Did a Dyno run. Getting near perfect 13.5 AFR. Jetting is 162.5 Baron Needle/washer/clip 3rd groove/spacer/2 washer. Maxmix PMS at 1.75 turns out. Alt at 4500ft ASL.

To me with the near perfect AFR I should be getting more than the 31-32 MPG I get.

If your AFR is showing 13.5 where else would you be looking to get better MPGs?

I can scan my Dyno run from last year if needed. I haven't changed anything as I figured that was the best I could get with a great AFR line but continuing to read I should be able to get 40mpg at least I would think.

Sheepdog

If you want better mpg your cruise afr should be 14 or slightly above. Stoichiometric mix (perfect mix) for a gas engine is 14.7. I did some reserch on the cruise afr for a new Victory Cross Country and they are going as high as 15 AFR at cruise. But that is also FI and computer controlled. For our air cooled carbed engine you should be in the 14 or so area at cruise and about 12.5 at WOT. The dealer will try to set you up at the 13.5 that you are at. But your MPG will suffer.

make nice easy starts and quit blipping the throttle.. the accelerator pump is probably what is killing your mpg......

13.5 is a bit lean for WOT, better between 12.5 to 12.8 when throttle at 3/4 to wot. the richer mix helps to keep heads cool and prevent detonation. At cruise anything between 13 to 14 is good (cruise according to Mikuni is at 65mph, straight road, no winds. cruise is on the pilot ckt usually less than 1/4 throttle. when I had a 13afr was yielding 40mpg at 14 yielded 50mpg. Something is not right if you are getting in the 30's with that afr

Well update. I pulled my plugs to swap them for Iridiums and they were coal black and sooty as hell. I HAVE to be running rich.

My Filter housing has 6 1.5 inch holes drilled in it. 3 to the front side and 3 to the back. They have plastic pretty restrictive "grill-like" covers in them. I suspect the PO did the poor mans BAK on it and had it re-jetted.

I am guessing that I either have to rejet to lean it out or can I pull the grill covers to allow more air through the K&N filter. If this allows it to pull more air, would that lean it out some and would I gain more power from doing so? Could that tap up the MPGs a bit also?

Sheepdog

PS this is the third season that I have had the bike and but the first that I am doing all the work myself on her. So please forgive my ignorance to all of this.

What was the lowest AFR reading your dyno showed at WOT? Also what size pilot jet are you using?

You don't really need those grilles in the holes. Nothing they would stop can get past the filter inside. My "poor mans BAK" is a K&N filter in the stock housing with the lower half of the housing cut off.

Flashback wrote:
make nice easy starts and quit blipping the throttle.. the accelerator pump is probably what is killing your mpg......

I'm getting 42 to 45mpg everyday. And yes, I run her hard thru the gears on occaision....

So I yanked all 6 of the grills and have 6 1 inch holes now Not sure if that will allow more air in and lean it up from the rich I seem to be running right now, but cannot hurt. I have pictures of the plugs but suffice to say they are all coal black. That with 32-33 MPG means I HAVE to be rich.

I do seem to have a bit more power and a deeper rumble. Also she is start easy as hell. Also seems to be running less enricher to keep going cold.

Odd thing I noticed today was a "bloop" type sound from I believe the rear jug pipe. Hoping that isn't a precursor to SVS

So I guess I'll run a few tanks and check the plugs to see if they are clean or blackening up again. If so I guess I get to go into the carp and look at the jetting.

I am going to fully remove the carb next weekend and get all the jet sizes and list it all so I have a known starting point.

Sheepdog

Probably unrelated, but thought I'd throw it out there. Last week I started hearing a "bloop" sound from my pipes, too, usually on decel but sometimes at idle as well. My mileage was sucking pretty bad as well. Put the bike up on the lift tuesday, started it up, and noticed gas dripping from the bottom of the air cleaner, and occasionally from the overflow on the carb. Long story short, the o-ring on the float valve seat had cracked and started leaking, even with the float needle close, so was running super rich whenever I was off the throttle.