so it seems my bike has developed a problem...

Lately I have noticed 2 things with my bike.

1) After riding a while if I stop for something (gas for example), it is sits for a few minutes, it is very difficult to start again.

2) when I come to a light/stop sign, or whenever I stop, the idle comes down and idles at 2000 for a few seconds before finally dropping to ~1200rpm where it should be.

So my question is what would cause this on a 1982 XJ550?

What I have done

1) changed air cleaner (non-pod, stock-type K&N)
2) adjusted valve clearances
3) set idle mixture screw to 3 turns
4) adjusted float levels
5) synced carbs

Thanks in advance for the help.

 

Sounds like a good carb cleaning is in order. Correct me if I'm wrong but the idle issue could be the piston in your carb dropping down too slow. Stiction is the term I believe.

Very difficult to start again sounds like a fuel issue. Too rich maybe. I don't see colortune in your list.

 

The plugs are tan to gray. Not rich at all, and no I don't colortune.

Carbs were cleaned, but I guess I can always check the slides a.k.a. clunk test.

 

Now that the weather has warmed up I've noticed that mine is a bit harder to start after a short rest. I suspect that standing still like that the fuel in the bowls heats up - expands - and some gets up into the throat of the carbs flooding it a bit.

 

Check-out my "Filter Post"

It might be the gas!!!