05-17-2022, 10:05 AM
Alright guys. So I've been dealing with this issue since last summer, when I started noticing sitting in traffic, the revs would drop low to around 600-800 rpm. I ride year round in the Triad area in NC. During the mild to cold weather, the revs would remain high, and maybe for a golden 5 minutes after starting the bike up at work to make the 20 mile commute home, it would act normal. However, all other times, it has pretty much all of the symptoms of the IACV issue. Let me list them just so we're on the same page.
- Normal idle rpm in neutral
- Shift into gear - crack open the throttle, hangs out at around 1500+ rpm until it decides to maybe drop down to 1100-1200rpm.
- Clutch in at a stop in 1st gear, normal-ish idle. Release the clutch only slightly, revs start to ramp up 2k+ as the clutch is released.
- Clutch fully released, revs drop to around 1600 rpm, still uncomfortable in some low speed situations. I need to use more rear brake for the low speed maneuvers than I should have to, as the bike is ramping up the revs without my input.
- Highway, slowing down from approx. 60-70 mph, let off throttle, rev match to downshift a gear, release clutch properly, *clunk clunk clunk* as the bike bucks and tries whatever it is doing. This does not happen 100% of the time, but I can feel the rev hang (engine braking is NOT consistent) while letting off the throttle in gear. Feels like a super lazy cruise control. Letting off throttle barely slows me down in the higher gears.
SO I think that's it as far as symptoms. I'm prone to forgetting some things, but I think that's pretty accurate. I've experienced all the issues.
I went ahead and went on eBay and bought a used '12-'16 CBR1000RR throttle body for $60 with a factory IACV, because I am a cheap b*sterd. I just finished up the IACV swap this last weekend, put everything back together, and after 95 miles of commuting, the idle issue is STILL existent.
I have not looked into if the CBR1000RRs had idle issues like ours, but I was hoping that the idle issue was only isolated to the relatively smaller batch of bikes that is the CB1100. Although I swapped it with a used part, I find it unlikely that I'd have the exact same issues as before, unless there was a deeper issue, such as the ECU.
I really love this bike and I plan on keeping it until it's completely roasted, but this issue is really killing my affection for it.
I really would like to have a good known ECU in hand so I can rule out that it might be an ECU issue. If anyone has one I can rent or borrow for troubleshooting, that would be fantastic.
Of course, any other suggestions other than buying a brand new IACV, and still having the same issues, would be welcomed as well.
Cheers
- Normal idle rpm in neutral
- Shift into gear - crack open the throttle, hangs out at around 1500+ rpm until it decides to maybe drop down to 1100-1200rpm.
- Clutch in at a stop in 1st gear, normal-ish idle. Release the clutch only slightly, revs start to ramp up 2k+ as the clutch is released.
- Clutch fully released, revs drop to around 1600 rpm, still uncomfortable in some low speed situations. I need to use more rear brake for the low speed maneuvers than I should have to, as the bike is ramping up the revs without my input.
- Highway, slowing down from approx. 60-70 mph, let off throttle, rev match to downshift a gear, release clutch properly, *clunk clunk clunk* as the bike bucks and tries whatever it is doing. This does not happen 100% of the time, but I can feel the rev hang (engine braking is NOT consistent) while letting off the throttle in gear. Feels like a super lazy cruise control. Letting off throttle barely slows me down in the higher gears.
SO I think that's it as far as symptoms. I'm prone to forgetting some things, but I think that's pretty accurate. I've experienced all the issues.
I went ahead and went on eBay and bought a used '12-'16 CBR1000RR throttle body for $60 with a factory IACV, because I am a cheap b*sterd. I just finished up the IACV swap this last weekend, put everything back together, and after 95 miles of commuting, the idle issue is STILL existent.
I have not looked into if the CBR1000RRs had idle issues like ours, but I was hoping that the idle issue was only isolated to the relatively smaller batch of bikes that is the CB1100. Although I swapped it with a used part, I find it unlikely that I'd have the exact same issues as before, unless there was a deeper issue, such as the ECU.
I really love this bike and I plan on keeping it until it's completely roasted, but this issue is really killing my affection for it.
I really would like to have a good known ECU in hand so I can rule out that it might be an ECU issue. If anyone has one I can rent or borrow for troubleshooting, that would be fantastic.
Of course, any other suggestions other than buying a brand new IACV, and still having the same issues, would be welcomed as well.
Cheers