After a few mods, the gas mileage on my 06 Road Star has gone from 42 to about 30 MPG. A few weeks after I bought the bike I put on a set of 3” Hard Krome Straights. With this mod I was still getting 42 MPG. About a week ago (after a long wait) I added the K&N drop in filter. With this mod the bike was still getting 42 MPG. One week later I took my bike in to be jetted (.175) and the AIS removed. That’s when I noticed the drop in MPG. At first I thought it was due to my driving so I slowed it down but I’m still only getting about 30 MPG.
After reading some comments on the grade of gasoline to use, I am on my second tank of 87 Octane to see what difference this would make.
What can I do? Thanks

What jet kit was used & was the carb/PMS adjusted in anyway?

That I do not know. The shop where I bought the bike did the work. I will find out on Tuesday when they open. BTW - just filled up again 118.7 miles took 4 gallons. THANKS!

SAME HERE PUT ON SHOGUN LONG CANNONS AND GOT aboiut the same mileage then put in dyno jet stage 1 kit with the 175 jet they recommend, turned the mixture screw in till it seated then turned it out 3 turns just like the dyno jet instructions said to not the 3 1/2 recommended b y instructins on this site and blocked the air tube andf yesterday went on a long highway ride 177 miles on 4.8 galons which equates to 36.8 could have swore i was getting close to 40MPG Any one out there with a bone stock 04 or 05 road star have any MPG info thanksd any help is appreciated

MY-STAR-1,
Yours sounds about right, remember when you make modes to increase performance you usually give up some MPG's. My '05 Roady was getting 43-44 mpg stock. When I put on the Vance and Hines powershots, air cleaner kit, removed the AIS, and jetted (190 main, "c" clip on 2nd notch and PMS at 3 turns) I'm getting about 38 - 39 mpg with 87 octane. By the way I am in Balto. Md. at only about 200 ft. above sea level, your jetting may be different. As far as BlkDakDave, your mpg sounds WAY too low. When I first jetted mine I was way too rich, only getting about 28 mpg. This may be your problem also. Most jet kits come with instrutions and quite a few "mechanics" will just follow those instructions. You really can't do that, the instructions are just a starting point so the bike will run relativly okay. In most cases you need to keep adjusting and testing until you get the right settings. Unless you have a mechanic that works mostly on RoadStar's in your area it will be very hard to get it right on the first shot, even the Yamaha dealer won't be able to do this. Good luck, Ride Safe.

I agree with geezer on both of his recomendations.

MY-STAR-1, your mileage is lower than I would like mine to be, but you are very close to being in the sright spot. Getting it better will mean playing with your carb circuits, and the balance between them until it come out right.

If you want to pursue that, I would suggest you create a new post in the jetting folder and see if you can get some recommendations on where to start. Be sure to post all relevant factors, ie: main jet brand and size, needle brand and c-clip setting, pilot jet size and brand, baffles in pipes or removed, manifold proted or stock, brand of air kit (or if stock just say so).

Also, if you get help on that, stick it out. Getting from your surrent settings to something slightly better may take nothing more than dialing in your PMS, or might take more than that.

To geezer's point, the recommended settings in your kit are only a starting point. Its going to be up to you to optimize them to your own satisfaction.

BlkBakDave:

Your mileage is too low. You are clearly rich somewhere in the power band. If you can get the jetting settings you currently have and post them, someone will most likely be able to help. Be sure to post all the items I asked MY-STAR-1 to post so anyone helping can get a sense of everything that is involved.

GRAM

by PMS setting do you mean the screw that i removced the brass cap from then turned in till it seated and then backed off three turns?

Yes, thats it.

You might want to look for the article 'Dialing in your pms' in our tech tips section (under the carb section). If you feel like messing around with it, it might help improve your mileage a little.

GRAM

OK whats the deal here, going to go back in my carb to check my work and choke and make adjustment on PMS screw. First i decide to loOk at original main jet and with a magnifying glass and some good squinting i read on it 182.5. now i replaced it with a 175. I was under the assumption (MOTHER OF ALL SCREW UPS) that the higher the number the bigger the jet. Was I mistaken if so should I reinstall the main jet back in the carb? signed confused but not lost LOL

Mystar1, you're right about your stock jet being a 182.5. Too rich for the stock set up. Are you running a BAK or other open air kit? When you install a Barons needle/jet kit, they recommend to start with a 172.5 and start dialing in the carb. And yes, the higher numbers equal larger mains, pilots...but not all jets are created equal, number-wise.