CB1100 Idle speed instability problem

[jedd_imp]

I can understand why the honda shop did what it did instead of what you're suggesting.

THey took the path of least resistance and got the job done with the least amount of risk. Go in once, and replace the whole kit and caboodle.

I would have done the same. It's good business. Especially when it's Honda who's footing the bill for the warranty claim.

[ericlo69_imp]

Cormanus, Popgunm, Kmoney and Jedd, Thanks for your replies.

HONDA Taiwan established the “HONDA Taiwan Motorcycle” in Apr’15; it means a lot of CB1100s were from parallel import trader.
The “dealer” in my previous posts means the parallel import trader, not “HONDA Taiwan dealer”, sorry for the confusing.
This case is in parallel import trader, and this bike is under trader’s warranty. Bike owner did not allow seeing technician’s actions during troubleshooting, we have no idea what has been replaced exactly.
A lot of owners are so care about this idle problem; it is not “cheap” troubleshooting, if the whole “Throttle Valve Assy.” is the root cause once bike is out of warranty. Some owners suggest that HONDA shall identify the root cause then recall the bikes!

As I mentioned that several CB1100 got idle speed unstable problem, and these bikes are pretty new (less than few thousands mileage); and I assumed the failure part is idle motor; how come this motor died so quickly? Defect parts?
Another guess, is it possible that the root cause is the “carbon deposit” on the motor?

[Cormanus]

Erico, is it only the 2015 models that are having problems?

[ericlo69_imp]

Original model is introduced in Y2010, and revised model is introduced in Y2014; the major differential is the gearbox (Y2010:5 speeds; Y2014: 6 speeds).
So far we found that only revised model (14'~) has idle speed problems.

By the way, some other owners said Idle speed would drop to 500rpm, ONLY in summer time.

Erico, is it only the 2015 models that are having problems?

[Lord Popgun]

Only in Summer time? I wonder if the temp sensor is out of spec.

[ericlo69_imp]

Another clue:
in Taiwan CB1100 (after 2014) has two major models; one has two exhaust pipes (model name: CB1100EX) and another one has only one exhaust pipe (model name: CB1100).
Mostly idle speed problem happened in CB1100EX model.
One owner doubt:
CB1100 & CB1100EX have different computer program, and CB1100 has one oxygen sensor only, CB1100EX has two oxygen sensors.
Is it possible that CB1100EX’s computer program could not handle the signals of two sensors sometimes?!

[Tom JAN_imp]

http://cb1100forum.com/forum/showthread....light=idle

The same problem

[ericlo69_imp]

Update: replaced the whole “Throttle Valve Assy.” already; seems problem was solved.

[the Ferret]

Glad it got sorted out.

[uscgmac_imp]

I have a friend with a 2014 standard and hes having similar problems. His bike is ideling at 1500 rpms all the time. Even after riding for a while. He has about 4500 miles on the bike. He is still under warranty and bringing it back to the dealer.