hey my bike when full gas was reading 230 to empty now when i fill it up is say 204 i did put the bike the shop they found it was ok . but to me it not help

 

So, what is the real problem?
You have to realize those fuel mileage calculations are not and never will be all that accurate.
They are intended to give you an estimate only.

Also realize that whatever number is displayed will be constantly changing based on current conditions encountered.

 

I have found that what the guage reads is directly a result of how you rode on the previous tank of gas. I've noticed that when I ride back roads around 45 mph or so the next tank goes up as high as 265 but when I ride highway miles around 65 to 75 mph it will decrease to around 210 to 220.

 

yes i was geting 180 or more out a full tank but now 160

 

Same fuel? 10% Ethanol will cause a drop in MPG. Weather can affect it as well (especially wind).
I don't trust gauges much and usually fill up long before I have to, when it's convenient for me.

 

Fuel up at 204 then, what up?

 

The remaining miles left on tank are based on the current fuel usage.
If you ride at 75 MPH+ and/or do a lot of idle and stop/go, the reading will be lower.
If you ride at a constant lower speed, or ride easy off the line and not fast, the reading will be better.
I have had the reading as high as 295 miles remaining on tank after fill up. But I had been riding on a highly patrolled divided 4 lane road at posted 55 MPH speed. I got great mileage, but took forever to arrive. But, it was a great look at the trees and scenery.

So just use the "Remaining Miles" as a guide to how you are riding, not as Gospel.

 

I have an 08 ultra,get lil bit over 200miles on a tank.

 

I agree with the ethanol lowering the mileage.

 

I just took a 600+ mile ride on my ultra. Checked g/mileage every stop. It went from between 37 and 46 mpg. I haven't worried yet.