Help me read these plugs!

[birdog4549]

I put some " cocktail shaker" mufflers on and left intake stock for now. The bike runs fine it seems but the plugs are trying to tell me something. One is black with a sooty look and the other is gray/white! Pilot jets? They are the same now as for turns out from bottom. Would out of balance do this (one side doing more of the work). Can you suggest a gameplan?

 

[angus67]

Use the dead cylinder method to tune it .they are very close.
Think of the motor as two motors working together. One cylinder may need more/ less than the other when its that close

 

[5twins]

I would check float levels and yes, check the carb sync. I would also check the spark plug cap and wire connection on that side with the dark plug. If it's loose or dirty, maybe you're getting a weak spark on that side. You could also swap the plugs side to side and see if the dark side changes (follows the plug). It's rare but not unheard of to have a bad spark plug.

 

[TwoManyXS1Bs]

Wipe off some of that dark coating in your left muffler with your finger.
Smell, feel, taste. Rub it on your cheek. How does it feel?
Oily? Or dry/sooty?

 

[eman13261]

Definitely do as mentioned above, this is a nice guide that I use. If so else fails make sure the pilot/main are the same size in each carb. I've taken apart carbs before that some idiot used different sizes and resulted in a similar situation. General rule of thumb wet=rich, white/sooty =lean

 

[eman13261]

Definitely do as mentioned above, this is a nice guide that I use. If so else fails make sure the pilot/main are the same size in each carb. I've taken apart carbs before that some idiot used different sizes and resulted in a similar situation. General rule of thumb wet=rich, white/sooty =lean

Also, since you put new mufflers on make sure all connections are airtight. A looser muffler could make one side run leaner than the other

 

[grizld1]

Help you read your plugs? Why, sure! Go to www.strappe.com and click the button for Gordon Jennings' classic article on plug reading. Warning--there's risk of injury due to exploding myths, so forget everything you think you know before reading the old master's work.

 

[mrtwowheel]

Help you read your plugs? Why, sure! Go to www.strappe.com and click the button for Gordon Jennings' classic article on plug reading. Warning--there's risk of injury due to exploding myths, so forget everything you think you know before reading the old master's work.

Gordon's article is in Tech Tips on that site.
Ah, the great Gordon Jennings, I miss those times and Cycle Magazine.

Yeah, use the dead cylinder method, I learned that from a Chilton Motorcycle Manual, and it works great on these bikes. Yeah, Chilton used to publish bike manuals, they were very general, but all of the necessary info was in there if you had some previous experience with bikes.

Scott

 

[grizld1]

Yeah, Wheel, but what I miss more about those times is being young enough to do crazy stuff and survive the consequences. Right--Gordon Jennings combined hands-on technical mastery with mastery of the written word and concern for clarity and accuracy; if Jennings wrote it, you could depend on it. That's a far cry from the likes of Joe Minton, whose work was full of errors, omissions, second-hand information, and grandstanding.