Pighuntingpuppy
Well-Known Member
The 2007 has got something going on. Finally got the coil out as the weather finally played nice out. Quick back ground on whats going on. Bike starts normal. Will normally go through the gears without a hiccup. No misfires or stumbles. When you lay into the bike and get it into Vboost, it feels like its just lacking on the top end. It never breaks up. It never stalls. Fuel mileage is higher than normal. Normally around 30-33mpg. Last couple tanks, I am nearing 40mpg. Even giving it hell. One other thing I noticed. When the bike is at idle, the RPM is 900. Normally when it is operating temperature, it is 1000 RPM. I removed the air box, checked the slides and top air jets. Nothing seemingly out of place. Removed the spark plugs. The right front spark plug is fouled black. Remaining 3 are light tan. So....despite the lack of raw fuel smell and higher than normal fuel mileage, I removed the ignition coil. Since this is what I suspect at the moment. Tested the primary coil. 3.2 ohms. Specification is 2.7 ohms. I will take this as an acceptable reading as temperature may not be exactly as the manual states. The secondary resistance is 13.17 K ohms. Specification is 13.2 K ohms. Again, I will take this as an acceptable reading as temperature may not be exactly as the manual states.
I may be overlooking something as generally when I see something that looks off, I can usually determine if its fuel or spark. I black spark plug tells me that I am getting either too much fuel or not enough spark. Since my fuel economy has increased....at this second, I would tend to overlook the carbs as the guilty party. But I know it could be. Same thing with the ignition coils. They may be the guilty party.
These are the symptoms, which is what I detected from this particular point. Spark plugs were installed earlier this year with NGKs. The Yamaha dealer did a valve adjust and carb sync less than 18 months ago. I know these mean squat in the grand scheme of things but its the history I know. What would be the next course of action to look at?
I may be overlooking something as generally when I see something that looks off, I can usually determine if its fuel or spark. I black spark plug tells me that I am getting either too much fuel or not enough spark. Since my fuel economy has increased....at this second, I would tend to overlook the carbs as the guilty party. But I know it could be. Same thing with the ignition coils. They may be the guilty party.
These are the symptoms, which is what I detected from this particular point. Spark plugs were installed earlier this year with NGKs. The Yamaha dealer did a valve adjust and carb sync less than 18 months ago. I know these mean squat in the grand scheme of things but its the history I know. What would be the next course of action to look at?