sailrider wrote:

Can you tell us all HOW you determine what your AFR is for each circut and what device / meter are you using ?


I use someone that has a portable dyna, which he also uses the "sniffer". All that a "sniffer" is, is an oxygen sensor shoved into the tailpipe. And thru the wonderful world of electronics, the sensor takes those gases, and the electronics converts that all into voltages, and the voltage reflects the Air/Fuel ratio. 14.7 afr is ideal for combustion, that is the proper ratio of gas and air. 14.7 does not reflect the voltage tho, there is still a bit of electronic wizardry that makes the numbers for afr. 14 is the leanest afr that my bike runs, and that is at cruise speed (65, 70mph max and 50mpg)after that my carb starts to go richer, at WOT my afr is aprox 12.5. At a constant 80mph I'm at 40mpg. I can set this carb to get 45mpg at 80mph, but I have no need to, seldom do I run at that speed for any length of time. another thing is my set-up, if doing 80mph in 5th gear, I don't need to drop a gear to pass, if I set it up for 45mpg @80mph, I would need to drop a gear to pass. I've played quite a bit with this carb, probably at least 20 to 30 different jettings, and have seen how the bike performs, and where the AFR's were. I've also spent a number of hours on the phone with the head tech over at Mikuni, and as well as Bob Yost, and have gleaned quite a bit of info on this carb, the biggest issue were neither one of them was familiar with this carb on the Roadie, both are HD guys. My biggest help was that AFR table in the article I mentioned. I've also ran this carb at a 13 afr for cruise, and with a 1 point difference in afr at this point there is a seat of the pants difference in performance from mid to wot, but at only a half point difference (@ 13.5)could not tell by seat of the pants.