Too rich, too lean, just right?
 

Took my first long (300 mile) sustained ride yesterday since Ive done the winter mods. Ive got a K&N filter, sikpipe diesels with DK thunder torques and VIEDs cranked up about 3/4s on both front and rear cylinders. I noticed this at the end of the ride. Is one too rich the other too lean, one just right? Before all the super technos start spouting off about its all bandaids and guessing........Im ok with guessing, Im not going to the moon so me and my bike will be just fine.

https://lh5.googleusercontent.com/-P...2/IMAG0291.jpg

https://lh6.googleusercontent.com/-N...2/IMAG0290.jpg

Did you pull the plugs to see it they are different?

that would be my first guess as well. How does it sound at idle? are both cylinders firing consistently? I know I have to run my rear cylinder with a closer gap on it.

Nope, havent pulled the plugs. If the plugs look similar to the pipes does that mean the rear is running rich? Or is the front running lean? And it seems to be idling fine.

I have absolutely nothing to contribute to your problem, but I wanted to say that every time I see a picture of your bike I think "Damn, that's badass!"

That must be a neat trick. How do you close the recommended gap of .040 by .5?

:icon_lolsign:


And yes, read the plugs, not the pipes.

to err is to human ;) thanks for the correction, once again. Apparently your breakdown of the speed of light is correct!

Ok, Ill do nothing till I read the plugs.

Your bike is screwed. Better just let me take it off your hands....

Bahahha.......I think your right. Ill deliver it to ya. Is hotdog near LA? (Lower Alabama)

Hmmmm... Either I edited my info after coming home late on a Friday night or that is forum default lol. I don't remember putting that in there

When did they roll on the throttle for the pull?

Ok, pulled the plugs, they look vertually identical. The rear was ever so slightly darker, wouldnt have noticed it had I not been looking for it. Front plug was gapped at .037, rear at .040

https://lh5.googleusercontent.com/-C...2/IMAG0295.jpg

I find that with these new EFI bikes it is not so good to try and get a read on the plug color. Putting a sniffer up the pipes is the only real way to see if the AFR is where you want it.

Another thing you can do is shoot the cylinder heads (right next to the spark plug) with a infrared heat gun.

btw, saw your scraped turn signal and footpeg in the other thread....bet that was fun!

The plugs look fine, maybe just a a bit lean, but typical for EFI.

+1, Just as said. If you'd like to compare them.....heres a chart.

http://www.dansmc.com/spark_plugs/sp...s_catalog.html


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By the little bit i know about color i'd say your front is running correct and the back is running rich,so you can try to swt the plugs around so the 37thou is in the back and the 40 in the front,like guitarman023 said he runs his rear spark plug closed.what the hell could be a cheap fix.As a matter a fact i just put V&H Shortshots on my 09 nightster1200 and if it starts to run funny i'll have a look at that trick.

the pipes look good to me...the rear a little rich, which is good because the rear cylinder gets less cooling so you want it a little richer to help it run cooler...

If it was me I would crank the ViED's all the way up.