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Interesting. Sometimes restarting a computer solves a problem but other times a "cold boot" is necessary. Have you tried disconnecting the battery for 15 minutes or so then reconnecting? Disconnecting the battery should clear any corrupted code or fragmented memory from the ECM computer(s) and force a reload of a "clean OS" from permanent storage.
If this "cold boot" doesn't work, then the weak battery theory is probably a good one.
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(12-31-2016, 09:52 PM)curlyjoe_imp Wrote: Interesting. Sometimes restarting a computer solves a problem but other times a "cold boot" is necessary. Have you tried disconnecting the battery for 15 minutes or so then reconnecting? Disconnecting the battery should clear any corrupted code or fragmented memory from the ECM computer(s) and force a reload of a "clean OS" from permanent storage.
If this "cold boot" doesn't work, then the weak battery theory is probably a good one.
Update:
My bike was idling at 2200 rpm in gear and 1600 in neutral after trying to start w/ a very weak battery (it sat for 3 weeks or so and battery over 3 years old). Idling did slightly improve when fully warmed up but still funky.
So, I disconnected battery, squeezed brake lever (to discharge any remaining juice in capacitors), charged the same battery, drained the air box vapor collector (somebody here said to do so can help this idle issue; its the short, plugged 90 degree tube in front of air box; it was full of brown liquid that dribbled out), connected battery, turned on ignition, did the throttle roll-on procedure w/ key on before starting, turned key off, turned key on, then started the bike.
Runs as normal, 1400 rpm cold idle (it always did that), go for a ride and it idled at 1050 rpm when warmed up in a couple minutes or a mile or 2. Things seem to be back to normal for several rides now.
Try these home remedies if your bike is idling erratic and post results. Maybe this is the re-boot procedure for a confused ECU w/ a weak battery issue and air box condensation issue.
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What would be the point in replacing the IACV with an original Honda part? Wouldn't the new one crap out like the one from the factory? Has Honda corrected the issues and there are new IACVs available?
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Today I experimemted a bit with the tips of 736cc. After performing all the steps in his instruction, the CB did not stayed on its higher idle rev anymore on the 90km long trip.
Whenever I released the throttle, it found its way back to 1050 rev for idleing, as Honda has originally intended and programmed it. So, for now the problem seems to be solved.
Time will tell for how long. I hope forever, 'cause it's been quite a while since the CB had the low idle rev. In the last half year there was no ride, in which the Honda seems not to be fixed at 1.500 for idleing. And I'm still searching for an answer, why it has been so.
Wisedrum
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So Wisedrum, which tips did you experiment with or was it all of them?
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As I wrote, I worked on all the tips/steps in the described order. The only thing I left out, was to charge the battery. In my opinion it was strong enough and didn't make a weak impression.
Today follows a second testride, to find out, if something has changed back
to the unnormal idleing. Hopefully not.
Wisedrum
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Wishing you good luck, Wisedrum. Mine is still idling great since track day at Laguna Seca in mid-November.
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Thank you, Rolls!
Sometimefeels it feels, as we live in a land full of mircales and wonders.
Maybe the CB is part of it. May this kind of Honda voodo has cured its disease.
Wisedrum
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736cc...with your permission (hopefully) and credit given, I have reposted your proceedure in the How To section of the forum. Hopefully others will give it a try and give us some more feedback.
http://www.cb1100forum.com/forum/showthr...?tid=10073
Thanks, Ferret
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I read through this entire thread and believe the rpm increase during warm up is normal, especially during cool temperatures. The ECU will rev up engine when cold to reach a specified catalytic converter temperature during open loop. Once temperature is reached, the lambda sensor will signal to the ECU to go into closed loop ( normal idle rpm). If you are near the threshold for closed loop and ride off, the catalytic converter will cool off enough to go back into open loop. I have seen this happen on several vehicles, especially on cold mornings. A motorcycle has its catalytic converter exposed to air cooling.
