MPG and modifications poll

[olebiker]

Originally posted by corey
79 Special, Jardine pipes, EMCO pod filters, rejetted... its been so long I don't even remember the jet sizes!!! Either way, I get about 32-34 MPG. Close but no cigar!!


I should note that my mileage went up since I fixed my gas filler seal. Evaporation is a mother, ya know?

How did you fix it? I didn't know you could buy a seal (mine leaks).

[Derwat]

Stock 79SF, aftermarket mufflers (not performance)

36mpg at sea level, 32-34mpg normally (imperial gallon)

[corey]

The new seal came from MikesXS. I don't remember the part number, but if you do a search for "gas tank seal" and my name it should come up, and fairly recently too.

The avatar: its a picture from the single "Stinkfist" by Tool. Enough said.

[Dennyz]

Since I have re-thought my jetting setup for fuel economy, I am now getting 38-39mpg. AND, no noticeable loss of power. Maybe I can only go 120mph now, instead of 125. I can live with that (literally). My driving style has not change. I like to go fast and hit the corners hard.

My 'F' has a 4:1, can muffler, K&N filter with a drilled out air box, 140.0 main jets, 45.0 pilots and 135 miles on the odometer.

The intake and exhaust mods cause a low RPM lean out. By running larger pilots to address this, the XS motor retains its low end power. Up above 2500 RPM, at cruising speed, the motor does not need that kind of richness.

This is further supported by the number of owners that are running custom exhaust and intake on stock jetting. And are completely satisfied with their performance.

I started with 145.0 mains and 45.0 pilots. The bike ran strong, but only got around 35mpg. I reduced the mains to 142.2s and the pilots back to 42.5s. I lost the low end power I like and my fuel economy did not improve. I put the 45.0 pilots back in and the low end power returned. Fuel economy showed no noticeable improvement. Reducing the mains to 140.0s brought my fuel economy up to 38-39mpg. I new I was on the right track.

I am ready to return my mains to 137.5 (stock) and leave the pilots at 45.0. But, I just did the XS850 F/D conversion and want to test my mileage before I make any more changes.

My recommendation is to bump the pilots up and leave the main stock.

[egleaves]

Dennyz, I like your approach to the jet size conundrum. I haven't gone so far as to change my jets yet, but when I do I am going to remember this post and re-jet accordingly.

A little trial and error is likely to only way to find the perfect jet size since everybody differs in their bike configuration and/or riding preference.

[pete_s]

Milage Mods

Running two up with a Vetter fairing on a XS11 I am getting 45 to 46 MPG with varied riding.

Stock intake and exhast I believe are helping allong with XS11 final drive from Ebay for $36.

Carb jetting is all stock and the needle is centered and suggest the the low mpg bikes may have the needles raised (e clip lowered on the needle) and will cause it to run rich(fat) with carbon on the plugs and exhaust.

The Needle and Needle jet control all fuel flow from off idle to full throttle when the main kicks in, limits the flow Syncronizing the carbs may be another thing to be carefull with and will affect MPG. I spend some extra time doing it

Connecticut has 10% ethanol so I didn't think I could get 45MPG but my numbers don't lie

[Paintman]

MPG

Stock engine stock ex good tuneup with full vetter Fairing and bags with 750 Mod i turned out an avg of 42.3 mpg i am very happy.


John

[Gyrogearloose]

Good mileage.

Last week on a trip to Winthrop, Wa. from Coupeville, Wa. I got 43 -44 mpg. That's a 360 mile trip. My 80' SG performed well amongst the Harleys and Wings'. The only mod I know of is a 4-1 exaust. Stock intake and jetting. I'm scared to touch it for the needed cam chain replacement. Ha.

[Pat Kelly]

It's sad when my son's car (1993 Ford Escort) gets better MPG than my bike. Drove the car to OR and got 37 MPG on the way there (70 - 75 MPH). On the way back kept the speed to 60 - 65 MPH and got 43 MPG.

[Crazcnuk]

I doubt his escort is getting more than your bike, according to your numbers.

I drove a '96 Escort for 10 years and it averaged 36-38mpg on Imperial gallons.

And I did everything I could to get better mileage out of it, as I put 212,000kms on it in that time.

[Pat Kelly]

My bike(s) get 34 MPG. Escort wins this time .
I still prefer the bike.
Now my Volvo gets from 6.5 to 8 MPG. I once got a bit over 10 but then picked-up 42,000 lbs of wine and the avg dropped to 7MPG.

[olebiker]

Originally posted by Pat Kelly
My bike(s) get 34 MPG. Escort wins this time .
I still prefer the bike.
Now my Volvo gets from 6.5 to 8 MPG. I once got a bit over 10 but then picked-up 42,000 lbs of wine and the avg dropped to 7MPG.

Pat that sounds like a very large party

[snowdog51]

the steez

so mikuni makes a pump that works with trottle when you twist the trottle it gives a squirt so jetting can be lean just like a car with a carb . i'm going to look in to this see if it can be had it could help with trottle
response.
bill

[xschop]

Anybody else trying Acetone?

1oz. per 5 gal. I just started a tank and will post results. The bike starts up alot easier I noticed right off the bat and she's got more pep....stay tuned

[nezzer]

Completely stock '80 Special. I get 39 miles to the gallon. The bike is incapable of getting anything but 39 mpg. I drive lower speeds through the country, high speed highway, standstill rush hour.... doesnt matter. I still get 39 mpg. Sometimes I even drive like a a-hole just trying to see if I can make it budge off 39. No luck so far.