Gas Milage

[pancho]

OK,, since I got my bike, it has gotten just under 32 MPG, I check mileage every fill up.  I could count on it going on reserve at 130 miles. I've been through the carbs twice over the last couple of years, and have a variable ECT mod, and the gas mileage has always remained the same, maybe down to 31 when running full advance on the ECT. The bike has always ran well.
Now, with no noticeable change in performance that I can discern, for the last four tanks, reserve has been needed at 165 and the gas mileage has gone up to just a hair under thirty eight!! I'm not complaining, but what in the world is going on? Anyone run across anything like this before?

[Chrisj CMA]

Not a fuel expert but the blend changes for the summer.  Maybe that's part of it

[old2soon]

The right hand determines yer fuel mileage or lack there of. Are you going up easy thru the gears? NOT red lining every shift goes easier on fuel usage. Keeping tires properly inflated yields better fuel M P G results. On my I/S I've delved into the teens on M P G. Also gotten into the very low 40s. My real "average" is low to mid 30s. The sweet spot on R P Ms-do Not exceed 3ooo. But after I went thru my short list-I did NOT purchase my Valkyrie looking fer M P G-got er fer S P G-smiles per gallon. I getz lotsa those!   Don't average tank to tank-take an over all average. RIDE SAFE.

[Jess from VA]

What comes to mind is an episode of an old black and white sit com (maybe a 50's B movie).  The old next door neighbor is always going on and on about checking his mileage, and doing everything he can to increase it.  So the main characters start sneaking over at night and alternatively adding and removing gas from his car.  Predictably, the old guy about loses his mind trying to figure it out.

Any jokers at your house?  

That's all I got (except I seem to remember reading something about older plugs with widening gaps giving better mileage, though I may have that wrong)

You didn't switch to ethanol free did you?

[Itinifni]

All things equal, increasing your timing via the ECT mod should yield the best mileage.

Not sure about your drastic jump in mileage but agree with the others, right wrist control and keeping the rpm below 3k seems to result in the best fuel economy for me. But like others I didn't buy the beast for it's fuel economy.

For comparison, I average around 35 mpg in mixed driving but can vary it significantly based on my mood.

[Bone]

Anyone run across anything like this before?

pancho almost the same thing started happening to my 98CT last fall. It's not going as far as yours to reserve I get anxious and stop sooner. My last four stops have been 39 to 42 mpg average.

I haven't touched the carbs or ignition (except spark plugs)  in the bikes 145k miles history.
Last year I rode 11k miles to give you an idea of my use of the bike.

I think the reason for my bikes performance is the aging operator I'll be 70 years old this fall.
I'm just a little lighter on the throttle twisting 

[fudgie]

Could be your speed. I get 33 everyday. I once got 42 but was going 40 all day.

[The emperor has no clothes]

Anyone run across anything like this before?

pancho almost the same thing started happening to my 98CT last fall. It's not going as far as yours to reserve I get anxious and stop sooner. My last four stops have been 39 to 42 mpg average.

I haven't touched the carbs or ignition (except spark plugs)  in the bikes 145k miles history.
Last year I rode 11k miles to give you an idea of my use of the bike.

I think the reason for my bikes performance is the aging operator I'll be 70 years old this fall.
I'm just a little lighter on the throttle twisting 

Maybe at 145k it's now getting broke in. 

[Bone]

I'm avoiding touching the carbs I could ruin a good running engine

[Bagger John - #3785]

Tale of Two Valks.

Both have #38 pilot jets, pilot air screws 1 1/4 turns out from lightly seated. Dyno-Jet or Cobra adjustable jet needles (same overall taper), I/S carb springs, I/S ICM.

My '01 Interstate is stock in all other regards (intake, exhaust, Trigger Wheel) and gets 28-30MPG. It'll also wheelie in 5th if I play games with the throttle. The bike is making as much power as it can with OEM components.

My '99 Tourer (CA model) is also stock in all other regards (including smog plumbing and CA cams) and though it pulls a bit harder than it did before modification, its average mileage runs anywhere between 40-45 when ridden on the freeway at 70MPH. The bike has a Memphis Fats windshield and an I/S trunk attached, so there's a bit of drag which isn't present with a stock Tourer.

Interestingly enough, I did these same mods to my first two Valkyries ('00 I/S and '00 Tourer) and the results were the same WRT gas mileage and power.

[The emperor has no clothes]

Tale of Two Valks.

Both have #38 pilot jets, pilot air screws 1 1/4 turns out from lightly seated. Dyno-Jet or Cobra adjustable jet needles (same overall taper), I/S carb springs, I/S ICM.

My '01 Interstate is stock in all other regards (intake, exhaust, Trigger Wheel) and gets 28-30MPG. It'll also wheelie in 5th if I play games with the throttle. The bike is making as much power as it can with OEM components.

My '99 Tourer (CA model) is also stock in all other regards (including smog plumbing and CA cams) and though it pulls a bit harder than it did before modification, its average mileage runs anywhere between 40-45 when ridden on the freeway at 70MPH. The bike has a Memphis Fats windshield and an I/S trunk attached, so there's a bit of drag which isn't present with a stock Tourer.

Interestingly enough, I did these same mods to my first two Valkyries ('00 I/S and '00 Tourer) and the results were the same WRT gas mileage and power.

You can pull the wheel off the ground in 5th gear ?

[Houdini]

You can pull the wheel off the ground in 5th gear ?

Wheelies aren't so much power as skill.  I had a room mate years ago that could wheelie anything at any speed, and he made it look completely effortless.  He could ride wheelies off curbs, around corners, all kinds of crazy crap and he had his feel on the footpegs at all times.

I really hated that guy somedays....

[The emperor has no clothes]

You can pull the wheel off the ground in 5th gear ?

Wheelies aren't so much power as skill.  I had a room mate years ago that could wheelie anything at any speed, and he made it look completely effortless.  He could ride wheelies off curbs, around corners, all kinds of crazy crap and he had his feel on the footpegs at all times.

I really hated that guy somedays....

I used to be pretty good with dirt bikes. But I've only pulled the wheel off the ground in 1st gear on a Valkyrie. But I haven't really tried much.

[Jess from VA]

You get a 250lb back seater, wheelies become much easier.   

(I never want a back seater, esp a 250 lb one)

[Bagger John - #3785]

You can pull the wheel off the ground in 5th gear ?

Yep. Done twice, by accident. Both times at freeway speeds under moderate to hard acceleration; 4th-to-5th transition on my current I/S. To feel the front end get light was a little...disconcerting...while in traffic.

Once - I put down to the random alignment of the planets or other nonsense. Twice...indicates the correct state of engine tune.  

FWIW, the first I/S I had - which was tuned the same way - wouldn't wheelie as easily but it would unintentionally spin the back tire in 1st and 2nd on occasion during hard acceleration. By that, I don't mean abusive (dump the clutch and GO!) starts...just your run-of-the-mill freeway merges and getting up to speed on back roads from a stop. Ike (one of my coworkers, former Valk owner and Ohio VRCC member) witnessed this on a ride he put together, and subsequent conversations were always peppered with "....make MINE do that!".

[old2soon]

You can pull the wheel off the ground in 5th gear ?

Yep. Done twice, by accident. Both times at freeway speeds under moderate to hard acceleration; 4th-to-5th transition on my current I/S. To feel the front end get light was a little...disconcerting...while in traffic.

Once - I put down to the random alignment of the planets or other nonsense. Twice...indicates the correct state of engine tune.  

FWIW, the first I/S I had - which was tuned the same way - wouldn't wheelie as easily but it would unintentionally spin the back tire in 1st and 2nd on occasion during hard acceleration. By that, I don't mean abusive (dump the clutch and GO!) starts...just your run-of-the-mill freeway merges and getting up to speed on back roads from a stop. Ike (one of my coworkers, former Valk owner and Ohio VRCC member) witnessed this on a ride he put together, and subsequent conversations were always peppered with "....make MINE do that!".

              When that front end gits light yer heart Will speed up a tad. Simply Amazing How FAST old motocross skills got reawakened.  RIDE SAFE.

[Willow]

As to the original question there are two possibilities.

Not knowing how long the poster has owned the bike, it's possible that something that was partially clogged has finally been cleaned up.  That would account for improvement in fuel mileage.

It's also possible that the poster has changed habits in filling, either standing the bike up rather than on sidestand or simply filling further into the tube at the top of the tank.  That would explain further to reserve.

There is a third possibility if he's recently synched the carbs.  Done correctly that will improve fuel mileage. 

[pancho]

Well there is a lot of good thinking here,, a lot of it I have already done. While different filling habits will change the miles to reserve, it will not change the miles per gallon. Every tankful I divide the miles traveled by the gallons needed to fill up, (these days it is recorded to three digits) just to keep up on things. I have synced the carbs several times since I have had the bike, over four years, and always just under 32 MPG until the last four tanks.

I had thought something may have cleared or started working in one of the carbs Willow, been through them twice with no change, but I really think that something that would make such a drastic difference, 15 to 20 percent, would be noticeable in the motors operation, smoothness or less missing or something,,,  but I always thought it ran well and still does...??

I really like the 38 MPG,, maybe I'm just being blessed and need to leave it alone. I see that others mileage seems to be all over the board and it is attributed to riding habits,, what is an average mileage supposed to be according to the factory?

[Bone]

I'm a believer in non stop riding for better mileage. I have a Jeep Cherokee and running errands daily life stuff gets me 10 mpg. That is one thirsty 6 cyl.
I get out on the bike I leave town it's every block stop sign or light. Start and stop with all the gear changes is fun on the Valk but expensive at the pumps.

When I go for a ride I avoid towns even if it's several miles to ride around the city. As I've aged my throttle hand is much smoother. I realized going block to block I was opening the throttle (6 throttles) much more than needed you can still be quick but with a little less gas.

[pancho]

Whoa,, that is a thirsty Jeep Bone,,  my antique CHevy truck with an old school TBI 350 gets much better than that. I do agree that steady moving gives the best mileage,, but in my case, the riding habits or how I use the bike have not changed.  I just believing for it to stay the same or get even better!

[JimmyG]

I took a trip about a year ago and decided to try higher octane fuel. So I ran out the 87 and did a calculation on mileage and cost, then ran the highest I could find,93 octane I think it was. Calculated mileage and cost.  Cost of fuel per mile is was within a few tenths of a cent, while mileage and performance improved dramatically, in my opinion. By the way, I did this over several fill ups to wean out the blend.

[Bagger John - #3785]

I took a trip about a year ago and decided to try higher octane fuel. So I ran out the 87 and did a calculation on mileage and cost, then ran the highest I could find,93 octane I think it was. Calculated mileage and cost.  Cost of fuel per mile is was within a few tenths of a cent, while mileage and performance improved dramatically, in my opinion. By the way, I did this over several fill ups to wean out the blend.

Always run the lowest octane fuel that your engine will burn without pinging under heavy load.

93 octane isn't needed unless the compression ratio has been increased from stock (either through milling the heads or via forced aspiration) or unless you're doing something extreme with the timing.

Use of high-octane fuel is also somewhat counterproductive in a stock Valkyrie engine, as it's not all being burned. This can lead to cylinder washdown and accelerated ring wear.