Quick question: Idle speed at start-up

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prshguy

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In about 10 minutes I'm going to check out on 05 FJR. In one of the pics sent to me the guy has just started the bike and the tach is showing 2000 rpm. Is this normal?

 
Ambient temp was probably about 50 so I guess it's nothing to fret about. Thanks for the quick reply.

 
Is this normal?
If you ask me, NO !

I would suspect the idle adjuster is set to high.

Even in cold, and I get cold temps here, initial startup RPM is maybe 1400.

At warm idle the FJR engine should be at ~ 1000.

 
When the ambient temperature is low, the ECU runs the engine a little fast. Once the temp starts to riase, the idle speed kicks down.

 
Mine idles at around 2k on cold starts... But it comes down to about 1100 as soon as 1 bar appears.

 
Mine cold idles (on start up) at 2k rpms regardless of ambient temps. If it's hot outside, then it's quicker to drop down to 1100 (set by the idle adjuster knob on the right side down below the tank).

 
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+3

In addition, the ECM only varies the fuel mixture, fast idle is controlled by a wax pellet style coolant heated thermostat located under the TB's (hence the variable rpm range), along with a Rube Goldberg arrangement of linkages that operate a plunger air bleed setup not unlike Mikuni Carb cold start valves. Cold idle is adjustable there, but since the whole assembly is beneath the TB's entirely, it's not something that can be done easily.

 
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regardless of what people's bikes do (mine has varied depending on which mechanic does the servicing) I would recommend you have a throttle sync and adjustment done if you buy it. That should get it to factory specs if performed properly.

 
+4

It does not matter what the ambient temperature it, it will always start at about 2000 when the engine is cold. Once it warms up, it should drop to 1000 rpm. If ambient is hot, then it should not take long for it to drop. It takes a little longer during cold days (about 1 to 2 minutes tops)

 
-1 to this ----> It does not matter what the ambient temperature it, it will always start at about 2000 when the engine is cold.

If the ambient is about 75 mine starts at about 1500 rpms and below that temp it starts at 2000 rpms.

 
Oh shucks, my motorcycle ran just fine until I read this thread :blink: When the weather is warmer I get lower startup RPM, usually around 1.4k RPM and when it is colder it can go as high as 2k RPM. Guess I'm going to have to troubleshoot and repair this tragic malfunction some time in July when the temps get over 70 degrees here in NH. Just think, my bike has been AFU all this time and I never even noticed ;)

 
+5

Started mine a few days ago when it was about 35 degrees. Noticed the idle seemed a little higher than usual. Just over 2K but it quickly returned to regular idle speed after a couple minutes. Took it for a short ride- all was good in the world. Mine anyway.

 
Well gents, the bike was very nice and it liked me so much that it followed me home :rolleyes: so I guess I'll have to keep it. Just finshed tucking it in for the night, can't wait for the weather to cooperate.

Thanks for the all input, didn't expect such a great response. Sounds like the high idle is about normal although when I sync the TBs I'll see if I can't bring it down. Since I'm new to this site, has someone posted instructions on TB syncing?

 
Congrats on becoming a Daddy! Now go fix your sig line. ;) See ya on a future group ride w/ the Norcal Clan!!!

 
Oh shucks, my motorcycle ran just fine until I read this thread :blink: When the weather is warmer I get lower startup RPM, usually around 1.4k RPM and when it is colder it can go as high as 2k RPM. Guess I'm going to have to troubleshoot and repair this tragic malfunction some time in July when the temps get over 70 degrees here in NH. Just think, my bike has been AFU all this time and I never even noticed ;)
+1

 
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