imported post
negold wrote:
81 GW GL1100 STD
Does anyone have an idea of the mileage I should get.
This bike has 145 main jets is this correct.
Is 4800 rpm for 65mph normal
The bike has plenty of power and getting 30 mpg but idles rough has 37k
ordered new timming belts and plugwires alreadyreplaced plugs rebuilt carbs and balanced also ajusted valves
Negold, I can't tell you what main jets you are supposed to have but even if you find the original build spec they could have been changed as well as the needles that ride in them due to Honda's running changes or to cure a power problem..
In any case your main jets aren't your mileage problem as they have very little effect on common operation fuel economy. If you ride at 3/4 (or more) throttle position for normal riding they will then start to effect your economy. For most NORMAL riding your fuel side economy is derived from; first pilot jet needle setting as you are riding on the pilot jets mostly at low throttle opening, next followed by the slide needle's large diameter shank size and or needle jet size. Needle position in the slidecan also have an effect in the transfer area but I believe those needles have a fixed position in the slides.
Running with your choke on can really show in your fuel mileage,, lugging that free revving engine can also lower fuel mileage,, large windshields can have a pronounced effect at hi-way speeds,, riding at over 65 MPH can also lower your mileage substantially.
Places to look if nothing obvious found-
Look for higher than spec carb float levels..
Look for unbalanced carbs..
Look for plugged, partially plugged, or lazy air cut-off system (this is a real biggy as far as poor mileage goes)..
Look for a plugging air cleaner..
Look for low voltage to the ign coils (it happens).
Look for dragging front or rear brakes (quite common on older bikes)..
Check the ign timing & spark advance as a late spark, or lazy vacuum advance can play havoc with your MPG.. (lazy advance is somewhat common to find on those early bikes)..
Make sure the fuel you use is without alcohol.. (high alcohol content in the fuel for older bikes really changes the fuel mileage)..
Twisty