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Earlier this winter ("southern" NY state..brrrr) I synched the throttle bodies. Upon doing this, I noted that the idle speed seemed to run faster upon a cold (20 F/-7 C) start than I was used to hearing: right at startup, the rpm jumps to 2500, then grows to perhaps 2750 (never hits 3000), then slowly decays back to normal, just under 1000 for me. The rate of this decay and the time to first temperature bar appearing seem fine. This scenario actually represents my second iteration at throttle body synching. In my first attempt, I unwittingly moved to air screw/idle knob combined settings that did not allow the slow idle to be set below ~1100. After checking the fora, I learned of the subtle interaction of the air screws and idle knob, and in my second adjustment have moved to a combined setting that allows the slow idle to be set all the way down to about 750, even though, of course, I have it set to about 900-1000. The cold start fast idle behavior seemed pretty much unchanged between these two synching trials, however.

It is possible that my memory is fading (fast!), and that this cold start fast idle behavior is just fine. But it seems changed to me, too fast... So I ask: for others who start and use their FJRs in the cold (mine is my daily commuter, unless snow/ice is present or threatened), what fast idle behavior do you see?

Secondly, what else can I check? I have measured the resistance of the throttle position sensor and it is in spec. Other ideas? Other things to adjust?

Thanks!
...damocles
 

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If you are setting the thottle bodies to approx. 250mm at 1000rpm... then I'm not sure how this could affect idle. I have only done this once... last weekend, so it's still fresh in my mind. My bike usually sits in a heated garage so I don't routinely start the engine in colder weather. I have noticed idle speeds as high as 2500rpm on a few colder days when I left work. The return to normal idle speed does seem to correspond to just after the first bar on the temp graph. It all sounds pretty normal.

Take care
 
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