900SS high idling in stop-n-go traffic

[printman]

Also the reason the idle seems to jump so high over the 1200, as you stated 3XXX, is because of the ignition system.

The ignition modules are set up to advance to full advance (around 32 deg BTDC) at a low 1500 rpm's.

This causes the engine to accelerate when under no load to the 2800 - 3000 range. Under load it can be controlled better, but doesn't like it that low.

[♣ McKraut ♣]

Yes.  You either want it to idle right when it's cold (it won't stay cold) or you want it to idle right when it's hot (it will get hot).

Why does it matter whether you have to use the choke or not when it's hot?  Remember, it's not actually a choke; it's another carburetor.  But, actually, I think you'll be surprised.  When cold, choke it and thumb the starter, but don't mess with the throttle.  It'll start right up, idle at 1200 for a few seconds, then head for 3000.  From there, lower the choke till it's idling about right, then take off.  The idle will clean up usually within 3 blocks, and you can turn the choke lever completely off.  I just click it off while riding.  When it's still hot from a ride (say an hour maybe) then just hit the starter; again, don't use the throttle.  When it's setup right, it's generally harder to start if you insist on trying to use the throttle while cranking.  There's no accelerator pump, so there's no real point in it, anyway.

sounds good man...i just wanted to feel comfortable that i was treating the bike properly.  it always starts right up with high idle; never a problem there.  so i'll just continue to do that and screw with (literally) the idle to set it for a bit lower than it is now.  thanks again.

[♣ McKraut ♣]

after going for a couple more rides and thinking about this further, i'm not sure i agree with this solution of adjusting the idle down further.  my reasoning is that the idle seems to be fine (albeit on the low side), it's just that there is an unintentional "high idle" when the motor hits higher temps (130C+).  i can still force it back to the normal 1200ish RPM idle; i just have to put it in gear, and let the clutch out a bit to bog the motor down...and then it just "finds" the correct idle again.  so adjusting the idle would not really be a "solution" to the problem, in my mind.  there is something else at work here that needs to be addressed, i'm just not sure what it is.

[Hedgehog]

Did you richen up the idle mixture yet?  If not ...

[sur4die]

you need to sync your carbs.

http://www.ducatisuite.com/carbsynch.html
this link gives you the general idea. 

you don't need fancy gauges though, just get some clear vinyl tubing that fits the emissions nipples (i think it's 5/8" ).  you'll need about 12'.  take the middle of the tube and secure it to the bottom of a yard stick, secure (with tape or wire) the tube up both sides of the stick and fill the tube with water so that it comes up the stick about half way.  i then drape your new "differential manometer" over the handlebars and connect the ends to the emissions nipples.  kink the tubes with a vice grips/clamp, and start the bike.  let it warm up then remove the clamps.  if the water doesn't stay level then you need to adjust the synch screw (hiding above the idle speed screw) until they are reasonably level.

to adjust the sync screw you normally need to loosen the oil cooler to get it out of the way.  it's kinda hard to reach otherwise.

it's really not that hard, and once you have done it the first time it's really easy to do it again....  kinda like makin'  .


edit: oh, and the reason this happens is that your carbs are essentially fighting against each other.  one cylinder/carb is trying to operate at one speed/opening and the other at a different speed/opening.  when it's cold the slower carb is winning.  once it gets warm, the faster carb is winning. 

[♣ McKraut ♣]

you need to sync your carbs.

thanks for the info man...i appreciate it     SUPER DUKE! (aka RichD of the "PugglePod" fame) here in the DFW area with an SS (and a 1098) agrees with you about the syncing.  i'd like to give it a go myself; hopefully in the coming week or two i can give this a try.

thanks again!