that rump rump sound its probably getting too much gas. I could be wrong about that ? Ill add one more thing, when I turn the mixture screws out and try to listen to the engine sound to get the screws close I cant really hear any different sound until I have the screw nearly all the way in. Ive even turned the idle way down to where it nearly shuts off to listen for a change in sound but I cant really tell a difference. My main question here is about the plugs but if anyone has any thoughts I'd like to ear them. I may turn the screws to 2 1/4 turns and ride it for a while and then check it again

 

[sdt354]

I think a throttle chop on new plugs is good. That way old issues aren't read. Not getting response from the A/F mixture screws is often due to the sync being off. But dirty circuits can cause that too. I like to sync 1st at a low rpm, then adjust A/F screws with good sensitivity(ear method), then set idle speed up to 1600 rpm and sync again, then set idle rpm back to 1100 rpm. This gives me a nice crisp throttle response. I think the leanest A/F setting, where you run just as well, is best. Mine likes 2 1/2-2 3/4 out from seated. When done, my sync at idle will be a bit off and the rumpity sound is happening.
Steve-o

 

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Light gray plugs are pretty normal on a vmax that is tuned right. Don't be overly concerned with the plug color. Vmax runs best a bit lean and you would be hard pressed to find a thread here on the forum of someone doing damage to their engine by having the carbs tuned too lean.

Pay attention to the way it runs. The bike will tell you what it likes.

Your jetting sounds right in the ballpark compared to many others on this board are running considering your altitude.

 

[Dragmaxster]

Your answer is "no" they don't need a break-in time.

 

[Woody]

you can't get a good reading on new plugs.
i would read an old set, address any problems. then do the new plugs.
by reading plugs, your checking fuel air mix.(jetting) or if a float is sticking. looking for rich or lean conditions.

 

[thomasj]

I think a throttle chop on new plugs is good. That way old issues aren't read. Not getting response from the A/F mixture screws is often due to the sync being off. But dirty circuits can cause that too. I like to sync 1st at a low rpm, then adjust A/F screws with good sensitivity(ear method), then set idle speed up to 1600 rpm and sync again, then set idle rpm back to 1100 rpm. This gives me a nice crisp throttle response. I think the leanest A/F setting, where you run just as well, is best. Mine likes 2 1/2-2 3/4 out from seated. When done, my sync at idle will be a bit off and the rumpity sound is happening.
Steve-o

I sync with the carb tune at about 1100 but I haven't tried 1600 and then back down. I want to set mine at 2 1/2 like I keep reading but it just isnt as good. I was just concerned about the plug looking greyish white and the ground electrode (bottom of plug) looking white-ish. Thanks for the tips !

 

[thomasj]

Light gray plugs are pretty normal on a vmax that is tuned right. Don't be overly concerned with the plug color. Vmax runs best a bit lean and you would be hard pressed to find a thread here on the forum of someone doing damage to their engine by having the carbs tuned too lean.

Pay attention to the way it runs. The bike will tell you what it likes.

Your jetting sounds right in the ballpark compared to many others on this board are running considering your altitude.

Glad to hear that . It sure runs great where its at. I can tell when moving the clip on the needle when the bike has been too lean.. you just know. But when I saw that grey even the ground electrode (bottom of the plug ) is whit-ish I got a little worried. Thanks for the help bro !

 

[thomasj]

you can't get a good reading on new plugs.
i would read an old set, address any problems. then do the new plugs.
by reading plugs, your checking fuel air mix.(jetting) or if a float is sticking. looking for rich or lean conditions.

Yep, That what I'm going to do. I'll going to ride on these a while and then pull'em . thanks !

 

[Vh5150]

My bike is the same way. I tried setting the A/F at 2.5 turns out and it doesn't run quite as well. Also had a little more soot in the exhaust tips. Set them at 2.25 turns and it runs great. Even then exhaust tips are a little more grey colored on the inside. New plugs look the same as you described. It seems to like that setting so I think I'll leave it.