CB1100 Idle speed instability problem

[Cormanus]

G'day Anders and welcome to the forum. Thanks for adding to our store of information on this issue. Your English is excellent and we'd like to hear more from you about your bike and your experiences with it. We once had another member in Denmark, but he's not signed in for a while.

 

[AndersL_imp]

G'day Anders and welcome to the forum. Thanks for adding to our store of information on this issue. Your English is excellent and we'd like to hear more from you about your bike and your experiences with it. We once had another member in Denmark, but he's not signed in for a while.

Thanks Cormanus, this is a great forum with tons of information. This bike is very seldom seen in Denmark (only a handful I guess) because it was never sold by Honda in Denmark. Mine is a demo imported from Germany.

 

[GoldOxide_imp]

Welcome to the Forum Anders. Glad to learn your idle problem was resolved. Great warranty - extended warranty? Don't get that as standard in Canada. When not elsewhere, you will be here.

 

[zirconxi_imp]

Bikes at 33500km mileage, rode for 6 hours under hot weather last Saturday, while returning home the bike suddenly gone into high idling while waiting at traffic lights to turn into my housing area. 1st time it happen. Stop engine and restart doesn't solve it. unplug and plug back EOT then she return to normal (I had my finger burned trying to do this).

Trying to find the cause online and end up reading 61 pages in this tread for the past 3 days (not giving up yet, will continue again). From what I have read, it seems like this problems can be from multiple fault, but all giving same symptom. hence some method works while some don't. Anyway, i updated the spreadsheet with my details (I deleted some lines which are empty without any data. i double triple check and its all empty row. hope i didn't delete the wrong thing.). hoping others can find their solutions.

My friend's CB have the idling too slow and engine stalled problem as well before this, but he solved his by spraying something into throttle body, to clean it he say...

 

[pdedse]

Bikes at 33500km mileage, rode for 6 hours under hot weather last Saturday, while returning home the bike suddenly gone into high idling while waiting at traffic lights to turn into my housing area. 1st time it happen. Stop engine and restart doesn't solve it. unplug and plug back EOT then she return to normal (I had my finger burned trying to do this).

Trying to find the cause online and end up reading 61 pages in this tread for the past 3 days (not giving up yet, will continue again). From what I have read, it seems like this problems can be from multiple fault, but all giving same symptom. hence some method works while some don't. Anyway, i updated the spreadsheet with my details (I deleted some lines which are empty without any data. i double triple check and its all empty row. hope i didn't delete the wrong thing.). hoping others can find their solutions.

My friend's CB have the idling too slow and engine stalled problem as well before this, but he solved his by spraying something into throttle body, to clean it he say...

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.

 

[Riko_imp]

Bikes at 33500km mileage, rode for 6 hours under hot weather last Saturday, while returning home the bike suddenly gone into high idling while waiting at traffic lights to turn into my housing area. 1st time it happen. Stop engine and restart doesn't solve it. unplug and plug back EOT then she return to normal (I had my finger burned trying to do this).

Trying to find the cause online and end up reading 61 pages in this tread for the past 3 days (not giving up yet, will continue again). From what I have read, it seems like this problems can be from multiple fault, but all giving same symptom. hence some method works while some don't. Anyway, i updated the spreadsheet with my details (I deleted some lines which are empty without any data. i double triple check and its all empty row. hope i didn't delete the wrong thing.). hoping others can find their solutions.

My friend's CB have the idling too slow and engine stalled problem as well before this, but he solved his by spraying something into throttle body, to clean it he say...

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.
did I miss something? but there isn't a fix, still remains a mystery what the cause is, let alone what the solution is

My low idling stalling was not fixed, but resolved by replacing the whole throttle body under warranty luckily.
Thats no fix, thats guessing and hoping for the best, and it worked out.

I doubt the IACV is the cause and the solution for the idling issues.

As of today, Honda has not recognized it as a big enough issue to organize a recall on particular models of the CB1100.

 

[zirconxi_imp]

Bikes at 33500km mileage, rode for 6 hours under hot weather last Saturday, while returning home the bike suddenly gone into high idling while waiting at traffic lights to turn into my housing area. 1st time it happen. Stop engine and restart doesn't solve it. unplug and plug back EOT then she return to normal (I had my finger burned trying to do this).

Trying to find the cause online and end up reading 61 pages in this tread for the past 3 days (not giving up yet, will continue again). From what I have read, it seems like this problems can be from multiple fault, but all giving same symptom. hence some method works while some don't. Anyway, i updated the spreadsheet with my details (I deleted some lines which are empty without any data. i double triple check and its all empty row. hope i didn't delete the wrong thing.). hoping others can find their solutions.

My friend's CB have the idling too slow and engine stalled problem as well before this, but he solved his by spraying something into throttle body, to clean it he say...

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.
did I miss something? but there isn't a fix, still remains a mystery what the cause is, let alone what the solution is

My low idling stalling was not fixed, but resolved by replacing the whole throttle body under warranty luckily.
Thats no fix, thats guessing and hoping for the best, and it worked out.

I doubt the IACV is the cause and the solution for the idling issues.

As of today, Honda has not recognized it as a big enough issue to organize a recall on particular models of the CB1100.

I think there are multiple causes thus multiple solutions. All these are different problems but will show the same symptom. Some are electronics/electrical (Sensors, contacts, wiring, battery), some software (corrupt data, firmware corrupt, error in program), some hardware (IACV, Throttle body, dirt, sticky pin, electrical motor, vacuum leak), some mixture of a few, some other unknown. I think Honda wouldn't issue a recall if there is not a specific design fault that cause the same problem.

 

[Riko_imp]

Bikes at 33500km mileage, rode for 6 hours under hot weather last Saturday, while returning home the bike suddenly gone into high idling while waiting at traffic lights to turn into my housing area. 1st time it happen. Stop engine and restart doesn't solve it. unplug and plug back EOT then she return to normal (I had my finger burned trying to do this).

Trying to find the cause online and end up reading 61 pages in this tread for the past 3 days (not giving up yet, will continue again). From what I have read, it seems like this problems can be from multiple fault, but all giving same symptom. hence some method works while some don't. Anyway, i updated the spreadsheet with my details (I deleted some lines which are empty without any data. i double triple check and its all empty row. hope i didn't delete the wrong thing.). hoping others can find their solutions.

My friend's CB have the idling too slow and engine stalled problem as well before this, but he solved his by spraying something into throttle body, to clean it he say...

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.
did I miss something? but there isn't a fix, still remains a mystery what the cause is, let alone what the solution is

My low idling stalling was not fixed, but resolved by replacing the whole throttle body under warranty luckily.
Thats no fix, thats guessing and hoping for the best, and it worked out.

I doubt the IACV is the cause and the solution for the idling issues.

As of today, Honda has not recognized it as a big enough issue to organize a recall on particular models of the CB1100.

I think there are multiple causes thus multiple solutions. All these are different problems but will show the same symptom. Some are electronics/electrical (Sensors, contacts, wiring, battery), some software (corrupt data, firmware corrupt, error in program), some hardware (IACV, Throttle body, dirt, sticky pin, electrical motor, vacuum leak), some mixture of a few, some other unknown. I think Honda wouldn't issue a recall if there is not a specific design fault that cause the same problem.

One thing is know for sure, nobody knows anything really.

Again, all speculation from our side.

 

[GoldOxide_imp]

Had an Aprilia that would sometimes unexpectedly slip into low rough running or rough idle. The root cause of a wiring harness connector above the engine that would experience impaired connectivity. I suspect it has something to do with vibration and/or expansion from engine heat. Nevertheless, compressing the connector (and re-seating each conductor) and holding it tightly with a tie-wrap stopped the problem.

- - -

Mentioned many times throughout the Forum, however, wiring/connector issues owns a lion's share of rider pains.

 

[pdedse]

Bikes at 33500km mileage, rode for 6 hours under hot weather last Saturday, while returning home the bike suddenly gone into high idling while waiting at traffic lights to turn into my housing area. 1st time it happen. Stop engine and restart doesn't solve it. unplug and plug back EOT then she return to normal (I had my finger burned trying to do this).

Trying to find the cause online and end up reading 61 pages in this tread for the past 3 days (not giving up yet, will continue again). From what I have read, it seems like this problems can be from multiple fault, but all giving same symptom. hence some method works while some don't. Anyway, i updated the spreadsheet with my details (I deleted some lines which are empty without any data. i double triple check and its all empty row. hope i didn't delete the wrong thing.). hoping others can find their solutions.

My friend's CB have the idling too slow and engine stalled problem as well before this, but he solved his by spraying something into throttle body, to clean it he say...

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.

zirconxi, as one who had high/low idle issue, sorry to hear your bike is acting up.

I think it was SportsterDoc who came up with a trouble-shooting list of where to start from simple to more complex possible causes--I searched but couldn't find it. Dave in San Diego outlines the more complex fix--the IACV.
did I miss something? but there isn't a fix, still remains a mystery what the cause is, let alone what the solution is

My low idling stalling was not fixed, but resolved by replacing the whole throttle body under warranty luckily.
Thats no fix, thats guessing and hoping for the best, and it worked out.

I doubt the IACV is the cause and the solution for the idling issues.

As of today, Honda has not recognized it as a big enough issue to organize a recall on particular models of the CB1100.

I think there are multiple causes thus multiple solutions. All these are different problems but will show the same symptom. Some are electronics/electrical (Sensors, contacts, wiring, battery), some software (corrupt data, firmware corrupt, error in program), some hardware (IACV, Throttle body, dirt, sticky pin, electrical motor, vacuum leak), some mixture of a few, some other unknown. I think Honda wouldn't issue a recall if there is not a specific design fault that cause the same problem.

One thing is know for sure, nobody knows anything really.

Again, all speculation from our side.

I think your statement "nobody knows anything" goes too far. Perhaps we're not sure why the IACV failed for several owners, but it does seem to be a main "suspect". Dave reported in this thread how and why he replaced the IACV. Problem did not return. I forget the name of another owner who had his replaced under warranty, problem did not return. Your throttle body was replaced--which the IACV is part of (I think, correct me here if I'm mistaken) and the problem didn't return for you (or did it? IIRC, you sold the bike).

Some have reported doing things other than IACV replacement and the problem did not return, while others have tried the same things that "worked" for some...only to find that such fixes didn't work. I myself tried several things with no apparent luck; but after cleaning the TPI connections the bike was free of high/low issues for a number of weeks at which time I traded-in the bike. Was it fixed? I don't know...that was during winter and maybe the colder temps dampened the problem.

Again, correct me if I'm mistaken, but I remember reading in the forums that the part number for the IACV for years 2014 and prior is different than part number for IACV for '17EX models. The different part number might mean that Honda DOES know something and they did a fix--hence, new part number...but they aren't telling us.

 

[pdedse]

I found the post from SportsterDoc that I was looking for. It gives one a starting point:

Summary, to date:

Regarding popgun's post 619, referencing "BBS" issues on the Honda Rune Forum: Further research indicates that BBS is black exhaust smoke and fouled spark plugs from running too rich, which that forum has attributed to a TPS issue.

Suggestions if you experience low/high idle issues:

1. Check for active codes, per page 5-12 & 5-13 of the Factory Service Manual, checking the codes lists on pages 5-15 & 5-16

2. Check for stored codes, per pages 5-14 of the FSM

3. If no codes, then insure that there is no vacuum leak. An unlit propane torch applying propane to intake areas, engine at idle, will detect a leak by listening for a change in idle speed. Check vacuum hoses and fittings, one 4 way (17201-MCJ-003, $7) and one 5 way (17201-MCZ-003, $5.60), then snug all 8 clamps from throttle bodies to intake.

A. Disconnect Throttle Position Sensor connector (engine OFF), clean contacts (contact cleaner available at Home Depot or Lowes, etc.), check for damaged wiring and reconnect. GO FOR A RIDE. If issue persists, continue

B. Disconnect Idle Air Control Valve, clean contacts, check for damaged wiring and reconnect. GO FOR A RIDE. If issue persists, continue

C. Follow TPS diagnostics per pages 5-23 thru 5-25 of the FSM. Note comments in posts 615, 618 & 622, especially see Max's post 632 regarding TPS output test. If output is not 0.5 VDC, loosen fasteners (ignition on, engine NOT running) and rotate TPS to obtain 0.5 VDC, throttle closed. After adjusting TPS throttle closed output, do a throttle calibration with ignition on, engine NOT running, by SLOWLY opening and closing throttle, 2-3 times. GO FOR A RIDE. If issue persists, continue

D. Follow IACV diagnostics per pages 5-74 & 5-75 of the FSM. If OK, then remove IACV, clean IACV port and check for unobstructed travel. If not OK, IACV (16430-MJF-D01) is $119.13 from Honda. GO FOR A RIDE. If issue persists, continue

E. Follow EOT (Engine Oil Temperature Sensor) diagnostics per 5-21 of FSM, particularly resistance value of 2.4 to 2.9 Kohms (2,400 to 2,900 ohms) at 20C / 68 F. If not OK, EOT sensor (37750-KPH-701) is $34.56 from Honda. GO FOR A RIDE. If issue persists, re-check the FSM diagnostics. Note that a faulty ECM is a possibility, albeit rare. The only time I recall a failed ECM on a Sportster, was due to an internal 5 VDC sensor power supply failure.

The EOT (Engine Oil Temperature) sensor and IACV (idle Air Control Valve) are available from Honda. The Honda Rune Forum has posted a TPS replacement for the Keihin JT6H TPS: 16060-MBZ-A11, $114.29 from honda. This is for a 2006 CB600F. The Rune Forum posted that this sensor is a Keihin JT6H, but we have not yet verified compatibility

For non-USA owners, check that the latest ECM program is installed by your dealer.

 

[SportsterDoc]

From reviewing recent posts on this thread and the Curley Joe Spreadsheet, I am inclined to conclude that most issues are IACV and/or ECM program related, with the exception of a damaged TPS wire and maybe one EOT.

The problem with my suggestion D was not knowing the effort and complexity required to remove the IACV until Dave did so.

Those replacing the entire throttle body assembly, including Riko, replaced the IACV, which "resolved" his issue.

Proper diagnostics replaces speculation.

At this point in history, I would suggest the diagnostic steps to rule out TPS and EOT, save D for last, then focus on IACV and/or new ECM program, if outside USA.

14 months since I parted with my final bike (#17).
12,500 miles in 10 months.
6th nerve palsy of right eye is now history. Wife and kids signed me up for an intro helicopter lesson, but I have not yet set a time.

 

[peterbaron]

SportsterDoc, nice to hear about your health improving

 

[the Ferret]

Hard to believe it's been 14 months doc. Helicopter? I know a guy that became a helicopter pilot. He said keeping those things in the air is a real chore.

 

[SportsterDoc]

SportsterDoc, nice to hear about your health improving

Thanks, Peter.
I think I am in good health for approaching 73, but it seems I cannot work on something without cuts and bruises.
Son called Saturday about driver's window stuck down on 1989 F-250.
Did not take long to get it back into the channels and adjust track spacing, but there is a lot of sharp sheet metal under the door panel!

 

[peterbaron]

SportsterDoc, nice to hear about your health improving

Thanks, Peter.
I think I am in good health for approaching 73, but it seems I cannot work on something without cuts and bruises.
Son called Saturday about driver's window stuck down on 1989 F-250.
Did not take long to get it back into the channels and adjust track spacing, but there is a lot of sharp sheet metal under the door panel!

Thanks, Peter.
I think I am in good health for approaching 73, but it seems I cannot work on something without cuts and bruises.
Son called Saturday about driver's window stuck down on 1989 F-250.
Did not take long to get it back into the channels and adjust track spacing, but there is a lot of sharp sheet metal under the door panel!
Once you posses certain skills, the demand never forgets about you. Same here, just working part time for few more months, before full retirement.

 

[SportsterDoc]

Hard to believe it's been 14 months doc. Helicopter? I know a guy that became a helicopter pilot. He said keeping those things in the air is a real chore.

Yep, probably more risk than motorcycling, but I made wife and extended family a promise about motorcycling, but not about aviation...which they are supporting.

On a Robinson R22, a simple and common two seater, if the engine loses power, despite typical aviation dual ignition systems, the window to disengage the clutch, to avoid freefall, is only about 1.6 seconds, due to low enertia rotors.

Basic controls

 

[the Ferret]

Lol yea that doesnt look complicated at all. Kinda like early early motorcycles. Left handlebar controls the choke, right handle bar controls the throttle, left foot controls the clutch, right foot controls the rear brake, right hand controls the front brake, left hand controls the shift lever.....

 

[SportsterDoc]

Cyclic and collective, plus foot pedals are basics, but monitoring RPM clutch and manifold pressure are critical.

Controls are mainly about pitch...treat the engine as driving a class 8 tractor: Narrow RPM range.

I plan to participate in preflight inspection, especially of belts!

https://www.atsb.gov.au/media/4120236/ai-2009-038_final.pdf
Back to topic, idle issues can be diagnosed by following FSM proceedures...it is not a mystery.

 

[pdedse]

Hard to believe it's been 14 months doc. Helicopter? I know a guy that became a helicopter pilot. He said keeping those things in the air is a real chore.

Yep, probably more risk than motorcycling, but I made wife and extended family a promise about motorcycling, but not about aviation...which they are supporting.

On a Robinson R22, a simple and common two seater, if the engine loses power, despite typical aviation dual ignition systems, the window to disengage the clutch, to avoid freefall, is only about 1.6 seconds, due to low enertia rotors.

Basic controls

Are those instructions written on the back of the instructor's hand at the 1:48 mark?
:huh: