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Yeah, I know - ANOTHER thread on fast idles. . .But following on from crazyriderguy's post in the sticky thread about holding the throttle closed while starting, I've done this a few times, and was wondering if it's a quirk of some Vulcans, or is it a feature? There's nothing in the manual about it.

The bike seems to idle and run fine, but I do wonder whether it's sufficient to get oil pressure up to spec before heading off?
 

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"Warm idle" should be sufficient for oil pressure; but it doesn't hurt to let the oil warmup on a cold day; which the fast idle helps with. The primary purpose of the fast idle is to prevent stalling when the engine is cold. Even with fuel injection, fuel doesn't aspirate well when it's cold and in a cold engine. So it doesn't burn quite as cleanly. Bumping the idle up a smidge keeps it running until it's warm enough to be the fine mist it needs to be. Essentially the same idea as the enrichener on carbed bikes (not to be confused with a choke which is an entirely different thing; but on most modern carbed bikes; they are referring to a choke which is actually an enrichment valve). Extra fuel helps counteract the sloppy fuel flow into the engine until things warm up. (Since fuel injected systems are under pressure, they are far less sensitive to these things. Which is why it 'works' even when you bypass fast idle.)

Personally, it doesn't bug me. My car does it too; it just isn't loud so it isn't as noticeable. When it's cold, I fire the bike up and take off when it comes down off of fast idle. When it's warm out, it doesn't always fast idle and even when it does, it stops by the end of the driveway.
 

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"Warm idle" should be sufficient for oil pressure; but it doesn't hurt to let the oil warmup on a cold day; which the fast idle helps with. The primary purpose of the fast idle is to prevent stalling when the engine is cold. Even with fuel injection, fuel doesn't aspirate well when it's cold and in a cold engine. So it doesn't burn quite as cleanly. Bumping the idle up a smidge keeps it running until it's warm enough to be the fine mist it needs to be. Essentially the same idea as the enrichener on carbed bikes (not to be confused with a choke which is an entirely different thing; but on most modern carbed bikes; they are referring to a choke which is actually an enrichment valve). Extra fuel helps counteract the sloppy fuel flow into the engine until things warm up. (Since fuel injected systems are under pressure, they are far less sensitive to these things. Which is why it 'works' even when you bypass fast idle.)

Personally, it doesn't bug me. My car does it too; it just isn't loud so it isn't as noticeable. When it's cold, I fire the bike up and take off when it comes down off of fast idle. When it's warm out, it doesn't always fast idle and even when it does, it stops by the end of the driveway.
I was just recently playing with one of those Coleman Gasoline camping cook stoves... Anyone who has lit one of those can understand exactly what happens when the fuel warms up and can be atomized easier. Don't flip that lever too soon! (If this doesn't ring any bells, then sorry for the distraction. If you have used one of those stoves though, it is a perfect illustration of the point. :) )
 
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