What's your guess on sudden fuel mileage drop?

[atokad]

Seems I have pretty much have gone from a consistent 48 MPG to a consistent 40 MPG basically from one tank to the next.  What do you think would cause that?
2006 - 23k miles
New plugs, air filter and TB balanced at 13k miles. Standard airbox, no mods. Ok, so I put on a few pounds, but come on, that can be it. 

My first thought is fuel filter since I have not done that yet.  Probably try and test in this order.  Fuel filter, air filter, then plugs. Last guess is winter fuel blend??

Anybody else had first hand experience with this sort of drastic MPG change?

[Mustang]

can't say for certain .but the crap they are trying to pass for gas these days is bad ,really bad .
I have noticed the wife's Toyota Yaris has gone from 38 to 32 mpg this winter and my Nissan truck has gone down to 11-12 mpg from 15-16 mpg
my brother has noticed the same with his vehicles also . haven't been able to check the bikes as the temps here in the frozen wasteland have not been warm enough to get the bikes running full time yet .
these drops in fuel mileage were pretty sudden also for us .
I blame the gas with ethanol . Oh how I miss the days of 104 octane ethyl 
see if you can find some gas that isn't blended with corn squeezin's before you blame the bike .

[Sin_Tiger]

One thing is sure, it won't be because you are using the demister a lot more 

[blacktiger]

from a consistent 48 MPG to a consistent 40 MPG basically from one tank to the next.

I agree with Mustang. Change your fuel first.

[Bixxer Bob]

The EU are threatening to increase the amount of green in our fuel over here......

[HockleyBoy]

Seems I have pretty much have gone from a consistent 48 MPG to a consistent 40 MPG basically from one tank to the next.  What do you think would cause that?
2006 - 23k miles
New plugs, air filter and TB balanced at 13k miles. Standard airbox, no mods. Ok, so I put on a few pounds, but come on, that can be it. 

My first thought is fuel filter since I have not done that yet.  Probably try and test in this order.  Fuel filter, air filter, then plugs. Last guess is winter fuel blend??

Anybody else had first hand experience with this sort of drastic MPG change?

My 06 with very similar milage has dropped off a bit recently (was 200 miles to fuel light now 180 to 185) I am going to start with a reload of the fuel map as mine seemed to change soon after a battery failure so I am hoping it is a simple as a corrupt map.

Might not be helped on mine by valve clearances, filters etc as am rapidly approaching the 24k service.

[atokad]

Thanks for the replies.  Here in Colorado all of the fuel is 10% ethanol.  Our octane choices are 85 -87 -89.  Crap for fuel.  I have been riding a bit more this winter than past and taking longer day trips than normal for me.  Fuel light used to come on around 225-235 miles. Now I see it at about 195-210.  I believe there may be ONE gas station in all of the Denver metro that sells fuel w/o ethanol in it.  I have read somewhere on ADVrider of a place that guys go to get race fuel w/octane of 105? 110?  Something crazy high like that.  Maybe I will seek it out.

Thoughts on the fuel filter?  Have you all done it by about 22k miles or is someone running way past that with the original yet?

Mustang - come West, pretty much can ride all year.  Then I will have someone local to help me with valves the next go-round.       This was yesterday.

[chappers]

sod the fuel ..... nice pics......

ive noticed the same thing , but  ive found a solution , in a store in the uk called b and m they sell an additive that puts the good stuff back into ur fuel and all for just over 2 quid .

[blacktiger]

Thoughts on the fuel filter?  Have you all done it by about 22k miles or is someone running way past that with the original yet?

It's supposed to be changed every 12K miles. FYI it a common part on BMW and others and you can find it cheaper than at Triumph. Like :- http://www.squaredeals-ltd.co.uk/triumph--mahle-fuel-filter-kl145-metal-cased-replaces-triumph-part-t1240850-1612-p.asp

[atokad]

Thoughts on the fuel filter?  Have you all done it by about 22k miles or is someone running way past that with the original yet?

It's supposed to be changed every 12K miles. FYI it a common part on BMW and others and you can find it cheaper than at Triumph. Like :- http://www.squaredeals-ltd.co.uk/triumph--mahle-fuel-filter-kl145-metal-cased-replaces-triumph-part-t1240850-1612-p.asp

Yeah, I got the part number from one of Stretch;s posts.  Have it written down and will probably get it this week.  Just going to do one thing at a time and see if I can localize what the issue was/is.  Although if the fuel changes to a summer blend soon it maybe harder to determine, but the filter is due I suppose.

[Sin_Tiger]

sod the fuel ..... nice pics......

ive noticed the same thing , but  ive found a solution , in a store in the uk called b and m they sell an additive that puts the good stuff back into ur fuel and all for just over 2 quid .

Do share your experiences please 

[chappers]

i really cant remember its name but iam sure it is an octane booster , and it really does say  what it says on the tin. i tried it on my 4x4 and it works a treat. next time i pop there ill get more details on it.
and it was around the £2.30 mark