Gas Mileage

[Guest Rich Fernandez]

I have had modifications done to solve a vapor lock problem and apparently it has also increased my gas mileage. My early readings showed about 40 miles per gallon maximum for extended trips. Disappointed, I have not checked for awhile. Yesterday, I took a trip of some 200 miles. I awaited the dreaded light to appear around 130 to 140 mile range but to my surprise it never came on. This was running in cold temperatures out of Flagstaff, Az @ 7000 feet. Didn’t come on at 150 nor 160 and I began to think something is wrong with the light. I ran to 166 miles and decided that I needed to fuel just in case it was the light malfunctioning. It took 3.5 gallons. So about 47 miles per gallon with a little over 6000 miles on the odometer. I know that mileage should increase with break-in but have read several posts talking about getting used to low mileage. The modifications had to do with moving and insulating the fuel pump and opening the air box. I have also changed from stock to Quat-D pipes. In any case, the bike runs well and mileage has improved significantly. Don't know if others have experienced a similar increase. Any thoughts?

[Mike Stewart]

I usually could go 160 to 180 miles before the fuel light came on my 00 V11 Sport at freeway speeds. I have found that temperture really effects the mpg's of the Guzzi. The colder the temp, the lower the mpg. Carl and I found this out riding from California to Arizona for the Prescott Rally.

 

You may also be running lean with an exhaust change if you didn't remap with a Powercommander or such, which could get you a few more mpg.

 

Mike

[Guest AdamofKC]

Cold weather decreased your fuel consumption? On my bike, over the winter months, my mileage actually increased by a similar margin, but then my bike isn't a Guzzi. I though that at colder temps, the air would be denser and easier for the engine to make power, and didn't require as much fuel?

[Skeeve]

Cold weather decreased your fuel consumption?  On my bike, over the winter months, my mileage actually increased by a similar margin, but then my bike isn't a Guzzi.  I though that at colder temps, the air would be denser and easier for the engine to make power, and didn't require as much fuel?

83932[/snapback]

 

Your bike carbuerated? See my next post below...

[dlaing]

I used to have a Quat-D and it got about the same MPG while using a power commander that enriched it quite a bit.

If you have not enriched it, what Mike said may be the reason.

At 7000 feet you won't ping, but you really should have the bike mapped so that you don't burn a valve, or ping when you drop to lower altitudes.

Somewhere on the forum I posted a graph of my bike with the Quat-D before and after mapping and in some places it was something like an indicated 17:1 fuel ratio (way to lean). The power commander and the dyno tune made it run quite a bit better, but I still had a little ping in an area that the tuning link said to go leaner not richer. A few tweaks and it was much better.

FWIW I posted a while back that using lower octane fuel gave me better MPG, but I have not been able to replicate that experience and will chock it up to a tail wind. You should be very happy with 40MPG, as most of us get mid thirty MPGs

By the way, if anyone is curious, I ran out of gas today and it took exactly 5.0 gallons to fill it to the bottom of the fill neck.

As always, YMPGMV (your miles per gallon may vary)

[Skeeve]

I have had modifications done to solve a vapor lock problem and apparently it has also increased my gas mileage. ... Yesterday, I took a trip of some 200 miles. I awaited the dreaded light to appear around 130 to 140 mile range but to my surprise it never came on. This was running in cold temperatures out of Flagstaff, Az @ 7000 feet. ...I ran to 166 miles and decided that I needed to fuel just in case it was the light malfunctioning.  It took 3.5 gallons. So about 47 miles per gallon with a little over 6000 miles on the odometer. I know that mileage should increase with break-in but have read several posts talking about getting used to low mileage. The modifications had to do with moving and insulating the fuel pump and opening the air box. I have also changed from stock to Quat-D pipes. In any case, the bike runs well and mileage has improved significantly.  Don't know if others have experienced a similar increase. Any thoughts?

83929[/snapback]

 

Several thoughts, actually!

 

1) The "old ditch pump" as Pyotr the seasick sisal manipulator likes to call it is notoriously strangled as delivered from the factory, due to certification problems from such countries as Switzerland & the U.S.of A. The Quat-Ds are famed for beefing up the mid-range (just where we like to run'em when racking up highway miles); that extra power comes from decreased restriction & hence, increased efficiency.

 

2) The opened up airbox would decrease intake restrictions, & again, free up power that was spent dragging air into the chamber to be used to push you down the road. Increased efficiency when at steady throttle; every little bit adds up!

 

3) There is no 3.

 

4) You've discovered the big beauty of EFI: automagical correction for altitude! Up at 7000' ASL, you'd be running at a smaller jet size if on a carb'd. bike: less pressure means less air, less air means less oxygen, means you need less fuel for the same volume of air, means you get higher mileage [but less power], ceteris parabus, running at altitude. EFI makes this correction via the air pressure sensor, which then determines where the bike runs on the fuel map. Conversely, on a carb'd. bike tuned for sea level, you get worse mileage because it's running too rich [CV carbs are less susceptible to this, due to their design, but still need optimizing if constantly running at higher alt.s] and thus making less power, leading to greater wrist action, which in turn exacerbates the already too-rich running & leading to a decreasing spiral of trading fuel for power.

 

5) You gassed up at the top of the hill, & ran slightly downhill all the way on the rest of your trip, & then gassed up at the bottom to determine your mileage. You crafty devil!

 

Ride on,

 

[Guest trispeed]

After 2500 miles, I just got 40 MPG for the first time; I had been getting low to mid 30's, slowly increasing, as well.