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Tune up question

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rollo3076

Active Member
Hey folks, thanks for this great forum. I have 08 egc with stage one upgrade, hooker true duals. I usually change spark plugs every other oil change. I notice the fuel mileage has fell off a little, and sometimes it just does't seem to be running right. No missing out or anything, just sluggish. When I changed the plugs this time, it seemed the rear cylinder didnt burn as clean as the front. I was wondering what is invovled in a tune up, other than plugs. Do I need to have it put on the dyno? From what I've read here, I'd rather not. Any helpful suggestions are appreciated. Thanks guys.
 
Put old plugs back in and run some Sea Foam through a tank of gas. Then change your plugs and see. Are you using factory stock HD plugs???? With the upgrades done is there also a fueler of some type added to make up difference in leanness????
Nexa on the dyno in my opinion....
 
Only a stage 1 download to the factory ECM? Has the fuel mileage fallen off. If you hold WOT in a tall gear (5th or 6th), does the bike feel like it is running out of fuel or nosing over. Have you manually checked for any possible DTC codes.
 
yessir, harley plugs, no fueler. How much sea foam in 6 gallon tank?

Yes stage one to factory ecm, mileage has fallen off. There is no problems at full throttle. No codes.
 
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Just a shot in the dark.
Almost sounds like a weeping, poor spray patten on rear injector. That would post no codes, ruin the low RPM smoothness and performance, hurt your fuel mileage, make rear plug read off from front plug, and would not affect your WOT performance.

Either that or your using HESS gasoline!:)
 
Will the sea foam fix that or do I need to put something in the gas to clean injectors?
 
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In a dark garage, Start the bike, cover the headlight to block that light, Then after your eyes get accustomed to the dark' check to make sure that your spark plug wire aren't arcing. You might have to rev the engine up and down a few times.
Changing plugs that often can weaken the wires.
 
rollo3076 said:
Will the sea foam fix that or do I need to put something in the gas to clean injectors?
Click to expand...

I can only say what my experience has been. I have found that once an injector is clogged or the spray pattern is poor, tank additives really don't work well at cleaning them. It's almost like you have to run cleaners from the get go in order to maintain a clean system. But then again the other side of the coin is, I would never continuously use true injector cleaner either (Techron etc) because it will work it's way into the oil.
It is really a catch 22 topic in my opinion. I no longer use any true fuel injector cleaners, especially Techron. But if your someone that does,, be sure to follow the instructions. Don't use it too frequently.

My view point on this topic is way different today than it was 20 years ago. Today I would just spend the $150, buy a new pair of injectors and replace both.
There are also injector cleaning services that will ultrasonically clean the injectors under pressure, check the spray pattern and flow bench them for volume for a reasonable price. The thing is the turn around time puts the bike out of commission.
 
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