Bike is 2006 Road King Classic with Stage 1 for 25 degree injectors, race use only, PCIIIUSb with custom dyno map and rush mufflers with 2.5 baffles. Prior to PC was averaging 36 mph running rich. After PC installed and dynoed average 44mph running better. Had an issue on startup this weekend bike starting skiping and poping black smoak. Checked PCIIIusb and map looked OK. Decided to remove PCIII and bike ran well, almost to well. Road 600 miles in two days, bike actually performed great, one trip average mph was 54mpg and other trip at higher speeds average 50mpg. Temp outside almost 100degrees and oil temps when at interstate speeds average 236 degrees running synthetic. My mileage has never been this good even with the PCIII. Something must have clicked in the engine but cannot figure out what or why. I did use to sea foam in the oil this past month. Is it possible I have had a seal or something that finally fell into place in the engine or could I have a potential problem?

Now my question is what would cause the engine to all the sudden change this way to where bike is running better and getting better mileage without PCIII USB. Any opinions welcome as to my mystery.[/align]

 

Your bike is sooooo lean without the PC thats why your getting 57 mpg...the 36 mpg with the PC would say the PC map was too rich. The reason your bike was blowing black smoke on start up is because the warm-up enrichment fuel was activated by the ECM and your PC has added fuel in that area too so now it's wayyyyyy to rich during warm up.
You need to put the PC back on and have it tuned and tuned correctly. Your bike is melting.

 

Doc,

I appreciate your information. I think i need to clerify. Bike was running way rich without the PC installed and was getting 36 mpg originally, note without the PC. Had bike dynoed by cycle solutions, load based dyno runs. PCIII map was custom made and bike was getting 42mph average after PC and dyno. Now all of sudden with PC still on no changes bike acts up. Took PC off now getting 50-54 mph and bike running much better. Something in the engine has changed. If originally before PC was installed bike was running rich at 36 mpg and now when I removed the pc because of sudden issues the bike is not running that same rich something on the bike or ecm or sensor or valve seat has to have changed. Rember bike was running Rich before PC installed and now after I am back to the way is was before PC it is now running leaner with no ecm changes. Hope this clears up my mystery. Also oil and engine temps do not indicate lean danger, bike is actually running better than it ever has..weird, any ideas

 

You should be getting around 42 to 47 with a good tune....57 mpg is telling me it's way too lean. The oil tem on the road should be around 220 to 260 degrees, 136 degrees i'd be questioning my temp guage or the oil isn't pumping through the motor.

 

Doc,
Meant to say 236 degrees. This does not make sense to me. If before the pc was installed the dynojet showed bike running way to rich, and after I removed the pc should it not go back to the original ecm settings which should be back to rich. This is my delima. after removing my pc with custom map bike gas mileage did not match what it was originally before dyno and pc3 install. It seems as the bike changed on its own.