CB1100 Idle speed instability problem

[Nachodaddy]

In my case, with the 2013 standard, replacing the iacv was a $700 waste of time. I read how difficult it was and decided to have it done at a shop. I paid the money and left with high hopes of a good running bike. It went right back to the problem very quickly. Only when I replaced the ECU did the problem completely and permanently disappear. I did the ECU replacement myself and it was quick and easy. I ordered the replacement from Partzilla and it had a different part number than the original, but it looked the same. That was for a 2013 standard. I don't know about other years or if other years have the problem. I wish the best of luck to anyone with this problem. 

[Cormanus]

Replacing the ECU seems to me consistent with the European experience of having the problem fixed by Honda upgrading the software (re-flashing the ECU). What doesn't make sense to me is Honda America denying there was a problem that could be fixed easily with a quick re-flash. Did Honda Japan not tell them, or did they not want to hear? Or is it something else again?

[Nachodaddy]

Cormanus, I agree and it was not only Europe that knew about this. One of our (old) Forum members from South Korea wrote that he had the problem and his local Honda shop replaced the ECU and fixed it. After reading that, I decided it was worth a try. I can only think the problem lies with Honda (Motorcycles) US.