Hunting rpm

[the Ferret]

Fingers crossed

[beardyweirdy@me.com_imp]

"Thank you for your feedback. I have seen posts in this forum where people claim a ECU change is available, and I have seen posts where people have been told by their dealer that a ECU change is not available. What year and model is your bike? Mike is a 2014 deluxe. Please post any news you have on tis subject. Thanks again."
"That's an interesting coincidence. The only time I have experienced the high idle / low idle - stalling is when riding around town, when I spend a lot of time waiting at stop lights. I thought maybe it was because the engine was getting hot, but the same thing has happened on a cool day (low 70's). Also, my wife is usually on the back when this happens."

Hi Dave,

Mine is a 2014 EX. Which is the same as your DLX I think. Twin pipes.

It seems that this is the only configuration that is effected.

I was planning a long trip, so steered clear of the new map at the last service. Plans have changed and I'll see if I can get it done this week. I totally know where your coming from. If I'm dawdling thru town in a pillion friendly low rev style, short shifting and being held up at long lights then it happens. Winter, summer what ever. I still think it could be the ECU putting a map in place when the oil temp reaches a certain point. Being air cooled if your not moving, your not really cooling much and even on a cool day you'll still warm up pretty quick in traffic. Total musing's here but if it richened up the fuling a touch in order to cool the engine, that could screw things up.. who knows. Like I say, utter guess work. I'll get it in to the dealers this week and let you know.

[Wisedrum]

My CB developed higher idle revs when being warmed up without me knowing why.
Since summer I get used to it and talked to Honda engineers about this phenomenon. One gave me the tip to ignore it and take it as being normal. There are a lot of sensors interplaying with the ECU, but which one can be the reason the higher revs? Another engineer suggested to let the ECU reset by a honda dealer and if this will not cause any change, then a new program can be played into the EPROM, which was developed to stop the low rev idle problem. It may help.

I will do the first and maybe the second step next spring. All I found out 'til now is, the engine has higher idle revs when it is cold, 1.500U/min. Then, when the machine is slightly warmed up, the idle speed sinks slowly down to 1.050. So far so normal.
After a few more km the idle speed does not return from higher revs when I close the throttle to these revs, but stays at 1.500 as being cold. But I can bring the engine to have the normal idle speed again by either use the key off mode and then start the engine again. Or I slow the machine down in a high gear, which causes less then 1.500. Then the idle speed is normal. I often use the second method. The CB is somehow a machine of mircales and wonders. And it is a standard 2013 one.

Wisedrum

[dave]

My CB developed higher idle revs when being warmed up without me knowing why.
Since summer I get used to it and talked to Honda engineers about this phenomenon. One gave me the tip to ignore it and take it as being normal. There are a lot of sensors interplaying with the ECU, but which one can be the reason the higher revs? Another engineer suggested to let the ECU reset by a honda dealer and if this will not cause any change, then a new program can be played into the EPROM, which was developed to stop the low rev idle problem. It may help.

I will do the first and maybe the second step next spring. All I found out 'til now is, the engine has higher idle revs when it is cold, 1.500U/min. Then, when the machine is slightly warmed up, the idle speed sinks slowly down to 1.050. So far so normal.
After a few more km the idle speed does not return from higher revs when I close the throttle to these revs, but stays at 1.500 as being cold. But I can bring the engine to have the normal idle speed again by either use the key off mode and then start the engine again. Or I slow the machine down in a high gear, which causes less then 1.500. Then the idle speed is normal. I often use the second method. The CB is somehow a machine of mircales and wonders. And it is a standard 2013 one.

Wisedrum

Once my bike enters the high idle (1,500 rpm) mode after reaching operating temperature there is nothing I can do, except unplug the EOT sensor, to get the idle back to the normal 1050 rpm. I have tried your suggestions and they didn't work for me.
Installed a new EOT sensor last Saturday. The idle speed actually returned to normal after warm-up (1,050 rpm) for a short while, but after a few miles of 2nd gear stop and go riding in the neighborhood it returned to 1,500 rpm (seems the engine just needed to get hotter). Unplugged the EOT sensor and the rpm returned to a perfect 1,050 (never ran better!). I was in a rush and didn't measure the resistance of either the old or new sensors before installing the new one. I checked the old sensor and it measured 1.90 kilo-ohm. I removed and inspected the new sensor and it measured 1.95 kilo-ohm. Both the old and the new sensors are out of spec, which is 2.4 - 2.9 kilo-ohm. Now I have to see if the dealer will swap this sensor for a replacement. Even though unplugging the EOT sensor causes the bike to run perfectly, and both of my sensors are out-of-spec, I am not convinced the EOT is the root cause. I sure hope Honda comes up with a fix because this is frustrating me, and I am out of warranty. I asked at the service counter if there were any known repairs for this condition and I was told that there are not any recalls or service bulletins available. So please, if anyone does get their ECM remapped by Honda then please let me know. I also tried disconnecting the battery to see if this would reset my ECM but this didn't do anything either.

[Wisedrum]

Seems we have the same problem.
I never disconnected the battery or the EOT sensor.

The engineer, who told me high idle revs can be normal, brought other argumentations into play. Maybe the lambda or the kat needs them to work properly.
He also thought the 1.050 would be too low anyway.
But that' s his opinion versus mine, who knows the lower revs were okay for nearly 30.000km. As a concluding idea he asked, how often let you run the Honda with idle revs on your ridings? Get the idea, so it should not bother you that much. But it does.

Sometimes the idle speed is okay by itself without me doing anyhing. But more often than I like it it is not.
As a general experience out of the last months I'm tempted to say, whenever the CB revs more than 1.500 it is not able to go beneath this mark again without a trick. And this it not normal to me, ' cause I know it was totally different from that.

Wisedrum

[kennyw]

Wisedrum, as an engineer, I don't think all engineers should give advice until they have spent time troubleshooting an issue. The guy telling you 1500 rpm idle is OK has not spent any time commuting on a motorcycle in heavy traffic.

[Wisedrum]

Strangely enough my CB don't need heavy traffic stop and go trips to fall into the high idle revs mood..10km of smooth riding is still enough for doing so.

But the engineers don't see my Honda , I only gave them a telephone call and they did the distance diagnostic advice without being too familiar with my problem, becaue they had never heard of it before.
And that is somehow familiar to me. One is always the first coming up with things others don't know.
But I'll try some things next spring and don't loose my faith in the Honda. Not now.

Wisedrum

[johnf514_imp]

Wisedrum, I had a a similar issue and recommend you get it looked at by certified techs as soon as possible. The high idle condition consumes more fuel, causes the engine to run hotter, and is dangerous as the high RPMs (mine were +2K when in gear) would pull me through corners rather than allow me to slow down in gear.

Honda needs to fix this for you as soon as possible.

[Ulvetanna_imp]

Wisedrum, I had a a similar issue and recommend you get it looked at by certified techs as soon as possible. The high idle condition consumes more fuel, causes the engine to run hotter, and is dangerous as the high RPMs (mine were +2K when in gear) would pull me through corners rather than allow me to slow down in gear.

Honda needs to fix this for you as soon as possible.

Yes.

[Wisedrum]

I fully understand what you mean.

But nevertheless me and my Honda can stand it for while. It's nearly winter, I'm not driving that much anymore and have still some other things on my work to do list than to bring the CB to a not nearby dealer, leave it there and in worth case spend a lot of money for a maybe open and aimless problem solution. All this while being out of warrenty for quite some time.

The high idle revs are no more than 1.500.
And as a kind of newly unorthodox behaviour I can bring the CB to rev sort of normal when idleing. As long as it don't pass the written number again. This of course is not the way things should be.

My W800, also using a fuel injection system, never has shown stuff like that wherever and how I have ridden it.

Wisedrum