fuel mileage

[canman80]

Checked my mileage today,84 miles on 3.5 gallons of fuel.Around 24mpg.Is that normal???Last 2 tanks of fuel have been 93 octane,she seems to run better on that..does having a fairing hurt or improve mileage??just wonderin.........

[Ken Talbot]

When I filled up Tsunami last night, it took 4.31 Imperial gallons, total distance 192.9 miles. I had just had to switch to reserve, and we always use regular gas. This works out to 44.8 mpg (Imperial), or 35.8 mpg (US). This tankful was all highway miles, and that's with a Vetter fairing, tall windshield, saddle bags, and trunk. SWMBO's 'H, with the same travel distance, riding speed, and equipment package worked out to 45.4 mpg (36.2 mpg US), but she is usually closer to 50 mpg ( 40 mpg US). Must be time for a tune up on her bike...

[TopCatGr58]

Hey there Canman,

Like Ken said, depends on other circumstances as well, ie. the speed that you did those 84miles, like over 70-80mph, will eat it up faster. Or, was it a lot of stop and go traffic, again, not as efficient as steady speed driving. How's the condition of your air filter(s), clogged and cause it to suck up more gas than air!?

I like to play with the throttle, but on my last LDR alone, with loaded soft side saddlebags and backpack on seat, small chest windscreen, running 1179 Big Bore kit in 81SH, 117.5 mains, Indy filters, 4-1 pipes, I only got about 32MPG on 93 Octane ! Also your compression, condition of your rings, spark plugs, timing, etc. can play into it as well. But I would think that 26mpg is a bit low!? YMMV!

T.C.

[beechfront]

i've seen that

my mileage varies considerably. anywhere from 28 to 40.

28 when I'm really messing around a lot, 40s on open highway 70mph and under.

Depends mostly on my driving, but wind/weather also play a big part.

I'm running a 79 special.

[Mike Hart]

I just did a 2300 mile trip on my XJ loaded down w/ fairing and (as always) too much baggage.

Over the whole trip I averaged 33.75mpg. A lot of the time was on jets that were still too rich (127.5 mains, 50 pilots).

Over the course of the trip I wound up at 125mains and 47.5 pilots. For the ~900 miles in that config, I avg'd 34.33mpg.

Big difference between under 70 and over 70! I got from 38.6 to 40.77mpg on sections of road where I couldn't exceed 65-70, while on interstate or other places where I could go over 70 (and usually did, sometimes cruising at 80 with short stretches of over 80 I avg'd about 32-33mpg.

When my bike was stock except for small Nat'l Cycle windscreen, I consistently got 40mpg on <70 runs, somewhere around 30-33 on crazy runs.

I've been to enough rallies to know for sure that an XS11 should get in the very high 30's, 37-40mpg if you keep it under 70.

Anything consistently less than ~32mpg indicates

• you are a maniac
• your jetting has been modified to the rich side
• there is something wrong

[graybird78]

gas mileage

large canman - i have an '80 sg full dress & i get about 33 to 36 miles to the gallon unless i play with the throttle. then i still get about 31 to 33 miles to the gallon. seems to me that you may have other problems as far as your gas mileage goes. sound like you may have carb problems running too rich. your bike should be able to get at least 30 mpg. but that is just a guess on my part - not sure how you ride your bike. the worst gas mileage i have ever gotten with my bike is 30 mpg. but i was riding my bike pretty hard when i got that mileage. i would look at spark plugs & air filter to see if i had any kind of restrictions for air & plugs would be black & sooty if you're running rich. best of luck - keep us posted. and we'll see if we can help.

Graybird78
'80 SG

[graybird78]

OOPS!!!

SORRY FOR CALLING YOU LARGE!!! FORGOT TO TAKE OFF "LARGE" FOR WORD SIZE....

[Pat Kelly]

When I first used my colortune I found that the carbs transition from pilot jets to main jets around 4200 RPM (appox. 70 MPH in 5th gear).
I determined this because I had one cylinder that had spark but no fuel until 4200 RPM. I moved the suspect pilot jet to another carb and the symptom followed (that explained why it felt like a turbo kicking in when it went from 3 to 4 cylinders).

[canman80]

Forgot to mention that most of my driving is mostly stop and go around town mostly...haven't had her on any big rides yet...

[MartyA]

Well I can't relate to "stop and go around town" since my town has only a couple of stop signs and one new traffic light. On a dice run yesterday, mostly 55-60 with a few stops and a few throttle blips, I squeezed in 3 gallons after 125 miles, which is 40mpg using regular grade juice. On superslab trips where I am at 70-75 ish, I consistently get 34-35 mpg. I have a Vetter, 4-1 Mac, 4 indy filters, bigger jets.

I suppose if you were "in town" and participating in a stoplight derby for a good part of the ride, I suppose your mileage could drop below 30 mpg.

[jiminos]

on my SH i get around 42 to 45 if i keep it under 60.... as i approach (or go over) 70, mileage drops to around 35... running stock carbs with dyno jet stage 3 kit, K&N indies and 92 octane.