The CB1100 Community Forum

Not sure this is mechanical/technical but I'll put it here anyway.

I bought my second 2013 standard a little over a year ago. It was in better shape than the first one but did normally idle high 1.9-2.1k or so. Occasionally it would come down for a bit but never really stay right. I thought it had to do with warming up or maybe outside temp. Basically I just dealt with it. It was really only bothersome at stop lights and pulling into the garage at night.

Suddenly things changed. About 6 weeks ago I got stuck in heavy stop-and-go traffic on 80 West in NJ heading to the Delaware Water Gap. It was pretty hot and I was on and off the clutch constantly. Pretty sore after a while. When I got out of the traffic and arrived at my meeting place, the idle was a nice low 900. Bike almost stalled in fact. I thought I had manifested another problem. Well to this day (no jinx), idle is perfect.

My half-brained theory: The woman I bought the bike from sold it because it was "too much for her." I think she was the second owner. It also came with loud yoshi exhaust. Some people like those I guess. I sold it and put the stock pipe back on. Maybe the first owner liked to hear the bike and revved it too much too often while at idle. Maybe the second owner wasn't a "perfect" rider and stalled too often from stops, so the bike "learned" her style and gave her extra gas when starting from a stop to help her not stall so much. Then after I had the bike for about 5k miles of absolute flawless riding, especially that trying day in traffic on 80, it learned that I don't need the extra gas to avoid stalling.

I'm pretty sure anthropomorphizing my CB doesn't provide the real answer. I'm just real happy to have a nice low idle back and super quiet bike.

That, or you have a faulty temperature sensor?

Normal spec. idle speed is 1100 +-100 rpm

On my '14 standard, high idle 1700-1800 began in June of '2016, or maybe it was '17?. For about 2 months it would happen nearly every day--I was riding about 5,6 days a week. Then it would be normal for a ride or two, then come back. Then one day the idle dropped to 500 rpm and the bike stalled in traffic. After, low idle at around 700 was intermitten for a few weeks. Then back to high idle. With cooler Nov temps it returned to normal (1100) for a about a week, at which time I traded it in. Seems like there were a couple of members at the time that reported that their bike did return to normal idle and stayed, but a number of folk eventually found IACV to be at fault, or ECM, which is dealt with in the long high/low idle thread...if you haven't had the pleasure:

[url=http://m.cb1100forum.com/forum/showthread.php?tid=8120&page=142]http://m.cb1100forum.com/forum/showthrea...0&page=142

Pretty well every time after a very long freeway run in the summer humidity and heat (i.e. off-ramping to pull over for refueling, bathroom break, water/coffee/food), the engine would want to stall due to extra low idling RPM. Typically I could recover it with some throttle therapy. I wrote this off as a hot lump and/or fueling system, regardless of the freeway speed air-cooling effect. Maybe it was not enough.

The other theory was the battery was overheated due to long exposure to engine heat from the constant freeway wind blast.

In any case, it was more of a nuisance and was manageable / learned to live with it. A cool down break usually resolved the behaviour.

I seem to recall having a similar experience on some other past inline-4 Honda and Yamahas, but never on twins or liquid-cooled bikes.

If it comes back, and you have $500 to spare, install a new ECU and enjoy riding the bike again.
Trust me.

(10-20-2023, 03:01 AM)Nachodaddy_imp Wrote: [ -> ]If it comes back, and you have $500 to spare, install a new ECU and enjoy riding the bike again.
Trust me.

I'm pretty positive to what nacho is saying. I do have a 2013 version with the A23 ecu installed and I'm having the same issue as you are (low idle and stalling)
Lift the gas tank and take a look at the ECU you might have the A23 version
So the solution to this is installing the new A24 version.
You can find it here :

https://www.partzilla.com/product/honda/38770-MGC-A24

I haven't order it yet as I'm still saving money for it

Expensive toys require expensive repairs

While you are saving your money, you can get the bike to run normally by putting it in "Limp Home" mode. This is done by disconnecting the throttle position sensor on the left side (as you sit on the bike) of the engine. The bike will run as it should except that engine revolutions per minute will be limited to 5,000, and the "check engine" light will be on. The other problems should go away in this mode.

That is still a very useable CB1100 limited to 5000.

I think mine has been to 5,000 rpms once in 73,000 miles. Mostly runs in the 2500-3500 range.