Ive had my K&N cone filter and carb rejet done for a while now and never really paid much attention to my  gas mileage till this last tank full. I didnt even get 80 miles before I had to go to reserve today. That's less than 40mpg!!! I usually ride pretty hard but i tried to stay out of it some this time and see what the mileage was like. This sucks! Im just glad gas is only around 1.59 here. I have a 52.5 pilot in, 2 washers in the needle valve and a 152.5 main in the carb with the idle screw at 3 turns out. I cant go up on the pilot cause it runs way too rich even with idle screw all the way in. I also have a Jardine slip-on. So here is my question. What kind of mileage do you folks get with the cone filter and rejet done? Any suggestions on my jet sizes and needle washer amounts? Or do i just need to quit dogging it? (Like that will happen ) Im gonna pull my plug tomorrow and see what it looks like. Last time I had it out it did seem a little black around the outside with small amounts of brown near the center. I also thought about running some seafoam through it. Ive never done it before so i guess it couldnt hurt. Thanks for any help.

Mario

Jardine slipon, 152.5 mainjet, stock air filter, IR plug, 20w-50 vtwin mobil 1, gave ~54mpg with a '95 savage over 12k miles measured as a commute bike - seldom over 4k/rpm rare over 5k/rpm.

Only look at the insulator of sparky, if she's white, it's too lean.  Maybe so lean she's missing.

Mikuni (or Suk) said most of the time you're running off the pilot jet.

If that's true, I would richen up the pilot and lean out your main.  And add a washer to the needle jet.

Pre-tweaking, I got 54-56mpg on the freeway.  After the cone filter, HD exhaust, and rejet, I dropped to 46-50 mpg on the freeway.  I don't know of anyone who's mileage stayed the same, much less went up after they started fiddling with it.

in Baltimore area as a new rider, I haven't been watching my motorcycle mileage yet, but I know my car mileage very well.  The winter formula gas and colder operating temps have cut my mileage from 28 mpg to 23.5.  That is 16% worse!

i realize colder temps will have an effect on the mileage but when i was getting 50mpg before mods and now only getting 35mpg its just a little weird. i only expected about a 5-10mpg drop. well its still better than my truck which gets about 23mpg at the most. did i mention a hell of a lot more fun!!!

Went with 152.5 main, 55 pilot, 2 washers on needle, OEM air filter and fishtail exhaust with built in baffle, average about 49-51 mpg, down from 55-57 mpg stock, 20k miles.

well right now i have my carb torn apart and was gonna put an extra washer on the needle but i did not notice before that it has an adjustable needle. the needle is set to the 4th notch down from the top. should i still put the extra washer or just mess with the notches on the needle first? or should i do both? i also noticed that the washers dont go down into the small hole where you put the needle. are they supposed to or do they just sit on top of the small hole inside the diaphragm assembly? any help is greatly appreciated.