idle speed question

[AprilIan]

I rode a couple hundred miles today and ran into something I've never encountered before.

My idle speed would stick at 2500-3300 all day long when the bike was in gear, but the moment I shifted into neutral, the RPM dropped to 1500. If I then shifted back into gear, the RPM's stayed down. If I shifted N to 1 and let out the clutch for a couple of seconds then the RPM would stay at the higher level. The temps were 28-42 F.

At first I thought, perhaps the clutch was not disengaging completely until I realized the speed would drop in gear, not go up. Has anyone seen anything like this? What do people suggest I do for diagnosing what is going on here?

it is a stock '03 with the map previous to the '05. all else appears to be fine.

[mnrstrider]

Are you sure this is not a sticky throttle cable? I know mine sticks a bit, look back a page or two you'll find a "current" thread discussion sticky cables, and lubing them. I can't tell from your post so well exactly what you are trying to say. Mine will stick a bit say if I pull up to a stop sign, with my clutch in, if I just let it out a bit when I'm stopped or moving slow it drops right down. Wash your bike recently? Mine really likes to stick the next time I ride after I wash the bike. I highly doubt this is an tuning issue, although some people swear it is...

[AprilIan]

Nope Nick, sticking cable is not it.

Clutch pulled to the bar in any gear (moving or stopped) - revs sit around 3k. If I don't change throttle or clutch - just move to N the revs drop to 1.5K. put in any gear - remains at 1.5k, but let out clutch and move forward then pull clutch in again and it's back at 3k.

Does that help clarify?

[AprilIan]

Nick turned me on to the concept of it being a stepper motor issue. I read som posts he pointed out. looks like I'll open the airbox if it hasn't magically dissapeared as some posts reported.

thanks Nick!

[mnrstrider]

While you're in there you can easily remove any excess plastic

[AprilIan]

hey Nick (MNSTRIDER) aren't you supposed to be working?

[mnrstrider]

[AprilIan]

OK

so this morning it was 38 degrees and the bike did not exhibit the same problems.

the problems happened yesterday when the temperature was 28 degrees. Revisiting the problem, I now realize there was a stall when cold too. Each time I resarted the bike (4 times) that day the problem was there. the problem was even present when I started the bike at an ambient air temp higher than this morning's 38.

everything else is exactly the same.

I think I'll keep an eye on it and until it is reproducable, until then I'll just call it "character"

[Badger]

There was a thread about this a while back, started by Vic_&_Will maybe? My bike did something similar although it never idled as high at 2500-3300. When in gear, the bike would idle around 1200, and when neutral around 1500-1600, but otherwise exactly as you described. Somebody in the original thread narrowed it down to being an electrical issue. Anyway, as soon as I did the wiring modification, this went away. Coincidence? Possibly. But now the bike idles rock solid around 1200-1300 regardless of gear or neutral.

[bossbob]

There was a thread about this a while back,

ONE? only one?
You are quite right, there have been threads on this issue, several over the last couple of years but can I remember the outcome? NO

I was thinking about it today and seem to recall one of them was the oil drain tube from the airbox was full and had allowed oil into the stepper motor.
Another, was indeed electrical, low voltage confusing the sensors
And in the early days I think we associated it with the TPS (throttle position sensor) being on some kind of borderline
And right back at the begining, I told Podpeeze it was because he was molly coddling the bike, and to cane it's sorry ass up and down the motorway to cure it D
It didn't fix anything, but he at least enjoyed himself

Oil in air box, stepper motor, low voltage or TPS.... take your pick

[rblue02]

Didn't you leave out

"Not allowing enough time for the ignition-on-sequence before starting."


and how about
"Don't crank the throttle whilst starting the bike".

[Befbever]

We've not heard of RobC either who had a high idle and was going to fix it with Tuneboy.

[RobC]

that was about 1500rpm regardless of the clutch/gear situation. Yes, reloading the map and zeroing sorted that. I have had the high tickover when in gear once or twice - switching off for 30 secs then on, letting the startup sequence complete before starting the engine sorted that. In my case I'm convinced it was through being too hasty to get the engine turning.
Ps Damp cold roads + 9 points on my license has raised mpg from 32 to 36! Now if I could just get the hang of this 'speed limit' theory.....