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mpg?
- Thread starter rickieh
- Start date
Here's a post by PamcoPete http://www.xs650.com/forum/showpost.php?p=147517&postcount=14
He did some nice research with his ignition system. As for modded bike, I'd think you could get better millage by shaving off pounds by eliminating or getting light components. Of course that is offset the how heavy the rider is. Bored out bikes will do worse on mpgs.
Looking at the MPGs in Pete's post, he's a master when it comes to tuning.
He did some nice research with his ignition system. As for modded bike, I'd think you could get better millage by shaving off pounds by eliminating or getting light components. Of course that is offset the how heavy the rider is. Bored out bikes will do worse on mpgs.
Looking at the MPGs in Pete's post, he's a master when it comes to tuning.
pamcopete
Ride.Enjoy.Life is Simple
Well, I don't know about that. Keep in mind that the test runs I did were with the intention of comparing spark plugs and coils so each run was as close to identical as possible, including.
1. 95% uncongested highway, not the Interstate.
2. Steady 55 MPH.
3. Good atmospheric conditions, IE high barometric pressure, moderate temperature.
4. Tires pumped to 32 PSI.
5. Windshield. There is some controversy about whether a windshield helps or hurts gas mileage. I'm of the opinion that it helps because it presents a more regular shape to the wind.
6. 87 Octane gas. I think that you get better mileage from 87 Octane that you do from 93 Octane because it burns faster and more completely than 93 Octane in the XS650 engine.
7. Exact same 70 mile round trip route for each run.
8. Filled up at the same pump before and after each run.
9. Very few traffic lights and slowed down for any red lights to avoid stopping when possible...
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Goldy
XS650 Enthusiast
Running points ignition, std bore, std carbs, std gearing. Mikes XS air filters and mufflers. Has returned a constant 65mpg since I got it in '79 ...keep in mind that's an Imperial gallon, not a US gallon.
pamcopete
Ride.Enjoy.Life is Simple
OK. So, 65 MPG (Imperial) is = to 54 MPG (USG)
(I thought they used liters uip in Nova Scotia, not gallons.)
I've been getting about 150mi per Texas gallon.
But, at a steady speed on level ground, say 55, miles covered is always the same f(x) crank rotations. So the only thing that could affect the mpg is mix, with leaner giving higher mpg. If there's any shifting happening, then other factors come into play.
But, at a steady speed on level ground, say 55, miles covered is always the same f(x) crank rotations. So the only thing that could affect the mpg is mix, with leaner giving higher mpg. If there's any shifting happening, then other factors come into play.
I do very poorly with the tiny little Japanese Gallons.
Yes it's a joke there used be a saying about some of the Japanese horsepower ratings. "Well yes it makes 100 HP but they are tiny little Japanese horses".
Yes it's a joke there used be a saying about some of the Japanese horsepower ratings. "Well yes it makes 100 HP but they are tiny little Japanese horses".
CDNTX650
XS650 Guru
We have never really fully switched to metric...
im 28, i have no idea what you would weigh in kilos, but i know how heavy you would be in LB's....same with inches, i use inches for everything when i measure, but lots of heights for switches and stuff are given to me in cm's. They just switched the Canadian Electrical code book to metric like 3 years ago, no more 1/2, 3/4 conduit in it etc, in mm now....sigh..
Goldy
XS650 Enthusiast
Yep, the road signs and measures up here are metric, but my brain still works on the old Imperial system.
When my Daddy and I used to go to Canada every week he would always insist on filling the tanks in the US because he didn't understand that Imperial Gallons were bigger and I was never able to convince him otherwise.
I sure do miss that stubborn old man.
I sure do miss that stubborn old man.
Here is what I got last summer on a 2080 km trip in the mountains of British Columbia. Lots of up hill/down hill riding of course, and thinner air at the higher elevations.
23.7 km/L , 4.2 L/100km, 55.8 mpg (US gallon).
23.7 km/L , 4.2 L/100km, 55.8 mpg (US gallon).
I was getting 57 mpg with stock mains (132.5). Last Sunday I swapped them for 135's and it really smoothed out the motor and gained a bit of power. We'll see what happends with the mileage.
Marvelicious
Naturally Aggravated
About the only long-term benefit I got from buying and selling drugs in my younger days was a solid working knowledge of weight conversions from metric to US standard. I started by learning that there are approximately 3.5 grams per 1/8 oz, and by the time I got out of that world I was familiar with the 2.2 lbs per kilo conversion. I learned liquid volume by brewing beer and small distances by turning wrenches. Funny how a person picks things up.
Tomterrific
XS650 Junkie
My '77D is stock with straight through mufflers and K&N pods. Stock 17-34 gearing. The pilot and main jet are 0ne size larger, the needle is lifted one notch. I did a series of mileage checks and the mileage hovered around 50mpg, varity of conditions. Bike runs well, very smooth, good power and rpm.
A more powerful ignition coupled with wider plug gap and taller gearing (lower rpm at speed) should have better mileage. Perhaps dramatic.
Tom
A more powerful ignition coupled with wider plug gap and taller gearing (lower rpm at speed) should have better mileage. Perhaps dramatic.
Tom
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I found the '76-'77 carb set I have returns slightly better mileage (about 52) compared to the original '78 set (about 50). This probably has to do with the difference in main jet sizes (132.5 vs. 140).
Tom, running your needle one step richer than stock is probably hurting your mileage. You might see an improvement by increasing the main more and setting the needle back at stock or even one step leaner.
Tom, running your needle one step richer than stock is probably hurting your mileage. You might see an improvement by increasing the main more and setting the needle back at stock or even one step leaner.
