Erratic idle speed

[lather]

Since I performed my valve adjustment and throttlebody sync a few months ago my idle has been somewhat erratic. Most prominently, on cold weather, cold engine starts the fast idle seems rough and warmup takes longer than before. Occasionally the fast idle is faster, sometimes the fast idle does not seem to come on at. Also, after the engine is fully warm the idle will occasionally be to low and I will need to adjust it up. Then later in the ride it will be too high. As I said, this is erratic and does not occur every ride, just occasionally and with no clear correlation with ambient temp.

Since all of my EX valves have been way tight on both my adjustments I set them near the loose limit this last time, maybe that is a factor. But I am also thinking I did not do the TB sync quite right, although the sync results were excellent and idle is much smoother than before the sync, (other than when the fast idle is on).

Anybody have any  ideas?

[Gearhead82]

My idle seems a little funky to me too.  I'll start it up when it's cold and it will idle smoothly at what seems like a normal "fast idle" RPM.  Then by the time I get to the first stop light about a mile down the road, the bike will be idling slower than normal at about 900 RPM.  Then by the next time I stop a couple minutes later, my idle is at the normal ~1150 RPM and it will stay there until the next time it's cold.  I noticed it after removing the flies, but the bike only had a couple hundred miles on it when I pulled them so it could have been doing it since it was new.  I've always wondered if the ECU switches to the "normal" idle sooner than it should before the engine is all the way up to temp or something.

[B.D.F.]

Mine does this too. It seems to be because the engine comes off 'fast idle' before it is really fully warmed up so the initial idle (the initial normal idle) is a bit low and when the engine reaches full operating temp., the idle speed comes up to its final and correct speed. There really is no fix for that without getting into the ECU and re-coding how fast the fast- idle circuit ends, which is entirely impractical of course.

What I have done with mine is to raise the mechanical idle speed a bit and it has worked out well for me. I used to have my bike idle on the low side, 1,000 to 1,050 RPM but it would be well under 1,000 RPM when at that in-between condition. I now set the idle to about 1,200 RPM and even the lowest idle speed is fast enough. Overall, I find the bike just a tad easier to ride in stop- and- go city riding too with the idle set a bit higher- it is easier to launch, especially two-up.

Brian

Since I performed my valve adjustment and throttlebody sync a few months ago my idle has been somewhat erratic. Most prominently, on cold weather, cold engine starts the fast idle seems rough and warmup takes longer than before. Occasionally the fast idle is faster, sometimes the fast idle does not seem to come on at. Also, after the engine is fully warm the idle will occasionally be to low and I will need to adjust it up. Then later in the ride it will be too high. As I said, this is erratic and does not occur every ride, just occasionally and with no clear correlation with ambient temp.

Since all of my EX valves have been way tight on both my adjustments I set them near the loose limit this last time, maybe that is a factor. But I am also thinking I did not do the TB sync quite right, although the sync results were excellent and idle is much smoother than before the sync, (other than when the fast idle is on).

Anybody have any  ideas?

[stevewfl]

I think you all should insure your FOB bats are fully charged, allowing KiPass to AX the problem

[lather]

Thanks for the reply, encouraging to hear mine is not the only one.  I had my idle set at 1300 before my TB sync due to rough idle. Now that the idle is very smooth I tried going back to 1100 but that did not work  due to the "fast idle" issue. I now have it set at 1250 and it seems to be working well. I agree it does work better for slow speed launches.

Mine does this too. It seems to be because the engine comes off 'fast idle' before it is really fully warmed up so the initial idle (the initial normal idle) is a bit low and when the engine reaches full operating temp., the idle speed comes up to its final and correct speed. There really is no fix for that without getting into the ECU and re-coding how fast the fast- idle circuit ends, which is entirely impractical of course.

What I have done with mine is to raise the mechanical idle speed a bit and it has worked out well for me. I used to have my bike idle on the low side, 1,000 to 1,050 RPM but it would be well under 1,000 RPM when at that in-between condition. I now set the idle to about 1,200 RPM and even the lowest idle speed is fast enough. Overall, I find the bike just a tad easier to ride in stop- and- go city riding too with the idle set a bit higher- it is easier to launch, especially two-up.

Brian

[reesedp]

I think you all should insure your FOB bats are fully charged, allowing KiPass to AX the problem

Steve, I just wanted to tell you how much I've enjoyed the KIPASS quips since the new site came up.  I tried to throw a few out but I think you just have the market cornered...

[Conrad]

Steve, I just wanted to tell you how much I've enjoyed the KIPASS quips since the new site came up.  I tried to throw a few out but I think you just have the market cornered...