I have an 08 roadglide that did this all day yesterday. It had happened before around the 370 mile mark,rolled back the throttle and made sue the EITMS was off. Even tried it on but idle still at 2000. It did it the whole ride home and all the way to work this morning. (some stop and go and hwy riding both ways) idle at stops was 2000.
This same issue has been mentioned by others on various hd forums. Some say harley knows of problem and is working on a fix.Others ahave been told by there service department it will fix itself.
I 'm calling my dealer today to see what they have heard.

Thanks in advance for all the great advice i hope to recieve
08FLTR
Black
no mods

 

I'm told there is a procedure to reset it in the factory service manual which says turn the ignition on then off 4 times waiting 10 sec in between. Good luck.

 

How about we try and keep the original posters problem as the main topic here,
not what others have had on other year bikes.
The 08's are a little different being they are first year to have ETC (electronic throttle control)
Now barring an out and out problem with any component or a bad design to start with,
a high idle of 1 minute or so upon a cold start, or a hot restart is not necessarily a problem
or a defect.
when it does it while riding, or is prolonged for several minutes may be.
Now on older models and this is just BASIC info so bear that in mind.
fuel injected. does not have a manual choke (enrichener control).
so during a cold start the ECM "senses" everything is cold (air, fuel, motor)
and does an ELECTRONIC cold start (like you pulling the choke on a carb)
But since it doesn't have an actual choke plate it accomplishes it in other ways.
It (ECM)adjusts the throttle opening by way of the IAC (which by the way is more or less
sealed unit so external lube really doesn't do much good).Unless you remove OBVIOUS
gunk around the opening that can impede the pintles movement in and out.
It (ECM)controls how much fuel is sprayed by the injectors (when you pulled the choke
you basically cut down the air flow to the motor, thus causing the carb let engine run rich, by having the same amount of fuel but less air) then you normally would hold the throttle a little
more open until engine started to run more smoothly.
Ecm is doing the same thing Electronically.
As engine warms up, it decreases the fuel flow to injectors, adjusts the throttle plate opening via the IAC, and starts reading the signals from the head temp sensor, map, air intake temp
sensor, and any other applicable sensors on your particular bike.
In any internal combustion gasoline engine, you control RPMS by controlling the air going into
the engine via the throttle not the amount of fuel! electronic fuel injection is no different.
After any above engine has been operated long enough to be thoroughly warmed up (even hot you might say) when you turn it off it immediately goes into "heat sink" mode.
As it is cooling off externally, some of the fuel and intake components are actually absorbing
more heat. this lasts for approximately 30 minutes to an hour depending on the conditions
occurring at that time.
so when you first do a hot restart, the ecm is still receiving "I'm hot signals" from the different
sensors. and sometimes it may indicate excessive heat, so it will make adjustments to try to
cool itself down, sometimes this means adding fuel and throttle to raise RPMS.
But when all things stabilize and the across board readings are more accurate, it will then
idle back down. this is provided every component is working as it should.
and anything manmade wears out eventually (god made our bodies and we wear out)

08's are no different except now the throttle plates themselves are controlled by the ECM.
In the above scenario the throttle plates were still cable controlled.
The throttle control in the 08's apparently have bit getting used too.
They have a zero point setting, and apparently a below zero point capability also, based on his saying he could turn throttle grip more towards closed and it would idle down.
This could be normal or not. If normal, you are overriding the computers control past
it's "known and calibrated" zero idle point. forcing it to recalibrate your new position.
But it could be a matter of adjustment. will have to get a trustworthy dealer (that's an
oxymoron id I ever saw one) to honestly admit to you what is happening.
a lot of you appear to be "shadetree" mechanics. You've learned by doing, and watching and asking questions. But apparently few or none have actually been to school and learned the
basics on up (heat sinking, rpms control, how a choke and ECM system actually does it's job
behind the scenes). for exa

 

Just returned from a trip where the fast idle was a problem to and from the destination, with a gas stop on the return. Idle was between 1500 to 2300 at stop lights the whole way. Tried this reset a few minutes after getting home while the bike was still hot and it worked! Went for a short ride and restared the bike seveal times and it immedietly settled to 1000 rpm idle each time. Thanks for the tip! 2008 FLHTP