my 1985 r80 was sitting for several years with gas in it. I rebuilt the carbs (bings) changed all fuel lines, filters, and plugs. It starts and idles fine once warm. It just doesn't have any power. I have never owned a airhead and this one was given to me. I have put 20 miles on it and it seems to me it is using a large amount of fuel maybe because I have to give it a ton of throttle to get it going. I have not changes the wires . Any suggestions what to try next.
I'll second the notion of obstructed intake. One of our IL members had a performance issue that turned out to be an oil soaked air filter from a mis-fitted breather tube. It ran exactly as you describe, start and idle just fine, no power when winding up the throttle.
former Airmarshal, IL.
Thank You. I did attend a Tech day and that is how the carbs got rebuilt. I had cleaned the tank and had it sealed. New petcocks, air filter, emissions removed, fuel filters, diaphragms, floats, o rings, valves adjusted.
Compression test? Obstructed exhaust? Pull the new plugs to look for lean or rich air/fuel mixture?, which is determined by coloration of the plugs, by the way.
former Airmarshal, IL.
While wires can contribute to poor running, in my experience this is not your issue. You can test this by touching the wires while the engine is running. This may sound crazy, but you'll be able to feel any leakage large enough to be an issue. And you'll be very sure of the results within seconds.
Far more probable causes are....
► Ignition timing. People think that just because they have electronic ignition that they never have to check this. Un-true. Borrow a strobe timing light and check the ignition at high RPM to align with the "F" mark on the flywheel.
► Lean carburation. This might be caused by the various conditions Scott alluded to.
a) Remove the fuel line from each petcock and turn it ON for a second with a cup under it. You should have a solid steady stream squirt out from each petcock at least 1 inches. If not, your screens are clogged.
b) While riding, see if ever so slightly turning the choke ON makes any difference. If the effect is positive, then that conclusively proves the engine is not getting enough fuel.
c) On the underside of the carb body, seemingly between the carb and intake hose, is a small cylindrical aluminum pipe about 3/8 long. That pipe either has to be 1) plugged with a metric screw, OR 2) must have a rubber hose on it connecting it to the same part on the other carb. If it has a hose, then the hose cannot have any cracks or holes in it. Those 2 ports must be plugged one way or the other.
Hope this helps.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
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