New guy needs help with fuel mileage

[Anonymous]

First, this site is a miracle for me, I've owned my allmost restored 80-81 GS850L for 7 years now and havnt been able to find competant help. I say 80-81 because it's an inbetween model year I think around October of 80 is the manufacter date but I'm not totaly certain of that.

Now for my question, I'm getting very poor fuel mileage, somewhere around 17-22 mi./gal. it was like this when I bought the bike used and since I've put over a thousnd into the engine it hasnt improved at all. All the work has been done by my local shop who said that was normal and that they couldnt anthing about it (now that I've spent alot of money on there sugestions). I had the engine rebuilt exept for the bottom, new coils, spark plugs, air filter and box plus hoses from box to engine. I'm at a loss, I love this bike but the fuel is killing me.

[Billy Ricks]

Have the carbs been gone through?

[chuckycheese]

Yep

I think Billy's got the answer. When I bought my bike, I used about half a tank of gas just to ride it home....about 35 miles!! I rebuilt the carbs and it runs just great. Also, I get about 45 MPG. Good luck!

[Anonymous]

I agree with your responders, Its most probably about carbs and less likely about timing which would be the actual timing and the automatic advancer. 17 to 20 is not at all normal. Read your plugs. use the Keith Krause method of driving at highway speed then cut the kill swich and pull in the clutch then read the plugs. Assuming the plugs are the correct ones, they will show signs of richness if it is the carbs. The ignition timing and automatic advancer can be diagnosed with a timing light.

[SqDancerLynn1]

Another possibilty is someone put the wrong carbs on the bike or rebuilt them with a generic kit.. I would go back and remove the carbs, clean them & check the jets making sure they are OEM jets Alot depends on your riding style If I run mine hard milage will drop down to the low 30's
real quick. The L model is always a problem because it has such a small tank

[chuckycheese]

YES

That's a great point! I failed to mention in my previous post, when I rebuilt the carbs, they did contain generic jets and a couple were the wrong size!

If you don't know which sizes you need, you'll get plenty of help on the forum.